The ABCs of HIV Prevention

• Background: The Decline of HIV Prevalence in Uganda
• Evidence From Other Countries
• High Risks Associated With Concurrent Partnerships
• Addressing the Context for HIV Infection

Abstinence from sexual activity, being faithful to a single partner, and correct and consistent condom use are three key behaviors that can prevent or reduce the likelihood of sexual transmission of HIV, the virus that causes AIDS. The balanced promotion of all of these behaviors is commonly known as the "ABC" approach — “A” for abstinence (or delayed sexual initiation among youth), “B” for being faithful (or reduction in number of sexual partners), and “C” for correct and consistent condom use, especially for casual sexual activity and other high-risk situations.

An increasing number of countries — including Uganda, Thailand, Kenya, Cambodia, Zimbabwe, India, Rwanda, Ethiopia, Dominican Republic, and Haiti — have experienced national or sub-national declines in HIV associated with the widespread adoption of “A,” “B,” and/or “C” prevention behaviors. ^(1-2)

In lower-prevalence epidemic settings, in which many infections are concentrated among high-risk populations, the declines were associated with the implementation of targeted, evidence-based prevention efforts to reduce HIV risk in these populations. ^(3-5)

In high-prevalence epidemics that are primarily sustained by sexual transmission of HIV in the general population, it has been more difficult to assess the contribution of specific program efforts, because HIV risk was likely reduced through a wide variety of influences that increased risk perception and produced population-level changes in sexual behavior. ⁽⁶⁾

HIV prevention efforts are complicated by the fact that the global pandemic is rooted in different causes in different settings. To prevent the sexual transmission of HIV, the U.S. Government, through the President’s Emergency Plan for AIDS Relief, supports the ABC approach because it can be used to target the sources of the most new infections in a given population, while still being tailored to meet the specific needs of the most at-risk or vulnerable individuals. Fundamental to this approach is the recognition that different settings will also feature different barriers to the adoption of ABC behaviors. Prevention programs must therefore be developed in collaboration with the communities they serve and must, in addition to promoting individual behavior change, address the social norms, environmental factors, and policies that contribute to new HIV infections.

Background: The Decline of HIV Prevalence in Uganda

	Figure A: Uganda Median HIV Prevalence Among Pregnant Women 1985-2001

As one of the world's earliest — and probably most dramatic — success stories in confronting AIDS, Uganda experienced substantial declines in HIV prevalence during the 1990s. According to estimates by the U.S. Census Bureau and UNAIDS, national prevalence peaked at around 15 percent in the early ’90s and fell to 6.5 percent by 2004. Among pregnant women in Kampala, prevalence declined from a high of approximately 30 percent to about 10 percent, while among pregnant women in other areas it fell from more than 10 to less than 5 percent (figure A). ^(8-11) Uganda's marked decline in HIV prevalence remains unique worldwide. In most other sub-Saharan African countries with epidemics of comparable severity and longevity, similar declines have yet to occur (although promising trends have been observed in a still small but growing number of other countries). Accordingly, Uganda's success has been the subject of intense study and analysis.

It appears that Uganda's decline in HIV prevalence was associated with positive changes in all three ABC behaviors: increased abstinence, including delayed and considerably reduced levels of sexual activity by youth since the late 1980s; increased faithfulness and partner reduction behaviors; and increased condom use by casual partners. The most significant of these appear to be faithfulness or partner reduction behaviors by Ugandan men and women, whose reported casual sex encounters declined by well over 50 percent in World Health Organization surveys conducted in 1989 and 1995. ^(8-11) This conclusion is supported by comparisons with other African countries.

Uganda's successful combination of ABC strategies was rooted in a community-based national response in which both the governmental and nongovernmental sectors (including faith-based, women's, and other grassroots organizations) succeeded at reaching different population groups with different messages and interventions appropriate to their need and ability to respond. ^{(9, 11-12)}a Young persons who had not yet begun to have sex were cautioned to wait, and if a young person had just begun to have sex, he or she was urged to return to secondary abstinence. If a person was already sexually active, he or she was urged to adopt the practice referred to locally as "zero grazing" — faithfulness in marriage or partner reduction outside of marriage. For those who continued to engage in risky behavior, condom use was encouraged to reduce their risk.

Evidence From Other Countries

	Figure B: Uganda Reported Casual Sex in Past 12 Months 1989-1995
	Figure C: Northern Thailand HIV Prevalence & Behavior Changes, Military Recruits 1990-1995

While Uganda provides one of the most dramatic examples of the effect of ABC behavior changes on slowing the spread of HIV infection, there is growing evidence from other countries as well. In Thailand, the first Asian country to face a serious AIDS epidemic, prostitution was the main source of HIV infection. In the early 1990s, the government instituted a "100 percent condom use" policy in brothels, which was widely credited with sharply reducing the spread of HIV infection. Between 1990 and 1995, the proportion of men reporting paying for sex declined by more than 50 percent (figure C). In this more concentrated epidemic, therefore, partner reduction along with condom use for commercial sex undoubtedly had a substantial effect on slowing HIV transmission. ^(3-4) As in Uganda, the government's willingness to address the epidemic openly was also essential.

