Human immunodeficiency virus (HIV) is the retro-virus responsible for the clinical spectrum of the acquired immunodeficiency syndrome (AIDS). Once infected by the virus, an individual is said to be HIV positive. HIV then attacks and progressively destroys key elements of the immune system, rendering victims susceptible to a host of opportunistic infections and rare cancers. The development of one or more of these characteristic illnesses is what defines AIDS. “HIV/AIDS” is used to refer to the entire spectrum of disease progression from onset of infection through the advanced stages of illness.
The emergence of HIV/AIDS grew into the first worldwide epidemic since the influenza outbreak of 1918 to 1919. Unlike influenza, which struck more or less uniformly, the epidemiology of HIV/AIDS has been remarkably varied and dependent on a complex array of sociocultural elements. Politics, poverty, sexual behavior, science, and gender all conspire to produce measurable disease effects on individuals, communities, and nations. The holistic perspective of contemporary anthropology is central to understanding and managing the enormous impact of this global pandemic.
Biology of HIV
The Virus
There are two primary subtypes of HIV, designated HIV-1 and HIV-2. HIV-1 is the predominant form worldwide, while HIV-2 is limited mostly to West Africa. Both belong to a broader family of retroviruses and contain two identical RNA strands as their genetic material. A unique enzyme, reverse transcriptase, allows retroviral RNA to be copied to DNA that then integrates within a host cell. The genomic organization of HIV is similar to other retroviruses but also has a striking predilection for genomic variability that contributes to diversity in phenotype and cell tropism. This genomic mutability is a major obstacle to the development of vaccines and effective antiviral therapies.
Infection and Life Cycle
The surface protein coat of HIV preferentially binds with a subset of circulating immune system cells known as T cells. T cells are essential for immunosurveillance and disease control, with a variety of important functions. Both T cells and macrophages (as well as some other cell populations) contain a high-affinity HIV receptor called the CD4 antigen. Once inside a host cell, HIV replication begins, and vast numbers of new particles are released, killing the host cell in the process. Newly created particles bind and infect other CD4 cells.
Clinical Phases
Acute infection is sometimes marked by “flu-like” symptoms known as the acute retroviral syndrome. Symptoms are often unrecognized by the victim or by health care professionals. The viral load is initially high, and people in this stage are capable of transmitting the virus to others. Antibodies are made to HIV but take weeks to months to develop. This interval between the onset of infection and the rise of measurable antibodies is referred to as the “window period,” a clinically important time where seronegative individuals can be infectious. The antibodies are usually detectable within 3 to 6 months.
As the immune defenses activate against HIV, a balance is struck between virus and host, but inexorably, the virus eliminates immune cells faster than they are replaced. The process can take several years. During this time, an infected individual is usually asymptomatic and can unknowingly spread the virus. A gradual fall in CD4 cells accurately reflects disease progression. CD4 counts normally range from 1,200 to 1,400 cells/mL. When HIV reduces those numbers to around 200/mL, opportunistic illnesses begin to appear and the person is said to have AIDS. In the absence of treatment, the prognosis from the onset of an AIDS-defining illness (or a CD4 count less than 200) to death is usually 2 to 24 months.
Transmission
Science has documented only three established modes of HIV transmission: (1) sexual intercourse with an infected partner, either via heterosexual or homosexual contact; (2) parenteral (blood-borne) exposure to contaminated blood, usually via transfusions or intravenous drug use; (3) perinatal spread from infected mother to fetus, either in utero or at birth or through breast-feeding. Within each of these modalities, there is a wide range of infectivity rates, depending on host, viral, and environmental factors. Interventions directed toward these exposures form the medical basis for most HIV control programs. Anthropologic research, however, further asks what political, economic, or behavioral factors exist to influence people’s willingness to accept such interventions.
Diagnosis, Treatment, Vaccines
Confirmation of HIV infection is made through a variety of laboratory testing methods. Samples are usually taken from blood but can also be taken from saliva or urine. Standard ELISA and western blot methods detect HIV antibodies but are usually not sensitive enough to detect early infection in the window period. When clinical suspicion is high, a viral-load assay using polymerase chain reaction (PCR) technology can identify an acute infection before antibodies are measurable. Although all the tests are very accurate, a thorough understanding of the natural history of HIV infection is crucial for correct test interpretation and awareness of various diagnostic pitfalls.
