Overview

José Antonio Izazola-Licea

Introduction

The appearance of the Acquired Immune Deficiency Syndrome (AIDS) was described for the first time in 1981 in the United States of America; unlike other recent diseases (such as ebola), it has had a rapid dissemination and a great social impact.

AIDS is the final phase of the Human Immunedeficiency Virus (HIV), which may take from 5 to 20 years to manifest itself once individuals have been infected.(1) Starting from the appearance of immunedeficiency and its manifestation in "opportunistic" infections or in neoplasias, individuals can survive up to two years even without antiretroviral or prophylactic therapy. Survival can be increased in quantity and in quality by means of currently available therapies.(2)

The AIDS pandemic is composed of diverse, more localized epidemics, which have a dynamics of their own and which, by bearing similarities according to regions, can be characterized as epidemiological patterns. Initially, it was thought that these patterns were explained essentially by differences in sexual behavior and by the shared-use of needles and syringes during the application of intravenous drugs. However, now other hypotheses are proposed for explaining such differences; for example, the differential transmission according to different HIV subtypes.(3) Differences have also been noted in the composition of the epidemics according to the early adoption of efficacious preventive measures, both in HIV sexual and blood transmission.

AIDS already has a place in history, not only because of its great negative impact on health but also because of setbacks in gains on infant survival in some countries. Indeed, part of the complexity of AIDS is that it involves sexual behavior as one of the main routes of HIV transmission, the latter being an area considered to be intimate and subject to moral judgment by some. The appearance of AIDS has brought to light some processes which socially influence the history of societies; for example, the stigmatization of patients with terminal, chronic or disfiguring diseases, such as bubonic plague, leprosy, syphilis, and now AIDS. The fear of being affected causes some people to deny the problem and to attribute it as a problem of others, frequently resulting in decisions being made in non-ideal conditions.

Projection exercises of the AIDS pandemic show a trend of accelerated growth in marginal populations. In this way, what groups were the ones initially affected is merely incidental: this epidemic, once mature, invariably spreads more rapidly among vulnerable populations which have been traditionally economically or socially marginal;(4) and it turns into an endemic disease of heterosexual transmission, accelerated only because of women’s lack of power in their relationship of equality to men and by the discrimination toward other groups such as indigenous people, homosexuals, widows, orphans, etcetera.

In 1996, scientific advances made it possible to state, for the first time, the hypothesis of control of the HIV infection by efficacious antiretroviral treatment; however, this will be accessible only to a minority of persons, essentially in industrialized countries, whereas it will be virtually unattainable for the majority of the infected individuals in developing countries, where currently 9 out of every 10 HIV infections occur. This situation is little different to other efficacious alternatives of prevention of perinatal transmission by the use of antiretroviral treatment at the time of birth. The control of blood banks has demonstrated its usefulness when one has had sufficient resources for its implementation; however, its high cost and economic impact on health systems is clear. The probable future emergence of a vaccine could also bring to light the inequality among individuals and countries; once again, only those with sufficient economic means will be able to rely on this preventive tool.

The prevention of HIV sexual transmission is based on a change in behavior; it is now clear that community participation is indispensable for the sustained change needed to alter the AIDS epidemic significantly, a process linked to the democratic development of societies.

The continuing growth of the pandemic, in addition to the change in the composition of the affected, now leads to some people wanting to deal with AIDS as an endemic problem, as acceptable as malaria or malnutrition, as long as it is considered of other people’s bussiness. Unless one implements an intense and well-directed strategy for the prevention and the control of the HIV infection and one furnishes adequate comprehensive medical care to the infected, the social and economic impact of AIDS on health-care systems, and in general on societies, will be increasingly greater. Indeed, health authorities should propose an effective combat against AIDS, both preventive and curative, as part of the right to health protection; however, the most efficient form should not necessarily envisage the direct payment of governments of these activities.

In the light of the advance of scientific and technological discoveries about HIV and AIDS, of its pathogenesis and effective forms of fighting against it, the most important question is no longer about the feasibility of such discoveries, but about how to make them accessible to populations who most need them. The question has ceased to remain solely in the scientific and technological realm; it is now an economic question as long as there are scarce resources available, and it is also a political question in attempting to decide who will pay for the treatment of the poor or the uninsured.

The costs of HIV/AIDS, by the appropriation of resources in developing countries, characterized by a scarcity of capital, are a matter of great importance in the debate on economic development of Latin American and Caribbean countries. The scarcity of economic resources, in turn, makes it imperative to define priorities in governmental action. It is clear that the prevention of HIV infection must be sufficiently financed, probably with public funds, since it turns out to be a cost-effective intervention. Therapeutic interventions, even though they are not considered to be cost-efficient with the available information, should be carried out according to the social security arrangements existing in each country; the uninsured population, however, is the one that remains unprotected under these schemes.

The changes in the efficacy of antiretroviral or prophylactic treatments concerning AIDS have been dramatic and frequent. Consequently, cost-efficiency or cost-effective studies of the treatment become outdated. The higher effectiveness of multiple antiretroviral treatments, which include protease inhibitors, has produced an increase in the costs of standard treatment for AIDS, but it has also modified radically the results obtained with new therapeutic schemes. For this reason, one should again evaluate the estimates of the cost-effectiveness ratio, in order to be able to use adequately this information in the process of giving priority to publicly funded actions, in a context of scarce resources and multiple needs.

Virological and Clinical Aspects of HIV

Background Information on the Virus

When the first AIDS cases in Latin America were diagnosed, little was known about the disease. The causal agent had still not been identified, although outbreaks of Kaposi Sarcoma and Pneumocystis carinii pneumonia in homosexual and bisexual men with multiple partners were already being described,(5,6) and cases among heterosexual couples, infants, hemophiliacs, and receptors of multiple blood transfusions were being reported. These studies supported the hypotheses of HIV sexual, blood and perinatal transmission,(7-9) as the only efficient routes of transmission which, so far, have been proved to exist.

The HIV is a retrovirus of the Lentiviridae family, which were initially described in feline and bovine pathologies. The first retrovirus described in humans was the HTLV-I, in a form associated to a type of T-cell leukemia in adults. In this way, the advent of technology to identify, isolate and characterize the retrovirus of the 1960s permitted the speedy description of the causal agent of AIDS, as well as the relatively early development of methods of diagnosis and detection of HIV infection.

One of the characteristics of HIV, which has implied greater difficulty for the discovery of vaccines and possibly the development of viral resistance, is the fact that the HIV has a large genetic variability and a high mutability, which is very likely to have repercussions on the future of the epidemic and on the design of strategies aimed at its control.

To date, two types of HIV have been described, type 1 and 2. HIV-1 has, at least, 10 different viral variants or subtypes at the world level which are designated with letters, from A to I, and group O. These subtypes presented a regional pattern at the start of the epidemic, and now they have disseminated. Thus, in Brazil and Argentina the HIV-1 subtypes B, F and C have been described; in Mexico, the B, F and D subtypes; and in Cuba basically the B subtype. Apparently HIV transmission is differential by subtype, with the predominance of the E and C subtypes for heterosexual transmission and the B subtype for homosexual transmission and through intravenous drug use. HIV-2 has, apparently, a more benign evolution than that of type 1 and possibly prevents the latter’s infection by a crossed reaction. In order to face better the AIDS epidemic, it will be necessary to know the subtypes and the characteristics of the viral variants circulating in our populations. Although to date the available techniques for the diagnosis of HIV infection (e.g., enzyme immunoassays (ELISA) and Western Blot techniques) are considered to be high-precision diagnostic tools, it is important to establish if viral variation affects the performance of these studies.(10)

Vaccines (I)

In spite of all the knowledge acquired over the last few years about HIV, an available effective vaccine does not yet exist. This fact is related with the difficulties inherent to HIV, which had not been encountered previously in the development of vaccines against other viral agents.