Kenya, Cambodia, and the Dominican Republic are other countries in which various combinations of ABC behavioral changes appear to have contributed to declines in HIV prevalence. In Kenya, there has been a marked decline in prevalence in recent years, ⁽¹⁾ during which time national surveys have reported clear, positive changes in sexual behavior (figure D). Cambodia is replicating Thailand's success in applying a 100 percent condom policy in brothels. Also similar to Thailand, the country experienced a steep decline in the number of men paying for sex (from 27 to 11 percent between 1996 and 2000). ^(4-5)

Figure D: Kenya - Changes in "ABC" indicators between the 1998 and 2003 Demographic and Health Surveys (DHS)

High Risks Associated With Concurrent Partnerships

Emerging evidence suggests that a substantial proportion of new HIV infections in high-prevalence epidemics results from concurrent or overlapping sexual partnerships. One reason for this is that the burden of HIV virus goes up dramatically during the first three to four weeks of being infected, as well as during the late stages of HIV infection and progression to AIDS (although to not quite the same dramatically high level as during early infection), making the likelihood of sexual transmission to an uninfected partner 10 to 100 or more times more likely during these periods. ^(15-18)

By using prevention resources to amplify culturally appropriate social sanctions against overlapping partnerships and infidelity, it may be possible to dramatically reduce the number of new infections, including the substantial proportion which take place during the initial three to four week ”acute” period during which HIV transmission is most likely to take place. Although current counseling and testing methodologies are limited in their ability to detect infection during the acute period,19 the scale-up of HIV counseling and testing services for couples can also afford an important opportunity to provide tailored prevention approaches to help prevent further HIV transmission both within, and outside of, discordant couples.

Addressing the Context for HIV Infection

Promoting behavior change entails addressing the social norms and environmental characteristics that may prevent individuals from protecting themselves. Therefore, it is important to recognize that the proper implementation of the ABC approach extends far beyond simply advocating for “A”, “B”, and “C”. For example, in many countries, young girls and women are particularly vulnerable to HIV infection because of existing norms favoring cross-generational sex. Infection rates among young girls are often many times higher than those among their male peers, and infection rates among older men are commonly higher still, making them particularly risky partners. To reduce the infection risks faced by these young girls, programs that attempt to address these norms, and particularly to target the attitudes and behaviors of their older male partners, may help make the promotion of the ABCs of behavior change more feasible and effective.

In September 2002, USAID hosted a meeting of technical experts from HIV/AIDS programs and research institutions to consider the evidence regarding ABC behavior change approaches to HIV prevention. The meeting identified areas of consensus that may have important implications for program planning and decision making: ⁽⁶⁾

• The mix of A, B, and C interventions needs to be tailored to local circumstances. In regions such as Southeast Asia, HIV is still largely confined to high-risk populations. In many African countries,
  
  
• the epidemic is generalized throughout the population. Approaches should be combined as appropriate based on the local cultural context as well as the state of the AIDS epidemic.
  
  
• Interventions need to be targeted for efficiency and respond to crucial differences among target groups. For example, balanced ABC approaches might be implemented in the form of youth interventions mainly emphasizing sexual deferral; interventions for sexually active adults mainly promoting fidelity or partner reduction to those not in monogamous relationships; and interventions promoting correct and consistent condom use to highly sexually active groups, especially sex workers and their clients, as well as people living with HIV/AIDS.
  
  
• Political leadership and community involvement are key. There is a critical need for government and community leaders to promote open communication about the problem of HIV/AIDS, address stigma, help empower women and girls to avoid sexual coercion, and develop a multisectoral response to enhance the success of ABC behavior changes.
  
  
• Further research is needed. Continuing studies in other countries will yield more evidence of the most effective balance of ABC approaches in different settings. Senegal, for example, appears to have achieved Uganda-like behavior change with a balanced ABC program in a low-prevalence setting. Further study of such successes is needed to consider their potential application elsewhere.

The USAID meeting also noted that the ABC approach to HIV prevention has ample room for the participation of a diverse range of partners in the global fight against HIV/AIDS. The approach helps clarify the complementary roles of program partners in overcoming the epidemic, and all partners — governments, international organizations, donor agencies, faith-based and other nongovernmental organizations, and many others — can contribute to ABC programming according to their particular organizational orientation, capacity, and strengths. This enhanced collaboration will serve to broaden the ABC strategy and maximize its impact across a wide spectrum of program and national needs.

