How can HIV transmission be prevented?

Hiv can be transmitted in three main ways:

 

 

• Sexual transmission
• Transmission through blood  
• Mother-to-child transmission

 

For each route of transmission there are things that an individual can do to reduce or eliminate risk. There are also interventions that have been proven to work at the community, local and national level.1

 

 

 

Wherever there is HIV, all three routes of transmission will take place. However the number of infections resulting from each route will vary greatly between countries and population groups. The share of resources allocated to each area should reflect the nature of the local epidemic - for example, if most infections occur among men who have sex with men then this group should be a primary target for prevention efforts.

 

 "Knowing your epidemic in a particular region or country is the first, essential step in identifying, selecting and funding the most appropriate and effective HIV prevention measures for that country or region." - UNAIDS guidelines for HIV prevention 2

 

HIV prevention should be comprehensive, making use of all approaches known to be effective rather than just implementing one or a few select actions in isolation. Successful HIV prevention programmes not only give information, but also build skills and provide access to essential commodities such as condoms or sterile injecting equipment. It should be remembered that many people don’t fit into only one “risk category”. For example, injecting drug users need access to condoms and safer sex counselling as well as support to reduce the risk of transmission through blood.

 

What are the obstacles?

 

Despite the evidence that they do not encourage drug use, some authorities still refuse to support needle exchanges and other programmes to help injecting drug users. Restrictions on pharmacies selling syringes without prescriptions, and on possession of drug paraphernalia, can also hamper HIV prevention programmes by making it harder for drug users to avoid sharing equipment.Many resource-poor countries lack facilities for rigorously screening blood supplies.31 In addition a lot of countries have difficulty recruiting enough donors, and so have to resort to importing blood or paying their citizens to donate, which is not the best way to ensure safety. In much of the world the safety of medical procedures in general is compromised by lack of resources, and this may put both patients and staff at greater risk of HIV infection. Find out more about preventing HIV transmission through blood.

Mother-to-child transmission

What works?


HIV can be transmitted from a mother to her baby during pregnancy, labour and delivery, and later through breastfeeding. The first step towards reducing the number of babies infected in this way is to prevent HIV infection in women, and to prevent unwanted pregnancies.



There are a number of things that can be done to help a pregnant woman with HIV to avoid passing her infection to her child. A course of antiretroviral drugs given to her during pregnancy and labour as well as to her newborn baby can greatly reduce the chances of the child becoming infected. Although the most effective treatment involves a combination of drugs taken over a long period, even a single dose of treatment can cut the transmission rate by half.32



A caesarean section is an operation to deliver a baby through its mother’s abdominal wall, which reduces the baby’s exposure to its mother’s body fluids. This procedure lowers the risk of HIV transmission, but is likely to be recommended only if the mother has a high level of HIV in her blood, and if the benefit to her baby outweighs the risk of the intervention.33 34



Weighing risks against benefits is also critical when selecting the best feeding option. The World Health Organisation advises mothers with HIV not to breastfeed whenever the use of replacements is acceptable, feasible, affordable, sustainable and safe. However, if safe water is not available then the risk of life-threatening conditions from replacement feeding may be greater than the risk from breastfeeding. An HIV positive mother should be counselled on the risks and benefits of different infant feeding options and should be helped to select the most suitable option for her situation.35

What are the obstacles?

In much of the world a lack of drugs and medical facilities limits what can be done to prevent mother-to-child transmission of HIV. Antiretroviral drugs are not widely available in many resource-poor countries, caesarean section is often impractical, and many women lack the resources needed to avoid breastfeeding their babies.
HIV-related stigma is another obstacle to preventing mother-to-child transmission. Some women are afraid to attend clinics that distribute antiretroviral drugs, or to feed their babies formula, in case by doing so they reveal their HIV status.
Find out more about preventing mother-to-child transmission (PMTCT) and why PMTCT programmes are failing to reach most women in need.