According to the diversity found in HIV, the vaccines must be directed at the specific subtypes circulating in the populations one intends to protect, and most probably they must be polyvalent against various HIV subtypes. Due to the absence of adequate animal models and to the results of phase I and phase II clinical trials in humans, one should proceed with phase III clinical trials to test the vaccines’ effectiveness.

However, multiple problems remain to be solved before having a vaccine available for its non-experimental use. A period of from 5 to 10 years must elapse in order to evaluate if the vaccine effectively has a protective effect, and that the disease has not been induced with the vaccine. Such evaluation, in turn, must have a statistical design envisaging the adoption of preventive measures, which by reason of ethics should be promoted in exposed populations who are under a research protocol. To exemplify this situation, a vaccine should be evaluated where there are high rates of incidence in order to be able to detect significant differences between the vaccinated and the non-vaccinated population; ethically, one must promote the adoption of safe sex or condom use in these exposed populations, which reduces the difference in the incidence of infection among the vaccinated and the non-vaccinated population, thereby complicating the process of evaluation of the vaccines’ effectiveness. Additionally, one must take into consideration the circulating subtypes and the specificity of such vaccines.

Studies are already under way that take into account the route of HIV infection. Thus, even though the importance of mucosal immunity has not been established, independently of the type of vaccine used, the infection should probably be prevented through these routes. Recent reports of new DNA vaccines, currently under evaluation, induce an adequate mucosal response mediated through IgA.

In addition to the complexity in the development of vaccines, there continues to exist a vacuum on immunological parameters which correlate with protection. It is necessary, then, to have new methodologies of quantitative evaluation of the cellular immunological function in order to asses the effectiveness of the vaccines.

At the start of the epidemic, when HIV was described as the causal agent of AIDS, false expectations were raised concerning the early discovery of a vaccine, leading, erroneously, to forecasting the end of the epidemic. Population groups, in whom a significant change of behavior had been achieved in the adoption of safe sex, soon forgot such practices, thereby giving way to a new epidemic peak, for example, among homosexual and bisexual men in the United States.(11)

Furthermore, it has been recognized that the mere availability of a vaccine would not be capable of containing the epidemic. Even if a vaccine were currently available for field application, practical problems would be encountered that would prevent its accessibility and utilization with sufficient coverage to limit the problem of HIV infection: The costs, the effectiveness and the acceptance of the vaccine could seriously limit its utilization as occurs with other vaccines available since a number of years ago, such as vaccines against measles, tetanus, and hepatitis B. The solution to the growth of HIV/AIDS by means of a vaccine will be more viable in countries having financial resources to guarantee an adequate coverage.

Treatment (II)

During 1995 and 1996 important findings have been described in four main clinical areas: HIV primary infection; virological markers to predict disease progression and monitoring of therapeutic efficacy; treatment and prophylactics of opportunistic infections; and antiviral therapy.(12)

The management and pathogenesis of HIV primary infection have been the subject of greater attention, in view of the evidence, increasingly greater, that early antiretroviral treatment has a beneficial effect on the subsequent clinical course of the infection; thus, one could recommend the detection of individuals in the primary phase of HIV infection, even before the occurrence of some immunological harm. However, this perspective is still being debated owing to, among other causes, the collateral effects of the antiretrovirals, the development of viral resistance, and the high cost involved in maintaining antiretroviral therapy over a prolonged period of time.

In the last few years, methods have been developed to measure this viral replication with enormous precision. These methods, which include the quantitative detection of viral nucleic acids in plasma, have been recognized as useful predictors of the long-term evolution of the HIV-infected patient. The measurement of the viral load permits one to discriminate very precisely patients whose velocity of progression will be different in the long term; this measurement has also been used to evaluate the response to antiviral treatment. Several studies have demonstrated that the changes in viral load in response to treatment is associated to a change in the prognosis, and therefore the viral load can be used as a marker of the efficacy of antiviral treatment. Current recommendations for managing an HIV-infected patient include the use of potent antiretrovirals and monitoring its efficacy by means of viral load measurements.

As for opportunistic infections, progress has been made in the evaluation of new prophylactic schemes against different opportunistic infections, putting special emphasis on the analysis of cost-efficacy. Trends in the prophylaxis of opportunistic infections suggest the use of useful medication for various infections, such as for example trimetropim-sulfametoxazole for Pneumocystis carinii pneumonia (PCP) and also to prevent toxoplasmosis. Furthermore, reports have been received of outbreaks of multirresistant M. tuberculosis in hospitals in different parts of the world, so that the use of multiple treatment against tuberculosis is recommended, the combination of which is currently being evaluated in seropositive patients. It is worth noting that attempts are being made to simplify the administration of medication, while the use of multiple prophylactic treatments with complicated administration schemes only serve to diminish compliance to the therapeutic schemes.

Concerning antiviral treatment against HIV, currently eight drugs have been approved in the United States for use in HIV-infected patients. These are nucleoside analogs (AZT, DDI, DDC, D4T and 3TC) and protease inhibitors (ritonavir, indinavir and saquinavir). Other drugs are in advanced stages of evaluation such as non-nucleoside reverse transcriptase inhibitors, nevirapine, delarvina, and other protease inhibitors.

The use of a combination of antiretrovirals is now the recommended practice, based on the results on virologic markers that have been correlated to beneficial clinical effects; therefore, the use of monotherapy should be discouraged. The principles of current antiviral therapy should be based on achieving a maximum virological suppression, for the longest period of time possible and starting as early as possible. In the recommendations of the International AIDS Society, issued in July 1996, emphasis was put on the use of the viral load as a measure of effectiveness of antiviral medication as well as for deciding on when to start its administration.

Several schemes in combination have been evaluated. Some of the most promising are AZT / 3TC / indinavir or ritonavir; saquinavir / ritonavir; DDI / D4T; AZT / DDI / nevirapine. The decision of using protease inhibitors as the initial treatment is controversial and is not accepted in all cases. The differences between protease inhibitors as to antiviral activity, development of resistance, toxicity and interactions with other drugs will be what determines the initial selection of one or another. So far, there is no consensus over which is the recommended protease inhibitor for initial use.

Given the advances in the treatment of HIV infection, AIDS is on the way to becoming a controllable chronic disease, by preventing the development of opportunistic infections and even that of immunedeficiency. However, the degree of complexity in the management of patients has increased substantially, so that health-care models need to be planned taking into account the patients’ prospects and the greater efficacy in the treatment. The high degree of complexity suggests that the provision of medical care to an HIV-infected patient should not be divided into primary, secondary and tertiary levels of medical care.(13) Specialized medical care should be provided from the early stages, which is when more benefits can be obtained for the patient. Moreover, it should be considered that to the extent that the immediate threat to life disappears from view, the compliance to the treatment and the adequate use of medication may be reduced, as has been observed in other potentially terminal diseases (for example, diabetes mellitus).

It should be noted, by way of conclusion about the advances in treatment, that the use of combined therapies which include protease inhibitors, in spite of having afforded very promising results over a 48-week follow-up time period, does not constitute the "cure" against HIV infection.

The combined use of antiretroviral drugs, of prophylactic medication and laboratory tests for monitoring the advance of immunedeficiency (CD4+ cell count and the quantity of viral load) represents a great economic cost in the treatment of patients, which is out of reach for several health-care systems. For this reason, and owing to the ethical relevance of providing technologically available treatment, there is a need to search for strategies to provide the greatest population coverage in the most cost-efficient way possible.

The fact that this technology is available should not be an excuse for neglecting preventive activities; on the contrary, the obligation to provide adequate treatment with high economic cost ought to be the best incentive to prevent new HIV infections.

To foster the increase in the coverage of anti-retroviral treatment, governments may undertake diverse actions which do not necessarily imply large expenditures. By way of example, central governments may, possibly through their health ministries or charity agencies, effect massive purchases of the medication, to guarantee the lowest prices. These medications could then be sold at cost and the original expense would be recovered; thus, patients and other agencies would have access to lower-cost medications.

