Time to take a longer view of transmission dynamics

Stefan Baral
Danya-Zee Pedra, SHARE staff

Today’s plenary session on Breaking barriers of inequity in the HIV response started with a powerful message from Dr Stefan Baral of the Johns Hopkins School of Public Health in his presentation on the epidemiology and vulnerability of missing and indigenous populations: “HIV does not discriminate, but in the absence of services, we’re going to continue to see these epidemics.”

A significant case in point are female sex workers (FSWs). A recently updated Call to Action which examined the burden of HIV among sex workers around the world clearly shows that the epidemic among FSWs in southern Africa is profound, and is driven by both biological and structural realities.  


An estimated one-third of FSWs are living with HIV across the region, but they are not considered to be relevant because they represent a relatively small percentage of overall HIV prevalence. Dr Baral challenged this perspective, comparing data on new infections attributable to the unmet treatment needs of FSWs with sero-discordant partnerships among the wider population. Over a one-year period, only about 8% of new HIV infections are due to the unmet treatment needs of FSWs. However, this increases dramatically to 40% over a 20-year period – demonstrating that reaching FSWs with HIV services is critical. 

Making another fundamental point about how we should be responding to HIV if we are to effectively reduce incidence, Dr Baral explained that, “in the context of the many really high-order prevention programs like pre-exposure prophylaxis and the vast numbers of adolescent girls and young women that have no HIV risk across southern Africa, it’s important to understand whose risks are real, and who really needs these intense interventions.” He further pointed out that in terms of gay men and other men who have sex with men and transgender women across the region, we need to move past preconceived notions of the epidemiology of HIV, assess people’s risks in an open and competent way, and address them appropriately, no matter what the geography or social context.

Similarly, although raised in the context of indigenous communities in Latin America, the issue of systematic barriers to engagement in national health programs, and how this results in sustained and expanding epidemics, needs to be tackled. Dr Baral remarked that the case of FSWs in southern Africa clearly demonstrates how, 40 years into this pandemic, we need to take a longer view of transmission dynamics in terms of understanding and informing responses for meaningful scale-up of prevention and treatment services.

Finally, Dr Baral highlighted that we need to understand that HIV is not Zika. There is not a place in the world where risks are evenly distributed in the population. To great applause, he stressed that we need to start moving away from the term “general population” – because it is fundamentally important to understand who and why people are living with HIV, irrespective of where they are, to allow us to serve them better and to provide more effective programming.

Want to hear more? Watch the plenary video here.

Stefan Baral