More than 1 million people in the United States are living with HIV, approximately 50,000 become infected with HIV each year, and more than 20,000 are dying each year. Worldwide, the story is even more tragic with more than 30 million people aged 15-49 years living with HIV and 2.5 million people becoming infected annually, the majority of them women. Although the number of HIV-related deaths is on the decline due to antiretroviral medications and other biomedical interventions, areas such as Africa have an increase in newly infected individuals, which is a cause of major concern. Widespread failure in vaccine and microbicide trials drives home the realization that we lack a strong enough understanding of the basic mechanisms of HIV transmission to successfully develop strategies to block viral acquisition.  

Despite the fact that HIV transmission rates are low for heterosexual transmission, there has been mounting data suggesting that certain biological risk factors exist that can increase the probability of HIV infection in both men and women. For example, one of the greatest risk factors associated with increased HIV transmission is the presence of sexually transmitted infections. In women, another possible risk factor associated with increased HIV transmission is progesterone-dominant hormonal states, as both laboratory studies and clinical trials have suggested that women utilizing the progesterone-only contraceptive Depo-Provera or women in the luteal phase of the menstrual cycle have an increased probability of infection. On the other hand, in men, whether or not an individual is circumcised has been illustrated to play a large role in HIV susceptibility as numerous clinical trials have shown a reduction in the risk of HIV infection by 50-60 percent in circumcised individuals. 

Importantly, there is still much that is unknown about HIV transmission and acquisition and a better understanding of HIV transmission events and associated risk factors is essential to interpret the results of ongoing clinical trials. More importantly, clinicians should consider these and similar evidence when treating individuals along with prescribing contraceptives to women who are at elevated HIV risk. This is especially true in Africa where STI prevalence is high amongst women and with over one-third of women being prescribed Depo-Provera. In this context, it is essential that women be informed of these risk factors so that they can better protect themselves from becoming infected. 

C2ST’s mission is to spread scientific knowledge and literacy from the labs to the general public. Initiatives such as the Global Health Symposium help to broadcast innovative research to those that need to know it, women and men, and C2ST is proud to be partnering with this important event. Over the past year we have ramped up our Health and Wellness programming to inform Chicagoans of the research that impacts their lives. Our programming has included events on cancer, Alzheimer’s disease, aging, the BRAIN initiative, just the brain, the Zika virus, and the effects of microbiomes in our guts and in our houses, among many others. And we are excited for the discussion at the symposium about these critical global health issues.