Prevention, care and support: strategies for change
HIV/AIDS may not be curable, but it is certainly preventable and treatable. It has been estimated that almost two-thirds of the new infections projected to occur during the period 2002–2010 can be prevented if the coverage of existing HIV prevention strategies is substantially increased (41). Prevention efforts can and do work to halt the spread of the virus, and real advances in treatment hold out the hope of longer and better lives for those already infected. Scaling up treatment must become a way to support and strengthen prevention programmes. Careful integration of prevention and treatment services will ensure that those who test positive are linked to counselling and treatment, which can lead them to protect others from infection (42). Furthermore, people who might otherwise be afraid to undergo testing are more likely to seek services for sexually transmitted infections and HIV/AIDS when they have access to treatment (see Box 1.3).
Preventing the sexual transmission of HIV
Prevention approaches can work in many populations, as long as they use evidence-based strategies, carefully tailored to the social and economic settings in which they are implemented and to the state of national HIV/AIDS epidemics. A comprehensive approach that supports social and individual rights, involves communities and is developed on the basis of their cultural values has been found to be effective when combined with the promotion of consistent condom use, voluntary testing and counselling for HIV, and delayed sexual initiation. Promotion of other strategies, such as abstinence and reduction in number of partners, also needs to be based on firm evidence.
Level of social and economic development, and cultural factors such as gender inequality or access to education and health care, are all known to be obstacles to the successful implementation of prevention initiatives. Interventions that reduce the effects of such obstacles – by implementing measures that allow girls to stay in school for longer, for example – can have a lasting impact on rates of HIV transmission. The promotion of human rights, combined with behavioural change programmes, also helps (45, 46). Lessons learnt from various settings and communities show that the use of any chosen prevention measure requires that people not only have the proper knowledge but also the ability to apply it.
Consistent condom use demands a reliable distribution system to people who live in poverty or in difficult-to-reach areas (47). Interventions that have targeted populations at high risk such as men who have sex with men and female sex workers and their clients in Africa, Asia and Latin America are effective. In Abidjan (Côte d’Ivoire) and Cotonou (Benin), HIV prevalence among sex workers declined during the 1990s and the increased use of condoms contributed significantly to these declines (48, 49); similar changes have been observed in sex workers in Cambodia and Thailand (see Box 1.4). Evidence from a South African mining community showed that interventions among those most at risk increased condom use and greatly reduced rates of sexually transmitted infections – especially those most linked to HIV transmission – in the community (52).
Effective prevention programmes aimed at young people can teach them responsible and safe sexual behaviour, according to some of the latest research. Recent findings from Uganda indicate that young people have changed their behaviour considerably over the last few years, and that HIV prevalence among them has dropped (53).
Breaking the link with other sexually transmitted infections
Sexually transmitted infections increase the risk of HIV transmission by at least two to five times (49). They help drive the spread of HIV. If untreated, they not only increase the infectivity of HIV-positive individuals but also make those who are HIV negative more susceptible to infection. Early detection and treatment, and related efforts to reduce the prevalence of these infections, should therefore be an integral component of a comprehensive HIV prevention effort. The potential benefits are probably greatest in the early stages of a national HIV/AIDS epidemic when the virus spreads as a result of high rates of change of sexual partners, but evidence suggests that measures to control sexually transmitted infections have important effects even in more advanced epidemics.
Preventing infection in infants and children
Every year an estimated 2.2 million pregnant women infected with HIV give birth, and about 700 000 neonates contract HIV from their mothers. HIV transmission from mother to child may occur during pregnancy, labour and delivery, or during breastfeeding. In the absence of any intervention, 14–25% of children born to HIV-infected mothers become infected in developed countries, 13–42% in other countries (54). This disparity is mostly a result of different breastfeeding practices. It is estimated that 5–20% of infants born to HIV-infected women acquire infection through breastfeeding.
