Resurgence of HIV infection

en who have sex with men (MSM) have been disproportionately represented throughout the HIV/AIDS epidemic in the United States (1). MSM and their communities are credited with making major reductions in and sustaining relatively low levels of risky sexual behavior for many years during the 1980s (2-5) and perhaps into the 1990s. Indicators since the mid-1990s, however, suggest a potential resurgence of HIV infections among MSM in the United States (6). Risky sexual behavior has been on the rise among MSM for a number of years (7) as has the incidence of sexually transmitted diseases (STDs) other than HIV (7-9); in fact, STD incidence was higher among people with AIDS taking highly active antiretroviral therapy (HAART) than among those who were not (10). Some health jurisdictions have even reported new increases in HIV incidence among MSM (11-12). Further, a recent study found intentional unprotected anal sex with a nonprimary partner ("barebacking") not uncommon in a sample of MSM (13); barebacking is contextually different from spontaneous unsafe sex that is a result of poor planning and from "negotiated safety" with a primary partner (14-15).

Distinguishing between epidemics

There has been an overall shift in the HIV/AIDS epidemic in the United States, a shift that is somewhat similar to that in San Francisco as described by Katz and colleagues (16). Before the widespread use of effective antiretroviral treatments, HIV/AIDS in the United States was viewed largely as an AIDS epidemic. Death rates were relatively high (1) and the incidence of risky sexual behavior was relatively low (17) among MSM, who were in danger of acquiring a terminal disease that often—especially early in the epidemic—encountered morbidity and progressed to death within several years (18-20). Since HAART became available in the mid-1990s (21), HIV/AIDS has come to be viewed more like a chronic disease. According to the most recent available national statistics, annual AIDS deaths of MSM in the United States have declined nearly 80%—from more than 25,000 in 1995 to less than 5500 in 2000 (1). This decrease mirrors a large increase in the number of MSM living with AIDS during the same period—from approximately 100,000 in 1995 to over 150,000 in 2000 (1). Although HIV treatments are not effective for, adhered to, or tolerated by everyone over time (22-24), many promising new drugs are being developed (25), so a relatively low incidence of AIDS deaths may continue in the future. The dramatic decline in AIDS deaths and the simultaneous increase in MSM living with AIDS signifies that HAART has changed the epidemic in the United States. The HIV epidemic now faces challenges that other preventable chronic diseases (e.g., heart disease, diabetes) similarly rooted in behavior choices have faced for decades (26-28). The challenge for prevention is that people appear to be more likely to knowingly put themselves at risk for a disease if morbidity and mortality from that disease are relatively distant outcomes.

Many MSM, HIV-negative as well as HIV-positive, acknowledge that their risky behavior has increased as a result of the availability of HAART (16, 29-31). Kalichman and colleagues (29) reported that gay and bisexual men who had unprotected receptive anal sex were more likely to say that new HIV treatments relieve their worries about unsafe sex. Similarly, Murphy and colleagues (31) found that beliefs that protease inhibitors enhance the quality and the length of life correlated with recent risky sexual behavior among HIV-positive and HIV-negative gay and bisexual men. According to another study (13), even those who engaged in barebacking (compared with those who did not) agreed that improved treatments had led them to have unprotected sex more often.

Further, some MSM identify competing needs (e.g., physical stimulation, emotional connection) as motivators for seeking anal sex without a condom (13); thus, for some men at some times, other needs may be equally or more important than preventing HIV infection. In the current HIV epidemic, a byproduct of HIV treatment is an increasing range and number of physical, mental, and social needs that compete with the need to prevent HIV infection, as long as effective HIV treatments are available and accessible to the public. These findings suggest that beliefs about the effectiveness of HIV treatments and the relative importance of other needs may be linked to more instances of risky sexual behavior.