Epidemiology of HIV/AIDS

The main aim of epidemiology is to produce information for the action; it is used to analyze the frequency and distribution of diseases and to identify characteristics in the acquisition of the disease which can be modified (risk factors). The adequate use of epidemiological information permits one to describe which groups are more likely to acquire HIV as the target population for interventions, or else it permits one to identify practices as the objectives for behavior change which must be modified to significantly alter the course of the epidemic. So far, it is recognized that biological, social and behavioral factors have determined the course of the epidemic. As a major cause of mortality and morbidity, AIDS dramatically increases the burden on the health services and diverts scarce economic resources for the treatment of patients, when such resources could be used for preventive programs. All efforts to characterize the HIV epidemic are directed at achieving the objective of controlling this disease, reducing its social costs, and, additionally, controlling its costs.(14)

Most HIV infections and AIDS cases are occurring in developing countries in Africa, Asia, and Latin America and the Caribbean. Recently, the epidemic has gained momentum in the newly independent states of the former Soviet Union.(15)

Using the figures estimated by the Joint United Nations Program on HIV/AIDS (UNAIDS),(16) it is calculated that, since the beginning of the pandemic in the 1970s up to mid-1996, there would have been 7.7 million people in the world who developed AIDS; 5.8 million who died from AIDS; and 27.9 million people who became infected with HIV.

In 1995 AIDS is estimated to have caused 1.3 million deaths: of which 300,000 were children, 400,000 were women, and 600,000 were men. Furthermore, by mid-1996, 21.8 million people are estimated to be living with HIV infection, still not diagnosed as AIDS. During 1996 there will be 3.1 million people newly infected with HIV¾ that is, 8,500 new infections per day, the majority in persons aged 15-to-24, and 1,000 among children. The increase in the number of reported cases from mid-1995 to mid-1996 was 19 percent.

The prevalence of HIV infection is unequally distributed in the world: the highest estimated prevalence among adults is in Sub-Saharan Africa (5.1%), compared to Eastern Asia and the Pacific which have an estimated prevalence of 0.01%, Latin America 0.5%, and the Caribbean 1.4% (see Figure 1 and 2).

Figure 1 Estimated distribution, as of mind 1996, of adults and children infected with HIV since the late 1970s (global total: 27.9 million).
Source: UNAIDS/COS/SG/96017-1bw 30 June 1996.

 

Figure 2 Adult HIV prevalence rates (%) by subcontinent, mid 1996.
Source: UNAIDS/COS/SG/96018-2bw 20 June 1996.

 

Epidemiology of HIV/AIDS in the United States, Canada and Western Europe

In these regions, more than 1.2 million adults are living with HIV/AIDS (including more than 750,000 in the United States alone), which accounts for 6% of the total number of cases in the world. At the beginning, the epidemic in these countries affected homosexual and bisexual men. At present, the epidemic involves largely injecting drug users and their sexual partners, who may or may not be drug users. Up to 75% of infections occur in injecting drug users or in their partners.

Ever since the epidemic began, in the late 1970s, AIDS has come to rank as the number-one cause of death in adults aged 45 or younger in many US and Western European cities. In Western Europe currently around 450,000 people are infected with HIV or have AIDS. There are indications that the HIV prevalence has stabilized in countries such as Belgium, Germany, the Netherlands, Sweden, and the United Kingdom. Switzerland has reported a reduction in new AIDS cases, but the situation is less encouraging in countries such as Spain, Portugal, and Italy.

Epidemiology of HIV/AIDS in Eastern Europe and Central Asia

In Eastern Europe and Central Asia, 29,000 adults are estimated to be living with HIV/AIDS. Although this prevalence is still low, it is likely to increase since the region has many factors conducive to a rapid dissemination of HIV: economic crisis, rising unemployment, deteriorating health systems, ethnic and religious conflicts, displacement of civil populations, as well as migration in search of new economic opportunities. The rate of infection is 15 per 100,000. Some countries have evidenced a rapid spread of HIV infection, particularly Ukraine and Poland.

Epidemiology of HIV/AIDS in Southern and Southeast Asia

The virus is spreading rapidly and silently in most of Asia, the world’s most populated region, especially in the southeastern part of the continent. Thus, the total number of infected persons increased from 500,000 in 1991 to 3.5 million between 1991 and 1994, and to date a total of 4.7 million adults are estimated to be living with HIV. The World Health Organization (WHO) estimates that, by the late 1990s, the annual number of new cases in the region will surpass that occurring in Africa, reaching an accumulated total of 55 million people infected with HIV by the year 2000; the WHO estimates, moreover, that by the end of the century a total of 1.4 million people will have developed AIDS in Asia.

HIV was initially identified in Asia among injecting drug users and in men with homosexual practices. At present, while injecting drug abuse still plays an important role in the spread of HIV, heterosexual transmission is the major cause of infection in the region.

India is the country with the largest number of infected adults with an estimated 3 million; however, its prevalence in adults has not reached 1 %. Elsewhere, Thailand is the country with highest prevalence in the area, with slightly more than 2% among adults.

Epidemiology of HIV/AIDS in Africa

The African countries in the central, eastern and western areas to the south of the Sahara, with less than 10% of the world’s population, account for more than 70% of persons infected with HIV and more than two-thirds of AIDS cases worldwide. Ever since the epidemic began in this region, in the mid-1970s, around 13.3 million adults and over one million children are estimated to have contracted HIV, and close to 3 million people to have died as a consequence of AIDS. Most of the infections have been acquired in heterosexual relations, with the number of infected women higher than that of infected men. Approximately 8 million African women in childbearing age are infected with HIV and one million children have been infected before or during the time of birth or through breast feeding.

There exists, however, a wide variability in the AIDS-related incidence in Sub-Saharan Africa. The prevalence of HIV ranges from 0.1% in the Comoros to 18% in Botswana.

Life expectancy at birth in the fifteen-year period of 1990-1995 decreased from 52.8 to 49.6 years in the 15 countries which had a prevalence of over 1% in the population aged 15-49.

Epidemiology of HIV/AIDS in Latin America and the Caribbean

Latin America and the Caribbean have a relatively lower number of HIV infections than Asia or Africa. However, and despite that Latin America and the Caribbean represent 8.4% of the total world population, these regions already contain 11.5% of all persons infected with HIV in the world.

The initial spread of the HIV infection began in Latin America in the mid-1970s and the early 1980s. Homosexual and bisexual transmission are estimated to continue to be important in this region, but heterosexual transmission is turning into the principal route of transmission. Sharing contaminated needles and syringes among drug users is also a common route of HIV transmission in many cities, especially in the South Cone of South America. Between 1988 and 1992, the rates of infection in Latin America and the Caribbean nearly tripled and towards the end of 1994 the region had more than 2 million HIV infections and around 405,000 AIDS cases.

As in other regions of the world, the AIDS epidemic in Latin America and the Caribbean is becoming a high-priority public-health problem. The World Health Organization and UNAIDS estimate that by 1996 there are a total of 1.6 million infected people living in Latin America and 300,000 in the Caribbean. As of June 1996, a total of 176,930 AIDS cases were reported in Latin America and the Caribbean. Nine countries (Brazil, Mexico, Colombia, Venezuela, Honduras, Dominican Republic, Peru, and El Salvador) account for 80% of the cases. Mexico and Brazil contribute, altogether with more than 7 out of every 10 infections in Latin America, 18% of them in women. Overall, this region contributes 6% of the total number of cases worldwide.

In the Caribbean, there are more than 250,000 infections among adults; however, this represents 1% of the world total, although the prevalence among adults (1.4%) is surpassed only by that found in Sub-Saharan Africa. The most affected countries are Haiti and Barbados with a prevalence among adults of around 4%; the Dominican Republic and Haiti, taken together, account for 85% of the total number of cases in the Caribbean. Cuba is the country with the lowest prevalence (0.002%).

The AIDS epidemic in Latin America has caused around 80,000 deaths and is on the way to ranking as the major cause of death among men between 25 and 44 years of age. Because AIDS affects this important segment of the productive labor force, its impact on productivity might be substantial. Determining the size of the epidemic is critical because of its demographic, economic, and public health implications.