Once HIV is confirmed, testing can be done to determine the virus subtype and/or its genotypic resistance to antiviral drugs. Some of these measures, such as the quantitative viral load and CD4 counts, help predict a person’s survival time as well as his or her risk of an AIDS-defining illness.
From an anthropologic perspective, the treatment of HIV/AIDS involves a holistic approach that addresses the socioeconomic context of the individual and not merely the medical aspects. Recent advances in antiretroviral drug therapy, for example, have greatly improved survival times but raised a host of ethical questions regarding access, cost, monitoring, and research protocols. Pharmacologic therapies against HIV started with azidothymidine (AZT) in 1997 and have expanded to include over 20 agents currently licensed by the U.S. Food and Drug Administration, available in an array of combinations. While these agents have proved remarkably successful, results are tempered by the cost (up to $20,000/yr), the potential for multiple side effects and drug interactions, and complicated dosing regimens.
This increasing complexity has also meant that fewer health care providers are equipped with the necessary expertise and access to the best HIV/AIDS care, and thus treatment has been further restricted, with wide-ranging consequences.
In contrast to the success of the antiretroviral drugs, HIV vaccine development has yielded numerous biologic insights but no practical results. As an alternative, there has been success in some trials of antiretroviral prophylaxis, especially in the area of perinatal exposure. Prophylaxis has reduced the maternal-to-child transmission to less than 2% in developed countries, where mothers generally have access to medications and C-section expertise. The success rate is substantially reduced, however, in the developing world, where such infrastructure does not exist.
History of the Pandemic
The first cases of AIDS were reported in June 1981 by the U.S. Center for Disease Control (CDC). Physicians identified unexplained clusters of pneumocystis carinii pneumonia (PCP) and Kaposi’s sarcoma, two rare illnesses known to be associated with immunodeficiency from other causes. The outbreaks occurred in homosexual men and were described initially as “GRID,” or gay-related immunodeficiency disease. Subsequent investigations led to the discovery of a similar disease pattern in other groups, such as hemophiliacs and IV drug users, and the name was modified to acquired immunodeficiency syndrome, or AIDS.
Within 2 years, laboratories had isolated the HIV virus, and by 1985, the first serologic tests became available. Doctors could now establish HIV infection in patients without AIDS and effectively screen the supply of blood bank products.
HIV is currently thought to have evolved from the simian immunodeficiency virus (SIV) and is estimated to have first appeared in humans in the early 20th century. HIV-2 has proven to be less virulent than HIV-1 and remains confined largely to West Africa and India.
The current burden of HIV/AIDS is indeed staggering. 2004 data from the Joint United Nations Programme on HIV/AIDS (UNAIDS) estimated the global number of infections at 39 million. Over 20 million have already died, including 3.1 million in 2004. The seroprevalence among the living ranges from 0.2% in Oceania to 7% to 8% across sub-Saharan Africa. Many local communities have much higher prevalence rates. Around the world, the number of people with HIV continues to rise in every geographic region, including sharp increases in China, Eastern Europe, and parts of Asia. Women now represent 57% of adults with HIV in sub-Saharan Africa and 25% of the cases in the developed world. The increasing numbers of infected women implies an increase in perinatal acquisition.
Life expectancy has dropped by up to 15 years in some countries within Africa and the Caribbean. The number of AIDS orphans is estimated at 15 million. Despite the original description as a disease of homosexual men, 80% of global infections are now acquired heterosexually. Epidemics in Eastern Europe appear to be driven by increasing intravenous (IV) drug use, which also fuels epidemics in some areas of China and East Asia. The future of HIV/AIDS remains uncertain, given the mutability of the virus, the current limits of therapy, and the uneven application of control efforts to the culturally diverse populations of the world.
Anthropologic Perspectives
Anthropologic research methods, with their historical depth and engagement in society, culture, and evolution, have an almost limitless relevance to the global complexities of HIV/AIDS.
At the core, anthropology asks: Given our biological knowledge and the availability of effective medical and behavioral solutions, why does HIV continue to spread? What impacts does this have on human populations? These questions can be addressed in the context of individual behavior, moving to various risk groups, and ultimately to whole communities or regions. Clinical anthropologic subfields have been at work at each level.
