The interplay of within-host and between-host dynamics regulates HIV-1 epidemiological outcomes

HIV-1 has nine main subtypes that persist in the infected populations. However, the overall diversity of HIV-1 is much larger thanks to recombination amongst these original subtypes. Recombination has led to over a hundred circulating recombinant forms (CRFS), which may become more prevalent than the two parent strains. We analysed sequences taken from the Los Alamos National Lab HIV database and found different trends for various CRFS depending on the country of origin. However, what drives these differences, is it within-host or between-host dynamics? To investigate, we developed a mathematical model of HIV-1 viral recombination that incorporated within-host dynamics (viral competition and recombination) and between-host dynamics (transmission rates and emergence time in the population) to understand which part of the dynamics matters more. We apply this method to three scenarios regarding CRF emergence in Brazil and China, showing that our model can capture the three scenarios. Given the model assumptions, we also show that withinhost dynamics are an early driver in the emergence of CRFs. However, between-host events will determine the level at which a CRF may be expressed in the population.

The interplay of within-host and between-host dynamics regulates HIV-1 epidemiological outcomes

Monday, July 14 at 6:00pm

Macauley Locke

"The interplay of within-host and between-host dynamics regulates HIV-1 epidemiological outcomes"

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