Epidemiological Patterns in Latin America and the Caribbean

As for the distribution of AIDS cases by mode of transmission, these may be classified into the following three dominant trends:(17)

1) One characterized by the predominance of transmission by male homosexual contact, followed by sexual transmission and, finally, other categories (blood transfusions, injecting drug users, etc.). This type of transmission is typical of the Andean region: Bolivia, Colombia, Ecuador, Peru, and Venezuela (see Figure 3), and, to a lesser extent, Mexico (Figure 4).

Figure 3 Annual incidence of AIDS cases, by certain risk factors, 1983/95. Andean Area.
Source: Pan-American Health Organization HIV/AIDS in The Anericas, January 10 update.

 

Figure 4 Annual incidence of AIDS cases, by certain risk factors, 1983-1994/95. Mexico
Source: Pan -American Health Organization HIV /AIDS in the The Americas, January 10 update

2) A variant of the above-mentioned pattern is that of the South Cone (Argentina, Chile, Paraguay, and Uruguay), where transmission is predominantly among men who engage in homosexual practices, followed by a rapid increase in intravenous drug users and by heterosexual transmission (Figure 5). Brazil also has a similar behavior (Figure 6).

Figure 5 Annual incidence of AIDS cases, by certain risk factors, 1982-1994/95. Southern Cone.
Source: Pan-American Health Organization HIV/AIDS in The Americas, January 10 update

Figure 6 Annual incidence of AIDS cases, by certain risk factors, 1980-1994/95. Brazil.
Source: Pan-American Health Organization HIV/AIDS in The Americas, January 10 update.

3) Finally, in the Caribbean the main characteristic is predominantly related to heterosexual transmission, in such a way that it has been compared to patterns observed in the African continent (Figure 7). In Central America (Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama), particularly from 1990 onward, some authors have described a "heterosexualization" of the epidemic, including a minority component of male homosexual transmission (Figure 8). A dramatic example of the high growth in cases related to heterosexual transmission has been observed in Honduras, a country in which a total of 4,973 cases and 955 deaths had been reported by the end of 1995.

Figure 7 Annual incidence of AIDS cases, by certain risk factors, 1981-1994/1995. The Caribbean
Source: Pan-American Health Organization HIV/AIDS in The Americas, January 10 update

Figure 8 Annual incidence of AIDS cases, by certain risk factors, 1983-1994/95. Central America
Source: Pan-American Health Organization HIV/AIDS in The Americas, January 10 update

Disability Adjusted Life Years lost due to HIV/AIDS and other STDs

A methodological development exists that quantifies the burden of diseases by calculating the Disability Adjusted Life Years (DALYs) lost including disability and premature mortality.

This indicator contains a discount of the future impact due to current infections, and shows that in Latin America and the Caribbean the DALYs due to HIV contributed with 10% of the transmissible diseases, maternal and perinatal, and 25% of the infectious and parasitic diseases in 1990. HIV/AIDS contributed the double of what was caused by maternal mortality and the equivalent of 80% of what was contributed by acute respiratory infections in the same year (Table 1).(18) Even though more recent information is not available, the DALYs lost due to HIV/AIDS are expected to increase to the extent that AIDS cases in the region have increased. i.e., annual cases increased 10-fold in the period from 1990 to 1995 (in 1990, 15,651 AIDS cases were reported, and 155,169 cases were reported in 1995).

 

Table 1. Disability-adjusted life years (DALYs, in thousands): Latin America and the Caribbean

 

	Both sexes all ages	Males	Females
ALL CAUSES	102,892	57,218	45,674
Communicable, maternal & perinatal	43,415	22,649	20,766
Infectious & parasitic diseases	25,851	13,783	12,067
STDs excluding HIV	2,403	244	2,159
HIV infection	4,435	3,414	1,021
Noncommunicable	44,030	22,847	21,183

Because of the natural history of the disease¾ which indicates that up to 20 years may elapse between the infection with HIV and the clinical diagnosis of AIDS,(7) even without prophylaxis and antiretroviral therapy¾ the presence of early symptoms not diagnostic of AIDS, the psychological burden of knowing to be seropositive, and to the average four-year survival period once diagnosed with AIDS, the burden of the disease corresponding to HIV/AIDS should be measured not only as mortality, but also as morbidity and disability.

Life years lost due to premature mortality caused by HIV/AIDS

By the end of 1995, there were a total of 388,633 deaths caused by AIDS in the American continent; of these, 311,000 occurred in the United States, 36,024 in Brazil, and 14,167 in Mexico.(19)

In Mexico, the mortality caused by AIDS has gained ground within the major causes of death among young men: in 1988 AIDS ranked eleventh as the cause of death among men aged 25-34; in 1992 it ranked fourth;(20) and currently it ranks third (Figure 9).(21) Several studies have noted, moreover, that such data can still be corrected. By way of example, in the United States the mortality recorded directly as AIDS needs a correction factor. An study conducted in San Francisco, California, indicates that 9% of the deaths due to AIDS were not directly recorded as such on the death certificate;(22) a United Sates national study suggests that a correction of 26% needs to be added to the recorded number of AIDS deaths occurring among men in the age group 25-44.(23)

Figure 9 Rate of mortality (per 100 000 inhabitants) of the main causes of death in men , ages 25-34

In Mexico, preliminary results of a study(3) indicate that the mortality rate in young men (age 25-44) should increase by 30% owing to this process of inadequate certification. For example, for 1994, of the cases not certified as HIV/AIDS which are ascribable to this cause, 37% were classified as meningitis caused by enterovirus; 7% as tuberculosis; 12% as pneumonia; 5% as virosis of the central nervous system; 4% as anemia; 13% as missclassified bacterial infections, etc. The major conclusion in using this correction is that mortality due to AIDS contributes 12% of the total mortality in this group in Mexico. This process of miss-classification of the cause of death may occur because physicians involved in treating such patients do not record HIV/AIDS as the cause of death.(24) It is to be expected that a similar process is occurring in the rest of the region.

Prevention of HIV(III)

The subtypes recognized to be circulating in Latin America and the Caribbean and the biological variability of HIV have the potential to produce new sub-epidemics in the region. For example, if the hypothesis of a subtype with a greater efficiency for heterosexual transmission is proved correct, and considering that this subtype has not yet circulated in the American continent, and considering that about 10 million adolescents annually initiate sexual activity, clearly there is a potential for a latent heterosexual epidemic.

While the new viral characterization will make it possible to monitor the geographical distribution of sub-epidemics, it also has important implications for the development of a vaccine. Any vaccine, to be efficient, must induce immunity that recognizes the envelopes of the different subtypes, as has been mentioned previously in this chapter. However, in spite of the identification of these subtypes, in terms of prevention of HIV sexual transmission, one thing should remain very clear: protected intercourse continues to be the best way to prevent the spread of the HIV regardless of its subtype.

Sustained efforts to maintain continuing campaigns for protected sexual intercourse and condom use are necessary. Although it is true that governments are responsible for the provision of preventive and health-care services for the population, community involvement and participation are essential for the success of preventive interventions to control the AIDS epidemic.

Concerning the prevention of HIV/AIDS infection, it is known that information, education and communication models designed to promote awareness among the public at large of the existence and the mechanisms of HIV transmission have not led to changing HIV-risk behaviors. To state it once again, there is no linear and direct relationship between knowledge, attitudes, and practices. Information does not suffice to prevent AIDS. Preventive interventions should not only change individual behaviors in an isolated manner from other underlying conditions; HIV/AIDS-risk behaviors in vulnerable populations are entrenched in broader contexts which determine them.(25)

The determination of preventive programs is based on the identification of factors that are associated with an increased risk of acquiring HIV infection. When these factors are susceptible to being changed, then one can plan and assess programs to prevent infection. In the case of HIV infection, having unprotected (without condom) sexual intercourse is still the most important risk factor for acquiring the infection. Up to now behavioral factors and social networks had been considered to be much more important elements in spreading the epidemic than the biological factors of the virus. The success of community programs is based on a design sensitive-to-the-needs and customs of the targeted communities, as well as on the participation of persons who are part of the same community. The presence of sexually transmited infections is associated to a higher risk of HIV transmission; for this reason, one should stress their treatment and widely prevent them by the use of condoms. Two strategies for providing information on HIV and promoting the consistent use of condoms include interventions aimed at mass media and those directed to specific groups, i.e., face-to-face interventions..