Current biomedical preventions

The shift from an AIDS epidemic to an HIV epidemic in the United States poses a scientific challenge for assessing and subsequently disseminating effective vaccines and microbicides. Studies have demonstrated that the willingness to participate in vaccine trials may be associated with risky sexual behavior (32) and, further, that MSM participants who perceive that they are in the vaccine arm of a clinical trial (compared to MSM who perceive that they are in the placebo arm or who are unsure) report higher rates of risky sexual behavior during the study (33); participants in vaccine trials may engage in more risky sexual behavior during the trial at least partly because they are optimistic about a vaccine (34). Similar results were reported from a feasibility study of a hypothetical microbicide product for rectal use (35): The use of a partially effective microbicide could offer a net gain in risk reduction for MSM communities, however, some men may increase their individual risk for HIV infection. This may increasingly be true as biomedical interventions and treatments become available.

Paradigm shift for prevention

HIV prevention strategies for MSM, by and large, have not changed to reflect the dramatic shift in the epidemic. A shift in HIV prevention is needed on two main fronts.

Tandem biomedical and behavioral prevention. We need more purposeful tandem research on biomedical and behavioral issues. Because it is believed that early generations of available vaccines (36-38) and microbicides (39-40) will be less effective than condoms—estimated to be approximately 90% to 95% effective (41-43)—condom use will continue to be the prevention standard and a primary component of prevention messages. More behavioral research is needed to develop effective multicomponent prevention messages in preparation for a partially effective vaccine or microbicide. As a simple example, how might the following multicomponent message translate into behavior at the population level? "Used correctly, product X may be protective against HIV infection 50% of the time during anal sex, and condoms may be protective against HIV infection 95% of the time." Similarly, although enhanced biomedical efforts are needed to develop even more effective HIV treatments, behavioral research is needed to maximize product uptake and adherence to it.

Behavioral prevention. Behavioral interventions are needed to reduce the risk for HIV infection in the era of an HIV epidemic; that is, we need to reassess the scope of current prevention messages for MSM that were developed for an AIDS epidemic (e.g., always use a condom). Messages that were effective in the old epidemic may be less so in the current epidemic for a variety of reasons that center on the perception and the epidemiologic reality that HIV, largely, has become a manageable chronic disease. Thus, in addition to developing effective multicomponent prevention messages in preparation for a partially effective vaccine or microbicide, research is needed to develop multicomponent prevention messages that incorporate effective behavioral strategies that MSM may already be using. One example is "Use a condom unless you are in the context of ‘negotiated safety’ (i.e., an HIV-concordant primary partnership in which partners are periodically tested for HIV, agree to no risk behavior outside the partnership, and participate in ongoing reassessment of this agreement)." Although there is understandable concern that multicomponent messages may dilute the primary message and prevention standard (i.e., always use a condom), acknowledging effective strategies with specific guidelines may not only provide options directly but may also enhance the credibility of message senders and perhaps indirectly increase condom use in the highest risk contexts. Research is needed to assess the net gain of multicomponent messages that build contextual options for risk reduction as well as the credibility of message senders.

In addition, behavioral research is needed to assess entirely new approaches to HIV prevention in a chronic disease epidemic. These new approaches could be described as a shift from disease prevention in an AIDS epidemic to health promotion in an HIV epidemic. Rather than a single, specific disease prevention program, broad health promotion and healthy lifestyle programs may be beneficial. Broad health promotion programs would address HIV prevention in the context of other important health issues (e.g., substance use, depression, personal safety), promoting a general approach to health decision-making in one’s life (44). Healthy lifestyle interventions would address the complexities of individual physical, mental, and social needs (e.g., need for self-protection, need for intimacy, need for physical pleasure) and would consider the individual to be multidimensional. In fact, there is evidence that health behaviors may be linked (45-48); that is, broad health promotion or healthy lifestyle programs may work to prevent chronic diseases and other health concerns (49-51).

In sum, public health and research efforts are needed to respond to recent increases in risky sexual behavior and the incidence of STDs—including HIV infections—among MSM, a population that continues to be disproportionately affected by HIV/AIDS in the United States. As responsive scientists, prevention specialists, and health officials, we must heed the call for change and work alongside MSM communities for a successful shift in HIV prevention that reflects the epidemiologic shift that has become a reality.

References