The International AIDS Vaccine Initiative (IAVI) has a fantastic fellowship program, and two of their fellows have been researching at the Desmond Tutu HIV Foundation. Separately, they have researched why people refuse HIV treatment and how drugs that prevent HIV transmission can also be used to prevent hepatitis B.
Sicily Mburu, an IAVI fellow at DTHF, worked as a medical doctor in Kenya before joining the POWER study at the Desmond Tutu HIV Foundation. Mburu worked on a sub-study within the Power study to investigate the perceived and actual HIV risk of adolescent girls and young women who decline PrEP. Short for Pre-Exposure Prophylaxis, PrEP is a daily oral pill that gives the user protection against HIV infection. If their perception of their risk of infection is different to their actual risk, then this information can direct future intervention campaigns. The sub-study recruitment site is the community-based mobile clinic at the Tutu Teen Truck. This is a DTHF truck which doubles as a clinic that drives straight into communities where healthcare access is limited.
In Sub Saharan Africa, 75% of the people living with HIV are young women between the ages of 15-24. This is an exceptionally high burden. The POWER study aims to make PrEP available for 1000 participants between 16-25 years old to help reduce new incidences of HIV. The profile for a woman at-risk is HIV negative, PrEP naive and sexually active. The recruitment , data collection and analysis is ongoing.
Abdul Ibrahim, an IAVI fellow at the Desmond Tutu HIV Foundation (DTHF), helped analyse data from a cohort of HIV-negative adolescents in South Africa. DTHF is part of the Plus Pills study which assesses whether certain drugs can prevent HIV. PreExposure Prophylaxis (PrEP) is a drug taken by HIV negative people to prevent HIV infection. Ibrahim is interested in how this drug breaks the chain of HIV transmission, and hopes that PrEP can do something similar for another chronic virus: Hepatitis B (HBV).
HBV is a virus that infects the liver and can be potentially life-threatening. Fortunately, there are preventative tools that protect from the infection, including a vaccination. Additionally, HBV can be acute; only If the virus is in the body more than four months it is considered a chronic condition. 2.5 million people are chronically infected with HBV in South Africa, which is challenging with the additional HIV burden.
A recent study suggested that is okay for an individual to take PrEP to prevent HBV as well as HIV. If a patient gets either HIV or HBV, then PrEP is no longer suitable. An HIV or HBV infected person should stop taking PrEP and start taking antiretroviral therapy.
Ibrahim’s research examined a cohort of adolescents in locations in South Africa. It was found that 82% were at risk of HBV infection. This means that they had no HBV immunity, whether from vaccination or from recovering from acute HBV. However, some of these adolescents were vaccinated at birth, so their loss of immunity indicates that a booster vaccination is required. Ibrahim concluded that their data recommended a booster dose of the HBV for this cohort.
It was impossible to know which of the cohort had received vaccinations because of poor record keeping and no central database. HBV infection in HIV uninfected adolescents is declining, though a substantial amount of these individuals are at risk of contracting the virus. A booster shot is enough for providing immunisation, even in people who have never been vaccinated before. Therefore, PrEP could be greatly beneficial for these at-risk individuals.
Image 1: Elzette Rousseau, Sicily Mburu, Robin Julies, all partnered for the POWER study | Caroline Reid
Image 2: Abdul Ibrahim
Written by Caroline Reid