For other routes of transmission such as parenteral, the self-exclusion of blood donors at risk of being infected, the prohibition of blood commerce and the universal screening of blood donations with the elimination of infected products have been successful for controlling the transmission by blood transfusion, to the point in which blood transmission cases have been significantly reduced. (Figure 10)

Figure 10 Prevention strategies in Mexico

Cases of HIV infection related to injecting drug use in Latin America- located in urban areas such as cities on Mexico’s northern border, Rio de Janeiro, Brazil, and Buenos Aires, Argentina- require intense intervention.

One of the most promising areas of prevention is in perinatal transmission. At present, the standard care for pregnant HIV-infected women includes zidovudine administered to the mother shortly before, during and to the baby after the partum, since it is able to reduce transmission in two thirds of the cases, i.e., from an estimated 24% to an estimated 8%.

Social Vulnerability, Human Rights and AIDS

During the past decade important changes have taken place in the research on the social impact of HIV/AIDS and on a critical reflection about the epidemic, both from the point of view of political theory and of practical experience. Such is the case of studies that attempt to understand and attack the social, economic and political determinants of the epidemic, as well as innovative designs of preventive interventions based on the understanding of AIDS as a social problem that must be dealt with from a community level.

These changes are based on several issues. Although the universal biological susceptibility to HIV infection is true, the epidemiology of the infection shows that certain groups are more vulnerable because of their social, economic and cultural conditions, such as women, youngsters, the poor both in developing countries and industrialized societies, and groups that have been stigmatized for their sexual practices such as men who have sex with men. Hence the reason why the concept of "social vulnerability" regarding HIV infection has gained great importance and why the need to direct research and prevention efforts toward broader areas than individual behavior change is being discussed.

The major challenges that AIDS implies in our societies lie not only in the prevention of blood, sexual and perinatal HIV transmission, but also include reducing the impact of HIV infection on individuals, on groups, and on societies. Other challenges include the provision of health care for AIDS patients, the stigmatization of the affected and their families, and the complacency in regard to a disease which, according to some, is already an "acceptable" cost of living in modern times.

Because fighting against HIV/AIDS requires and will require sizable economic resources, the inequity among countries, societies and individuals adds a degree of difficulty, given our Latin American reality.

In fact, AIDS has uncovered the greatest weaknesses of our societies, by making us reflect on the identity and the behavior of the affected persons and, necessarily, showing us the existing diversity from way back. We have had to face in an explicit manner the need to respect individuals who do not think or do the same as "us" and who, however, share our same rights. The rich and the poor, housewives and homosexual men, prostitutes, drug users and adolescents will have those same rights. The same rights as citizens and the same human rights.

Tolerance existing before the onset of AIDS, for example in sexuality, was transformed; thus, some became more intolerant and others are now respectful of the human diversity.

Despite that in some countries the initially affected groups were those who enjoyed better economic conditions, at the world level it has been observed that the HIV/AIDS pandemic affects inexorably, and increasingly, individuals with greater vulnerability. This vulnerability is due to biological conditions, economic situations, sexual practices, or a combination of these and other situations. In other words, on account of being a woman, of being poor, of being homosexual, of being a migrant, of being a prostitute, of being a drug user, or of being a housewife. It is clear that an effective response for fighting against this disease demands the mobilization of society, both through governments and civil society itself.

The affectation of women by the HIV/AIDS epidemic has been unequal in the world; while in Sub-Saharan Africa and the Caribbean the number of affected women is equal to or slightly higher than the number of affected men, in Latin America women account for only 18% of the cases. Worldwide, by mid-1996, 12.2 million adult men and 8.8 million adult women are estimated to be living with HIV.

However, the conditions of women¾ particularly owing to their state of inequality in decision-making and in social participation, as well as because of their biological characteristics¾ cause them to become a vulnerable population for acquiring HIV infection, essentially due to actions taken by their male partners, often in spite of being aware of the risks involved for women and their children.

In this sense, it is urgent to undertake research on women, from a gender perspective, about the lack of perception of risk for HIV/AIDS, of the obstacles for negotiating safer sexual practices, and about the role of different social institutions as favoring or hindering the campaigns aimed at fighting against AIDS. Among the most urgent proposals to stem the epidemic, primarily among women in the region, are the following:(26)

Include specific educational messages for women.

Achieve the production, distribution and wide accessibility of the female condom and other methods of protection controlled by women.

Broaden the coverage and the accessibility of comprehensive childbearing health services, which should include AIDS prevention actions and the detection and treatment of their sexually transmitted diseases.

Economic Impact of HIV/AIDS

Impact of HIV/AIDS on the Economy(IV)

When AIDS first appeared at the beginning of the 1980s, it was primarily considered a public-health problem. However, because HIV infection was associated to determined sexual practices, in some countries there was the dilemma of regarding AIDS as an ethical or moral question or as a public-health question. Clearly, the discussion of that dilemma distracted from giving attention to the central points of the problem, and currently, in addition to being a public-health problem, AIDS has become a concern for economic development.

In fact, the evolution of HIV/AIDS is adversely affecting development. In the long term, productivity (production per worker) is nearly all that matters for economic development. The capacity of a country to improve its standard of living over time depends almost completely on its ability to raise its production per worker. To be fair, and as a purely arithmetic question, at least in a closed economy, there are three ways of increasing a country’s per capita consumption: a) increasing productivity, so each worker produces more; b) putting a larger portion of the population to work; and c) putting a smaller fraction of a country’s output aside as investment for the future and devoting more of the country’s productive capacity to manufacturing goods for current consumption. AIDS certainly affects the three ways to increase a country’s per capita consumption, because, by being a disease, it implies less working days, lesser opportunities to obtain better-paying jobs, and shorter working lives.(27)

It should be pointed out that AIDS has a much lower prevalence in developing countries than other diseases such as malaria, but its economic impact by case is greater for several reasons, among them, the following:

1) It mainly affects adults in their most productive years.

2) The infections resulting from HIV/AIDS lead to heavy demand for expensive treatments.

3) To the extent that the treatments fulfill their task, their prescription could be prolonged for lengthy periods.

4) The number of persons already infected with HIV who have still not developed AIDS is already of huge proportions (nearly 22 million people worldwide in 1996).

5) The number of HIV-infected persons is likely to continue to increase.

The relationship between underdevelopment and health is quite well known when talking about other pathologies. Concerning AIDS, not only do relationships exist which explain the greater growth in poor countries and marginal populations, but also deficient reactions are conditioned in facing the problem. The long history of poverty in the most affected countries makes one think that, even if the cure of AIDS should solely consist in drinking potable water, a large quantity of persons¾ mainly in developing countries¾ would not have access to that treatment.

The probable impact of AIDS on economic development has been debated at length. Thus, a common argument is that the economic impact of AIDS on developing countries does not really constitute an economic problem because ill or dead workers will be replaced by unemployed persons, owing to the abundance of cheap labor and high unemployment. This argument may be valid as long as there exists sufficient unemployed persons who wish to replace those who can no longer work due to AIDS. But even in countries with the highest unemployment rates, the labor "reserve army" is bound to disappear in the presence of a disease for which no cure exists, as is the case of AIDS. In the presence of a disease like AIDS, full employment could finally be achieved. However, if the cure continues to be non-existent or prohibitively expensive for developing countries, and if the number of AIDS cases grows more rapidly than the labor force, what would follow? Then, production will be negatively affected, since the labor force in the full-employment economy will begin to decline, with adverse consequences on social welfare.