Biological Anthropology
Biological anthropologists focus on the relationships between human biology and culture or disease spread. This approach has been especially important in examining the variables of HIV infectivity within different population groups. For example, within the three known modes of HIV transmission, infectivity rates vary widely. The risk of transmission from a contaminated needle stick injury is limited to less than 1%, while the risk of transmission from transfusion of infected blood products approaches 100%. Infectivity rates among IV drug users fluctuates in between. Likewise, the risk from receptive anal intercourse is higher than for other types of sexual transmission, and the presence of concomitant sexually transmitted diseases (STDs) (especially ulcerative genital diseases) is associated with yet higher risk. Mathematical and epidemiologic models have been used to evaluate these variables with a host of other factors, including number of exposures, the probability of encountering an infected partner, and the mutability and virulence of HIV strains. Physical anthropologists also address the coevolution of HIV in both human and other primate hosts.
Linguistic Anthropology
Linguistic anthropologists study the usage and meaning of language, both within and across cultures. Language studies have helped evaluate the way HIV and illness are perceived and acted upon, from isolated Asian hill tribes to urban gay men. One UNAIDS scholar has recently addressed the imperative for integrating indigenous African cultures to Western technological discourse through an effective “language policy.” Such a policy would allow modern ideas about HIV/AIDS to be better incorporated at the local level. The problem was contrasted with Asian countries, such as Japan and Singapore, where indigenous language and culture have been preserved while still absorbing the language of modern science.
Symbols such as the AIDS quilt have been studied to better understand societal mechanisms of grief and remembrance.
Cultural Anthropology
Methodologies from cultural anthropology have had tremendous influence on our understanding of HIV. The basic health belief model, developed in the 1950s, has been employed in various forms to obtain information about an individual’s perceived susceptibility, severity, benefits, and barriers regarding any threat to health. Standard ethnographies provided a framework for understanding which practices exist in a given culture that could contribute to disease spread, such as the Masai practice of brothers who take in widowed sisters-in-law. KABP surveys (Knowledge, Attitudes, Beliefs, Practices) have been widely applied to obtain data sets from which to analyze behaviors. These techniques helped identify such causal associations as the use of recreational drugs and heightened HIV transmission among gay men, as well as the ways in which HIV misinformation propagates stigma and discrimination by health care workers toward AIDS patients. Many of these surveys have emphasized how even sound practical knowledge of HIV and its effects has failed to translate to meaningful behavior change.
The development of rapid anthropologic assessment techniques, largely qualitative, has improved the acquisition of cost-effective comparative data that help govern priorities in many aid programs.
Anthropology and Policy
As if the challenges of data acquisition and interpretation were not enough, there remains the essential work of translating social knowledge and theory about HIV into political action. Social scientists of all brands have been consumed with the monumental tasks of advising governments, negotiating goals, and assessing results. The immediacy of the human suffering has given rise to AIDS activism and thereby also exposed the face of AIDS apathy. One of the most dramatic examples of political controversy has played out in South Africa, where government leaders actively resisted organization of a national antiretroviral treatment program until 2003. Their concerns were based partly on skepticism about Western-generated HIV information and the racist implications. South Africa’s president publicly questioned the profit motives of giant pharmaceutical companies. As the debate escalated with data from both within and outside the country, public policy slowly shifted to embrace antiretrovirals. Worldwide pressures also helped convince drug makers to lower prices and thus improve access in both rich and poor nations. Currently, however, only 4% to 5% of HIV patients in the developing world even have access to antiretroviral regimens, so the mandate to address this gap will require both political will and the necessary funding. Of course, political structures themselves will necessarily change, as HIV/AIDS continues to affect demographics and economics by claiming younger men and women, who traditionally make up the healthy skilled workforce.
References:
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- Farmer, P. (1999). Infections and inequalities: The modern plagues. Berkeley: University of California Press.
- Feldman, D. A., & Miller, J. W. (Eds.). (1998). The AIDS crisis: A documentary history. Westport, CT: Greenwood Press.
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- Piot, P., & Coll Seek, A. M. (2001). International response to the HIV/AIDS epidemic: Planning for success. Bulletin of the World Health Organization, 79, 1106-1112.
- Schoepf, B. G. (2001). International AIDS research in anthropology: Taking a critical perspective on the crisis. Annual Review of Anthropology, 30, 335-361.
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