August 2006

References:

1. Hallett TB, Aberle-Grasse J, Bello G, Boulos LM, Cayemittes MP, Cheluget B, Chipeta J, Dorrington R, Dube S, Ekra AK, Garcia-Calleja JM, Garnett GP, Greby S, Gregson S, Grove JT, Hader S, Hanson J, Hladik W, Ismail S, Kassim S, Kirungi W, Kouassi L, Mahomva A, Marum L, Maurice C, Nolan M, Rehle T, Stover J, Walker N. Declines in HIV prevalence can be associated with changing sexual behaviour in Uganda, urban Kenya, Zimbabwe, and urban Haiti. Sex Transm Infect. 2006 Apr;82 Suppl 1:i1-8.
   
   
2. Shelton JD, Halperin DT, Wilson D. Has global HIV incidence peaked? Lancet. 2006 Apr 8;367(9517):1120-2.
   
   
3. Celentano DD, Nelson KE, Lyles CM, Beyrer C, Eiumtrakul S, Go VF, Kuntolbutra S, Khamboonruang C. Decreasing incidence of HIV and sexually transmitted diseases in young Thai men: evidence for success of the HIV/AIDS control and prevention program. AIDS. 1998 Mar 26;12(5):F29-36.
   
   
4. Cohen J. Two hard-hit countries offer rare success stories. Science. 2003 Sept 19; 301(5640): 1659-1662.
   
   
5. Saphonn V, Parekh BS, Dobbs T, Mean C, Bun LH, Ly SP, Heng S, Detels R. Trends of HIV-1 seroincidence among HIV-1 sentinel surveillance groups in Cambodia, 1999-2002. J Acquir Immune Defic Syndr. 2005 Aug 15;39(5):587-92.
   
   
6. USAID. The "ABCs" of HIV prevention: Report of a USAID technical meeting on behavior change approaches to primary prevention of HIV/AIDS. Washington, D.C.: Population, Health and Nutrition Information Project, 2003.
   
   
7. Shelton JD, Halperin D, Nantulya V, Potts M, Gayle HD, Holmes KK. Partner reduction is crucial for balanced “ABC” approach to HIV prevention. BMJ 2004; 328: 891–93.
   
   
8. Bessinger R, Akwara P, Halperin D. Sexual behavior, HIV and fertility trends: A comparative analysis of six countries. Phase I of the ABC Study. Washington, D.C.: Measure Evaluation/USAID, 2003.
   
   
9. Stoneburner R, Low-Beer D. Population-level HIV declines and behavioral risk avoidance in Uganda. Science 2004; 304: 714-18.
   
   
10. Green, E.C., Halperin, D.T., Nantulya, V., Hogle, J.A. Uganda’s HIV prevention success: The role of sexual behavior change and the national response. AIDS and Behavior (in press).
    
    
11. Low-Beer D, Stoneburner RL. Behaviour and communication change in reducing HIV: Is Uganda unique? African J AIDS Research 2003;2:9-21.
    
    
12. Wilson D. Partner reduction and the prevention of HIV/AIDS. BMJ. 2004 Apr 10;328(7444):848-9.
    
    
13. Halperin DT, Epstein H. Concurrent sexual partnerships help to explain Africa's high HIV prevalence: implications for prevention. Lancet 2004 Jul 3-9;364(9428):4-6.
    
    
14. Halperin DT, Steiner M, Cassell MM, Green EC, Hearst N, Kirby D, et al. The time has come for common ground on preventing sexual transmission of HIV. Lancet 2004; 364: 1913-15.
    
    
15. Hayes R, Weiss H. Epidemiology. Understanding HIV epidemic trends in Africa. Science 2006 Feb 3;311(5761):620-17.
    
    
16. Hudson CP. AIDS in rural Africa: a paradigm for HIV-1 prevention. Int J STD AIDS. 1996 Jul;7(4):236-43.
    
    
17. Koopman JS, Jacquez JA, Welch GW, Simon CP, Foxman B, Pollock SM, Barth-Jones D, Adams AL, Lange K. The role of early HIV infection in the spread of HIV through populations. J Acquir Immune Defic Syndr Hum Retrovirol. 1997 Mar 1;14(3):249-58.
    
    
18. Galvin SR, Cohen MS. The role of sexually transmitted diseases in HIV transmission. Nat Rev Microbiol. 2004 Jan;2(1):33-42.
    
    
19. Fiebig EW, Wright DJ, Rawal BD, Garrett PE, Schumacher RT, Peddada L, Heldebrant C, Smith R, Conrad A, Kleinman SH, Busch MP. Dynamics of HIV viremia and antibody seroconversion in plasma donors: implications for diagnosis and staging of primary HIV infection. AIDS 2003 Sep 5;17(13):1871-9.