The HIV/AIDS epidemic has a heavy macroeconomics impact, owing in part to the high costs of treatment which divert resources from productive investments. More specifically, the costs of HIV/AIDS are commonly classified as: a) direct, which are the costs of personal- and health-care that an infected individual needs, including non-personal services such as blood screening, health education, staff training, and research; b) indirect, which are the costs in terms of lost production due to morbidity and mortality caused by AIDS, including estimates for the value of unmarketed production, such as housekeeping tasks and subsistence agriculture; c) direct invisible costs, represented by services provided by family, friends and charities; although unpaid, these services represent a real consumption of resources, and hence a real cost, and their omission can lead to suboptimization in choosing between different care strategies; and d) indirect invisible costs, which are the costs of intangible reactions and lower quality of life through factors like pain, incapacity, fear, anxiety, isolation, stigma, depression, etcetera; these costs are obviously important in the case of AIDS, but it is very difficult to estimate them.

The potentially devastating effects of the HIV/AIDS epidemic can be averted with relatively modest resources. In fact, a country does not have to be rich to be successful in prevention efforts. The desirability of prevention in the case of HIV/AIDS is considerably important given the vast benefits of preventive action and the enormous future costs incurred in the absence of it. Since there is no vaccine or cure for AIDS, prevention is the only way to fight the epidemic.

Prevention involves relatively low costs and, if effectively implemented, yields enormous benefits. The World Bank reports that studies conducted in nine developing and seven industrialized countries suggest that preventing a case of AIDS saves, on average, an amount equivalent to about twice the GNP per capita in discounted lifetime costs of medical care, and in some urban areas the savings may be as much as five times the country’s GNP per capita. The benefits of prevention must also take into account that in the case of communicable diseases, and especially of epidemics like HIV infection, estimates must take into account the fact that each case prevented also prevents subsequent cases.(28)

The urgency of increasing prevention efforts becomes evident when we look at the projections available, which indicate that the HIV/AIDS epidemic has disastrous consequences that get worse with the passage of time.

From an economic standpoint, it is of utmost importance to increase without delay the prevention efforts, which involve a very modest cost when compared with the direct costs of an uncontrolled HIV/AIDS epidemic. The decision maker has the alternative of acting now using relatively little resources, or suffer tomorrow, having to use considerably higher amounts of resources. The costs of HIV/AIDS, by diverting scant resources in developing countries¾ precisely characterized by a scarcity of capital¾ are a matter of considerable importance.

In the United States, in 1991, the average annual cost of the medical-care management of each one of the AIDS cases was estimated to be US $38,000; assuming an increase in the annual cost of medical treatment of AIDS patients of 7 to 8% annually, for 1995 the annual cost per case would be US $120,000.(29)

For example, in 1991 it was found that the use of zidovudine in a patient without symptoms, a cost-effective intervention, since it prolongs life expectation and has a cost of approximately US $6,600 per life year gained, which compares favorably with other routine medical interventions such as heart surgery.(30)

Of the direct costs, the hospitalization cost¾ at the beginning of the epidemic¾ represented the greater part of the medical-care cost for AIDS patients. To the extent that ambulatory medical-care schemes are adopted, the costs of medications will account for the greater part.(31)

The direct cost of using three antiretrovirals¾ for example, AZT, DDC and saquinavir¾ could reach in Mexico, in mid-1996, an annualized cost of US $17,336. The cost of using prophylactic medications for other microorganisms would correspond to more modest amounts; for example, an annual US $50 for trimetroprim-sulfametoxazole used for the prophylaxis of P. Carinii and Toxoplasmosis, and US $800 for the use of azithromicin for the prevention of Mycobacterium avium. The use of prophylaxis varies according to the condition of the patients; however, often multiple medications are used for the prevention of opportunistic diseases, whereupon the cost of each prophylactic medication should be added to the list of direct costs involved in the provision of medical care for the affected.

It should be clear that the lack of an explicit medical care policy for AIDS patients or for the prevention of HIV infection does not imply that this epidemic will cease to cause expenses, both in the economy of countries and in health systems. In fact, the lack of a medical care and prevention policy for HIV/AIDS often is one of the most expensive strategies to face it. Indeed, the fact that persons who now become infected with HIV do not develop AIDS until many years later does not free today’s public-health authorities from their responsibility.

Expenditure on HIV/AIDS in Mexico, a case study

In an accounting exercise of amounts spent in Mexico for 1995, a study was carried out to provide a panorama of the estimated global amount of expenses by type and by source.(32,33) The mechanism for these estimates consisted, firstly, in the identifación of the institutions providing health-care for HIV/AIDS patients, the population covered by them, health-care and prescription patterns, and the funding sources of these institutions; also, preventive actions were listed, in addition to estimating their cost and financing source.

In broad terms, HIV/AIDS-related expenses were estimated to have amounted to US $79.1 million for 1995. The majority of these expenses were recorded in the item of medical care (85%) and in public sector expenditures. International contributions accounted for 1% of total expenses in this item and were earmarked essentially for prevention (Tables 2-4)

Table 2. Overall Health Expenditures by type and source of funding
Preliminary Estimates. Mexico, 1995. (million USD)

	Domestic Public	Domestic Private	International	TOTAL
Prevention	578.1 7%	86.0 1%	57.8 1%	721.9 9%
Treatment	5,331.0 65%	1641.0 20	28.9 <1%	7,000.9 85%
Mitigation	467.6 6%	0 0%	0 0%	467.6 6%
TOTAL	6,376.7 78%	1727.0 21%	86.7 1%	8,190.4

 

Table 3. Overall HIV/AIDS Expenditures by type and source of funding
Preliminary Estimates. Mexico, 1995 (million USD)

	Domestic Public	Domestic Private	International	TOTAL
Prevention	16.6 21%	11.9 15%	0.9 1%	29.4 9%
Treatment	24.0 30%	25.4 32%	0.0 0%	49.4 85%
Mitigation	0.2 <1%	0 0%	0 0%	0.2 6%
TOTAL	40.8 52%	37.3 47%	0.9 1%	79.1

 

Table 4. % Expenditures on Health and AIDS

	Domestic Public	Domestic Private	International	TOTAL
Prevention Health AIDS	7% 21%	1% 15%	1% 1%	9% 37%
Treatment Health AIDS	65% 30%	20% 32%	<1% 0%	85% 62%
Mitigation Health AIDS	6% <1%	0% 0%	0% 0%	6% <1%
TOTAL Health AIDS	78% 52%	21% 47%	1% 1%	8,190.4 79.1

Expenditures on prevention

In terms of prevention, spending amounted to approximately US $29.5 million. The expenses can be classified into the following two categories: blood-bank screening for the prevention of HIV blood transmission (US $16.4 million); and expenses on prevention of HIV sexual transmission (US $13 million). Blood-bank screening expenses were essentially charged to public expenditure (US $11 million), divided in equal parts among social security institutions (IMSS and ISSSTE) and, a lower amount (US $5.3 million), was spent by civil and private institutions, among them, mainly the Mexican Red Cross. (Table 5).

Table 5. Prevention expenditures by type and source
Mexico, 1995

	TOTAL	I,E & C	Blood Bank Screening	Condoms
DOMESTIC PUBLIC	16.6 (56%)	5.5 (19%)	11.1 (38%)	0 (0%)
Direct Government	7.8 (26%)	2.3 (8%)	5.5 (19%)	0
Social Security	8.8 (30%)	3.2 (11%)	5.5 (19%)	0
DOMESTIC PRIVATE	11.9 (40%)	4.0 (14%)	5.3 (18%)	2.6 (9%)
Out -of- Pocket	2.9 (10%)	0.3 (1%)	0	2.6 (9%)
Private Insurance	0 (%)
Employer	3.2 (11%)	3.2 (11%)	0	0
Non-Government Organization	5.8 (20. 0%)	0.5 (2%)	5.3 (18%)	0
INTERNATIONAL	0.9 (3%)	0.8 (3%)	0	0.1 (<1%)
TOTAL	29.5 (100%)	10.4 (35%)	16.4 (56%)	2.7 (9%)

The federal budget was the main source of expenditures on prevention of HIV sexual transmission. Additionally, non-governmental organizations provided, in an important way, services for the prevention of AIDS. The latter were considered as non-monetary expenses, given their difficult quantification, the difficulty in establishing their coverage, since such services are largely based on donations and on non-paying voluntary work.

