A recent study was done in Chad exploring the possibility that Herpes Simplex Virus 2 (HSV-2) is a significant co-factor for the transmission of HIV-1 in different regions of the country. The researchers took blood samples from adults in most of the regions of the country (2 regions were inaccessible at the time of the study) and did serology tests on dried blood samples. Each sample that was randomly selected for serology testing was tested for HIV-1 and HSV-2. The number of samples chosen for testing from each region was proportional to the population in the region, so as to acquire meaningful geographic disease rates.
The results from HIV-1 were fairly constant throughout the country while there were hot spots with high rates of HSV-2. Two of these hot spots included areas that harbor many displaced individuals from civil conflicts that are a known high-risk group for HSV-2 and other STIs. The data does not prove that HSV-2 is a significant biological co-factor for HIV-1, however the article suggests that transmission of the two diseases, that together make a devastating diagnosis, is inherently linked and hot spots, such as those discovered in southern Chad, are in serious need of health intervention.