FL: HIV, 3 unitsPage 10 of 14

8. HIV Prevention

Many are seeking to address the HIV epidemic through prevention programs. These efforts include national, international, and local programs. A bright spot on the horizon is the possibility of a vaccine.

Potential Vaccine in the Pipeline

As noted in the bulletin at the top of the course, there is growing confidence that in the future a vaccine for HIV may be able to “remove the HIV virus from the body.” For a video issued in September 2013 by Louis Picker, associate director of the Oregon Health and Science University’s Vaccine and Gene Therapy Institute, click here.

National Strategy and High-Impact Prevention

A conservative estimate for the period 1991 to 2006 finds that in the United States prevention has already averted more than 350,000 HIV infections. The nation’s HIV prevention efforts are guided by a single, ambitious strategy for combating the epidemic: the National HIV/AIDS Strategy (NHAS). Recent scientific breakthroughs and growing leadership and momentum among some of the hardest hit communities bode well for change (CDC, 2013e).

Many challenges remain and by CDC’s latest estimates, approximately 50,000 Americans become infected with HIV annually, and 16,000 people with AIDS died in 2008. As a result, the number of people living with HIV in the United States, now at nearly 1.2 million, continues to grow by tens of thousands each year, creating more opportunities for HIV transmission. And a range of social, economic, and demographic factors affect some Americans’ risk for HIV, such as stigma, discrimination, income, education, and geographic region (CDC, 2013e).

To address the continuing challenges, CDC and its partners are pursuing a High-Impact Prevention approach to reducing new HIV infections. High-Impact Prevention refers to use of combinations of scientifically proven, cost-effective, and scalable interventions targeted to the right populations in the right geographic areas, and is intended to increase the impact of HIV prevention efforts—an essential step in achieving the goals of NHAS (CDC, 2013e).

This approach is designed to maximize the impact of prevention efforts for all Americans at risk for HIV infection, including gay and bisexual men, communities of color, women, injection drug users, transgender women and men and youth (CDC, 2013e).

Syringe Exchange Programs

Syringe exchange programs (SEPs) provide free sterile syringes in exchange for used syringes to reduce transmission of bloodborne pathogens among injection-drug users. SEPs in the United States began as a way to prevent the spread of HIV and other bloodborne infections such as HBV and HBC. The National Institute on Drug Abuse recommends that people who continue to inject drugs use a new, sterile syringe for each injection. As of November 2007, a total of 185 SEPs were operating in 36 states, the District of Columbia, and Puerto Rico (CDC, 2007). A ban on the use of federal money for these programs was reinstated in 2012, and SEPs are banned in the state of Florida. However, efforts were mounted in the state legislature 2013 to establish a five-year pilot program to legalize SEPs (Adams, 2010; Burch, 2013; CDC, 2010/2012).

Behavior Change and HIV Prevention

In instances where national epidemics have been reversed, a number of evidence-based studies have shown that broad-based behavioral changes were central to success. Hundreds of randomized controlled trials have demonstrated that individual, small group, and community-level interventions can generate safer behaviors (Working Group, 2008).

Studies in low- and middle-income countries among young people, sex workers, and other populations have demonstrated that prevention programs have the ability to change sexual and drug-use behaviors in resource-limited settings to prevent HIV transmission. The prevention programs have used the following approaches to prevent HIV infection:

  • Programs are targeted to individual behavior.
  • Emphasis is on broad-based efforts to alter social norms and address the underlying drivers of the epidemic.

In addition, there is effective use of available tools such as:

  • Treatment of sexually transmitted infections
  • Medical male circumcision
  • Substitution therapy for chemical dependence
  • Programs that provide access to clean injecting equipment

Using these and other interventions aimed at behavioral change, several countries—Brazil, Australia, Uganda, Thailand, and Senegal, among others—have had dramatic successes in curbing the spread of HIV within their borders. Together, these examples suggest that countries in a wide variety of settings have contributed to changes in HIV risk behaviors and, in doing so, have saved countless lives by averting HIV transmission. Based on the totality of epidemiologic evidence, it appears that national implementation of evidence-informed combination HIV prevention efforts in the 1990s was associated with a 50% to 90% decline in HIV incidence and prevalence in key populations (Working Group, 2008).


In Brazil public health campaigns have encouraged discussion of HIV, including frank public-awareness campaigns, condom promotion, focused behavioral interventions, syringe and needle exchange, school-based HIV education, prevention services in prisons, and voluntary HIV counseling and testing. Brazil has been particularly successful in reversing a serious epidemic among injection drug users. Condom use increased by almost 50% among sexually active adults between 1998 and 2005, and focused behavior change prevention programs helped maintain HIV prevalence at low levels among sex workers. Although the World Bank had predicted in 1990 that 1.2 million Brazilians would be infected by 2000, fewer than 600,000 were living with HIV in 2002 (Working Group, 2008).


In Australia, public awareness campaigns have focused on behavioral interventions among gay men, syringe exchange programs, and voluntary counseling and testing for HIV. As a result of Australia’s early, comprehensive response, focused largely on behavior change, annual HIV incidence peaked in 1985 and declined through the end of the 1990s. Between 1990 and 2000, the annual number of new HIV diagnoses fell by half (Working Group, 2008).


In what is perhaps the world’s best-documented national prevention success, Uganda began in the mid-1980s to address the rapid spread of HIV. It implemented public-awareness campaigns that encouraged young people to delay initiation of sex and urged sexually active adults to reduce the number of sex partners. In the 1990s, the country supplemented these early measures with condom promotion and investment in voluntary counseling and testing. From the earliest years, community-generated programs played a major role in the country’s AIDS response.

The results of these efforts were remarkable. The percentage of young people who were sexually active fell by more than half between 1989 and 1995, and Ugandans were significantly less likely to have multiple sex partners than people living in neighboring countries. Increases in condom use in the 1990s helped preserve and accelerate early prevention gains. By the late 1990s, infection levels in capital city Kampala had fallen by two-thirds, and national HIV prevalence had been cut in half (Working Group, 2008).


In Thailand the annual incidence of HIV has declined from 143,000 in 1991 to 19,000 in 2003 through the country’s innovative 100% condom program, which promoted the use of condoms in brothels. The government also promoted public education about HIV and fair treatment of those infected with the virus. Had Thailand not brought comprehensive HIV prevention to scale, it would now have 7.7 million HIV infections, rather than the estimated 580,000 residents currently living with HIV (Working Group, 2008).


In Senegal, early investment in awareness-raising, condom promotion, intensive prevention services for populations at greatest risk, and engagement of community leaders and faith-based organizations, combined with high rates of medical male circumcision, succeeded in keeping national HIV prevalence below 1% when neighboring countries experienced significant increases in infections (Working Group, 2008).