Governmental expenditures for the prevention of HIV sexual transmission were estimated using, primarily, the budget of the National Council for the Prevention and Control of AIDS, which is the governmental agency with that specific mandate. It was not possible to identify other governmental financing sources for HIV sexual transmission prevention activities. However, upon the conclusion of the decentralization of the Health Secretariat, the respective funds are expected to be transferred, as, likewise, the responsibility for the planning and the implementation of these activities.

It should be noted that public outlays on information, education and communication were primarily financed through public expenditure (US $16.3 million), through private funds (US $11.9 million), and through contributions from international organizations (US $0.9 million). Of this total, direct out-of-pocket consumer expenses were estimated to be US $2.6 million, for direct purchase of condoms. Expenditures through non-government organizations were not easily quantified, and were not included in this estimate.

Expenditures on medical care

Given that medical-care outlays are not found available in any official source, these were estimated by establishing typical patterns of treatment for typical patients, by service providers (physicians) who cared for the highest proportions of patients. The cost of each treatment pattern was estimated using the average costs for each service; e.g., hospitalization day, medications, medical consultation, laboratory tests, etcetera. Finally, the cost of each treatment pattern was multiplied by the estimated number of patients in each health-care center of each institution. The resulting calculations took into account the differences by socio-economic status, social security entitlement, inclusion of medications in basic clinical manifestations or one’s access to them through subsidized prices, the patient’s clinical condition, etcetera.

In this way, outlays on HIV/AIDS treatment were estimated to total US $49 million; this figure was the result, in nearly equal parts, of out-of-pocket expenses of patients (US $25.4 million) and of public budget expenditures (US $24.0 million).

These outlays include the treatment considered optimum in 1995 (essentially the use of a combination of two antiretrovirals and prophylactic medications) for a minority of AIDS patients (approximately 38% of the estimated total number of survivors during that year). Asymptomatic seropositive persons generally receive neither the antiretroviral nor the prophylactic treatment. The treatment pattern outside of the large hospital centers in the big cities included a higher number of days of hospitalization and a lower use of medication.

The greater part of the out-of-pocket expenses correspond to the use of prophylactic medication or a second antiretroviral. Hospitalization expenses were paid primarily by social security institutions and, secondarily, from patients’ own funds. It is worth noting that out-of-pocket expenses¾ even though in the aggregate they account for nearly one-half of the expenses in this item¾ in general contribute to a suboptimum pattern of treatment for the majority of the patients; that is, this accounting includes expenses disbursed by beneficiaries additional to those contributed by their social security institution (e.g., nutritional supplements in cases of wasting syndrome), and others, the majority of non-beneficiaries, which include all expenses from those on antibiotics for prophylaxis to those on anti-retrovirals, fundamentally, purchased in a still-insufficient manner for a complete mono-therapy scheme.

Outlays on antiretrovirals contributed to an annual expenditure of US $20.5 million, paid for mainly by patients and by social security institutions. (Table 6)

Table 6. HIV/AIDS Treatment expenditures by type and source
Mexico, 1995

	Hospital	Clinic Visits	Anti retrovirals	Other Pharm	Labora-tory Tests	TOTAL
PUBLIC	4..8 (10%)	0.6 (1%)	9.9 (20%)	5.4 (11%)	3.3 (7%)	24.0 (49%)
Direct Government	0.5 (1%)	0.2 (<1%)	0.2 (<1%)	1.2 (2%)	1.8 (4%)	3.9 (8%)
Social Security	4.3 (9%)	0.4. (1%)	9.7 (20%)	4.2 (9%)	1.5 (3%)	20.1 (41%)
PRIVATE	1.5 (3%)	1.1 (2%)	10.6 (21%)	7.3 (15%)	4.8 (10%)	25.4 (51%)
Out -of-Pocket	1.5 (3%)	0.9 (2%)	10.6 (21%)	7.3 (15%)	4.8 (10%)	25.2 (51%)
Non- Government Organization	0 (0%)	0.2 (<1%)	0 (0%)	0	0	0.2 (<1%)
TOTAL	6.3 (13%)	1.7 (3%)	20.5 (41%)	12.7 (26%)	8.1 (16%)	49.4 (100%)

 

The role of governments in the prevention and care of AIDS(IV)

There are three different roles that governments assume, in different degrees, in the health-care sector: regulation, financing, and the provision of health services.

Not all governments provide health services in a direct way; all governments, however, finance health services in varying degrees and without a doubt all assume the regulation of anything which may cause harm or cause risk of loss of health as an intrinsic function of the state.

The regulating role of government in health matters is almost indisputable; however, on the issue of financing the provision of health services, there is much debate over which interventions should be financed. The direct provision of service by a country’s ministry of health has been highly questioned, particularly when comparing it to similar health services provided by private or non-profit institutions, which operate both in urban and in rural areas. Even so, the provision of adequate services to the affected population should be guaranteed, both under insurance schemes and in the case of the uninsured population.

One of the major components of health-care cost for AIDS patients is money spent on medication. In some Latin American and Caribbean countries, the National AIDS Programs furnish the necessary pharmaceutical products, including antiretroviral combinations, as well as the ambulatory and hospital care required for all patients diagnosed with AIDS (e.g., in Chile); in other countries that same care is furnished to all patients, provided they are covered by a social security system. As the number of cases increases, it is considered that both the former and the latter will run into budgetary problems in order to be able to absorb the costs of furnishing such care.

However, it is necessary to highlight that the financial solution of social security institutions is not to exclude HIV/AIDS from their treatment scheme or to provide the affected with suboptimal treatments. Adequate actuarial calculations will make it possible to provide care in keeping with the advance of medical technology, not only for AIDS but also for the care of other diseases.

It is worth noting, however, that social security institutions mainly invest in the treatment, frequently inadequate, of patients, and their preventive emphasis often includes only the control of blood banks. Their actions for the prevention of HIV sexual transmission are scant, inefficient and insufficient. Then it is clear, in the light of the insufficiency of preventive actions, that policies excluding the treatment of AIDS patients are more than informed decisions, moral sanctions against the sexual activity of the individuals.

Some alternatives for reducing health-care costs involve the adoption of ambulatory management schemes. Paradoxically, in places with less trained staff, and usually on a greater scarcity of medical resources, preference is given to hospitalization without antiretroviral treatment, resulting in higher cost and lower effectiveness.

The most serious problem concerns low-income patients who are not covered by any type of insurance, private or social security, and who live in countries in which their health-care costs will not be covered with public funds. In these cases, such persons shall have to turn to charity health-care schemes or enter into research protocols that normally provide, free-of-charge, the medications under study, albeit in no way do they constitute the optimum scheme for the provision of services to the disenfranchised population. Unfortunately, there are few alternatives for this type of patients, whereupon governments which do not cover these health-care costs should foster and encourage the care of disenfranchised patients by other mechanisms.

Despite its high cost, the treatment for HIV/AIDS is not the most expensive of those applied in medical and social security institutions. In this sense, governments should establish uniform guidelines for covering the costs of diseases among their patients, prior to eliminating resources for the care of AIDS. The message, then, is very simple: the coverage of diverse diseases must abide by the same guidelines of evaluation. If the financing of heart transplants, chemotherapy in certain cancers, bone marrow transplants or other interventions is not questioned, then the financing of antiretroviral treatment of AIDS patients should not be questioned.

That is to say, Latin American and Caribbean countries, unfortunately, still do not have sufficient resources to finance with public funds all their health problems at a level of access and quality similar to that prevailing in industrialized countries; therefore, in their reform processes, they will need to set priorities for the public financing of certain interventions over others and cover 100% of the cost of basic services for the care of low-income populations. The major issue of discussion, then, will lie in the definition of the basic packages and the guidelines used for determining their inclusion.

