The years leading up to violent conflict may be a time of particularly high HIV transmission, according to results of a study that looked at HIV incidence in sub-Saharan Africa and was recently published in PLOS One.

The Brown University analysis reports that the rate of new infections rises significantly in the five years leading up to a conflict.

“[The findings] imply that there is something going on in social, political, and health care environments in those years that are conducive to HIV spread,” lead author Brady Bennett explained in a prepared statement.

The study tracked HIV incidence in 36 sub-Saharan countries from 1990 through 2012 and correlated them with periods of conflict and peace in each country. The research team was therefore able to calculate how the incidence rose and fell in each country in relation to violence, while controlling for other factors such as economic development, refugee influx, and the year of the region’s broader epidemic, which generally peaked in 1996.

Compared to times of peace, the analysis showed, HIV incidence increased by 2.1 infections per 1000 people a year in the five years before a conflict where at least 25 people died as a result of fighting. The researchers also found that during conflict, the incidence rate declined by 0.07 infections per 1000 people, compared to times of peace. The study defines conflict as violence that claims at least 25 battle-related deaths. Researchers found that as conflicts became more bloody, HIV incidence tended to drift down a bit more.

Each country had a different HIV trajectory through war and peace (some had no conflict at all), but countries such as Burundi, Eritrea, Nigeria, and Uganda all endured their highest HIV incidence rates in periods before conflict and lower rates during conflict.

The findings suggest that waiting to intervene until conflict is already underway may miss a major opportunity to prevent new infections, the researchers noted.


  1. Bennett BW, Marshall BDL, Gjelsvik A, et al. HIV incidence prior to, during, and after violent conflict in 36 sub-Saharan African nations, 1990-2012: An ecological study. PLOS ONE, 2015; 10 (11): e0142343 DOI:10.1371/journal.pone.0142343

This article originally appeared on Infectious Disease Advisor