The most effective ways to prevent infection in infants and young children are to prevent HIV infection in women and to prevent unintended pregnancies among HIV-infected women. It is also possible, however, to prevent most cases of transmission from HIV-infected pregnant women to their infants. Antiretroviral prophylaxis in combination with other interventions such as elective caesarean section before onset of labour and rupture of membranes, and refraining from breastfeeding, have now almost entirely eliminated HIV infection in infants in the developed world, with transmission rates below 2%. In developing countries where breastfeeding is the norm, the risk of HIV transmission to the newborn child can be more than halved by short-course antiretroviral regimens, though this reduction is not sustained where feeding practices to reduce risk are not adopted.
To reduce the risk of postpartum transmission of HIV through breastfeeding, WHO currently recommends that when replacement feeding is acceptable, feasible, affordable, sustainable and safe, HIV-infected mothers avoid all breastfeeding. Otherwise, exclusive breastfeeding is recommended during the first months of life. To minimize the risk of postpartum transmission, breastfeeding should be discontinued as soon as is feasible, taking into account local circumstances, the individual woman’s situation and the risks posed by using replacement feeding, including infections other than HIV and malnutrition.
Although progress is now being made in the delivery of these low-cost and relatively simple interventions on a large scale in the most-affected countries, it has been slower than anticipated. Women must be encouraged and helped to attend antenatal care facilities, to accept counselling and testing, to return for test results and to adopt safer infant feeding practices, and must be given access to correctly administered antiretroviral drugs. Current challenges include achieving a rapid increase in acceptance of HIV testing and counselling, integrating prevention of infection in infants and young children into maternal and child health services, and extending the prevention of mother-to-child transmission to include HIV-related care, treatment and support for HIV-infected mothers, their infants and family.
Injecting drug use – reducing the harm
There may be as many as 2–3 million past and current injecting drug users living with HIV/AIDS worldwide. There are HIV epidemics associated with such drug use in more than 110 countries. In the absence of harm-reduction activities, HIV prevalence among injecting drug users can rise to 40% or more within one to two years of the introduction of the virus into their communities. HIV transmission through the sharing of non-sterile injection equipment is augmented by sexual transmission among injecting drug users, and between them and their sex partners.
Injecting drug users should have access to services that help reduce the related risks of drug use and HIV infection. Drug treatment programmes should be accessible to those who want to stop using drugs or, through substitution therapy, to stop injecting. Harm reduction primarily aims to help injecting drug users to avoid the negative health consequences of injecting and to improve their health and social status. Interventions include projects that try to ensure that those who continue injecting have access to clean injection paraphernalia. One evaluation carried out in 99 cities showed a reduction in the risk of HIV transmission of 19% per year in cities with such projects (with no concomitant increase in drug use) compared with an 8% increase in cities without them (55).
Preventing transmission during health care
Improper blood-transfusion practices are another important route of parenteral HIV transmission. Policies and procedures are needed to minimize the risk of transmission through blood transfusion, including the creation of a national blood service, use of low-risk donors, eliminating unnecessary transfusions, and systematic screening of blood for transfusion.
Universal precautions in health care settings prevent the transmission of HIV and other bloodborne pathogens, and therefore increased access to safer technologies is needed. A review of published studies has shown that unsafe injections play a minor but significant role in HIV transmission in sub-Saharan Africa (56). Irrespective of the exact contribution to the HIV/AIDS pandemic, unsafe injections are an unacceptable practice and efforts should be increased in all health care settings to reduce the exposure of patients and carers to bloodborne infections.
Testing and counselling
The vast majority of people living with HIV/AIDS in low-income countries are unaware that they are infected. Testing is an essential means of identifying these people and beginning treatment, and for preventing infection in mothers and infants. It is also a critical component of a comprehensive strategy to prevent sexual transmission. Studies have shown that people who test positive for HIV tend to reduce risk behaviours (57). Joint counselling and testing sessions with couples may increase condom use.
There is an urgent need to scale up access to counselling and testing, which should be offered as standard practice. An HIV test should always be performed with informed consent and appropriate confidentiality. Testing and counselling services must keep pace with the current new treatment and prevention opportunities. The onus will increase on national governments to provide high-quality testing and counselling services. Such services should become a routine part of health care, for example during attendance at antenatal clinics, or at tuberculosis and sexually transmitted infection diagnosis and treatment centres.