Special care should be taken over cost-benefit studies in the case of AIDS, since the great advances in antiretroviral therapeutics may have increased the costs and the benefits of its utilization.

By way of conclusion, the government’s first responsibility is to ensure at the national level that the blood banks are protected against the presence of HIV, with public or private financing. Moreover, it is the government’s obligation to guarantee for AIDS patients the same type of care that is given to patients with other chronic diseases, under the diverse schemes of coverage and provision of services in the countries. For example, one of the priorities, therefore, is to establish provisions for private insurance policies not to exclude coverage of AIDS. The government’s regulatory responsibility in these matters is indisputable. Likewise, the government’s intervention is necessary to stem HIV sexual transmission. However, this is a complex matter due to the possible interpretation of governmental actions as an intrusion in the private life of citizens. Although it does not correspond to the government to be the implementing agent of interventions, it is indeed its competence to foster and ensure that specific social groups become involved in the strategies for prevention and care.

In this sense, one of the major recommendations arising from international conferences on AIDS and from international agencies working on AIDS suggest that governments perform a promoting, regulatory and financing function of preventive interventions, by backing diverse social organizations that can work effectively and efficiently on the subject.

Even the lack of explicit policies is a policy. In terms of prevention and control of AIDS, the absence of activities in this particular respect is a policy of grave consequences in the medium and the long term

National governments have the obligation to undertake preventive actions against HIV transmission and to guarantee adequate care for the HIV-infected population and for those who are ill with AIDS, because it concerns a public-health problem. Not to do it, owing to the political costs that may be involved therewith, constitutes, at the present moment, a grave irresponsibility, putting in danger large sectors of the population, and thereby affecting the life of countries from the economic and social points of view.

Medical institutions, in turn, have the obligation to provide the best therapeutic treatment available, for which it is necessary to implement continuing training activities for their staff.

Regional approaches for combating HIV/AIDS

On January 1, 1996, the new Joint United Nations Programme on HIV/AIDS (UNAIDS) was implemented. This program is co-financed by the United Nations Development Program (UNDP), the United Nations Educational, Scientific and Cultural Organization (UNESCO), the United Nations Fund for Population Activities (UNFPA), the United Nations Children’s Fund (UNICEF), the World Health Organization (WHO); and the World Bank. The work of UNAIDS at the world level and at the country level has three mutually reinforcing functions: development of policies and research, technical support, and promotion. One of the central elements of these efforts is based on the biggest lesson learnt in the last decade: the HIV/AIDS epidemic is not just an epidemic outbreak.(34)

The characteristics of the HIV/AIDS transmission cause it not to display, in terms of epidemiological control, important geographical regional differences; rather, HIV extends beyond the boundaries of any country by multiple mechanisms, among them, migration and tourism. That is why the regional approach should be given overriding importance, not only in view of the antecedents of the disease, but primarily because of the means for its control, given the similarities in the area.

As was mentioned in this publication’s preface, the Fundación Mexicana para la Salud is the implementing agency of the SIDALAC initiative, which was originally promoted by the World Bank and now is part of UNAIDS. The general objective of SIDALAC is to contribute to the mobilization of national and international efforts in Latin America and the Caribbean against the AIDS and other STD epidemics, by promoting awareness among decision makers in the region, supporting the development of a new generation of programs for the control of AIDS, and supporting the development of specific regional approaches for Latin America and the Caribbean regarding the control of AIDS and of other sexually transmitted diseases.

As a result of this initiative, approaches are expected that, more than the sum of individual efforts of countries, shall contain in their perspective the notion of region, with its consequent coordination of activities and the mutual sharing of lessons-learned in neighboring countries.

Conclusions

HIV/AIDS is spreading at the same time that it is becoming endemic. To remain free from infection until one reaches maturity is a challenge of great magnitude in communities with a high HIV prevalence, since the preventive measures have had limited success mainly because the broader context or environment in which people live has not been appropriate for prevention.

The prevention and the treatment of the affected have been separated artificially. But for individuals and their families, as well as for communities, to face HIV infection is part of a long-term challenge peculiar to the AIDS era, a challenge which includes protecting oneself from HIV. We must integrate the aspects of prevention and health-care in such a way so that one can exploit the rich interface of both aspects. More and better quality interventions are needed throughout the prevention-care continuum. At the same time, the vulnerability of social action should be reduced, ranging from community mobilization to international initiatives.(34)

There are two levels of prevention: primary prevention prevents the occurrence of new infections; and secondary prevention reduces morbidity and mortality, once the infection is already present. Primary prevention has been achieved with the elimination of infected blood products, antiviral treatment to pregnant women with HIV infection, behavioral change programs to reduce high-risk practices, consistent use of condoms, the treatment and control of sexually transmitted diseases. Secondary prevention is aimed at interventions that help to reduce the progression of the HIV infection, delay the appearance of opportunistic infections and AIDS, and increase the survival and quality of life of infected patients. These interventions are based on timely and effective antiviral treatment, prophylactic treatment of opportunistic infections, improving nutrition, and managing the patient’s emotional state.

The struggle against the social vulnerability to the HIV infection is the struggle itself against the epidemic and corresponds to a long-term effort that is the responsibility of the current governments, although the length of their administration-terms may end before the beneficial effectos of such a policy are evident.

To achieve this objective, it is suggested to re-direct the existing resources in the different countries through the following actions:(VI)

1. To identify the epidemiological pattern of each country in order to determine populations at increased risk for HIV.

2. To identify civil and social groups and organizations that work currently with such populations.

3. To promote and strengthen such organizations for them to implement community-based prevention and care interventions, respecting the characteristics and specificities that such programs would need.

In their role of regulation of health and education policies, governments could implement such actions immediately through some or all of the following mechanisms:

1. Creation of a technical group composed of authorities, scholars and members of civil organizations, which would call for prevention projects against HIV, to be financially supported, after their assessment.

2. The role of this technical group would be to approve the proposals within an open contest, based on their quality.

3. To evaluate the proposals of groups in terms of the capability of organizations to account for the cost-effectiveness of their designs, their population coverage, and the recognized quality of work already carried out, as well as the theoretical base of the research and intervention proposals.

4. To implement coordination mechanisms with organizations, such as, institutional development, tax exemption mechanisms, agreements with social groups, or contracts or subcontracts, etcetera.

The strategy of involvement and coordination with civil and community organizations, combined with an overall public health and education policy, seems to be the most efficient to decrease virus transmission in a permanent and consistent manner. Social marketing has shown certain effectiveness in behavior change, but ephemeral. The costs of sustaining this kind of campaigns are too high and distract resources for other interventions of longer-term effectivity.

However, immediate actions are also required in order to know the impact of the epidemic and carry out preventive interventions. For this reason, it is suggested that governments commission a series of studies whose goals should be:

1. To carry out diagnosis of new infections.

2. To determine the future course of the epidemics and the subepidemics, and to determine those groups in urgent need of interventions.

3. To investigate quantitatively and qualitatively the structural determinants of the vulnerability of such groups to HIV infection and to inquire into the effectiveness of intervention models designed with the information produced by the studies described above.

 

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I This section is based on Chapter 2 of this publication, "Current State of Knowledge in Basic Sciences on HIV/AIDS" written by Luis Soto.

II This section is based on Chapter 3 of this publication, "Clinical Aspects of HIV Infection. Current Concepts 1996", written by Juan Sierra.

III This section is based on Chapter 4 of this publication, "Epidemiology and Public Health", written by Carlos Avila-Figueroa.

IV This section is based on Chapter 6 of this publication, "HIV/AIDS and Economic Development", written by Enrique González.

V This section is based on Chapter 7 of this publication, "HIV/AIDS and the Reform of the Health Care Systems of Latin America and the Caribbean", written by Jorge Saavedra.

VI This section is based on Chapter 5 of this publication, "Social Sciences and AIDS", written by Ana Amuchástegui-Herrera.

 

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