Concentrated and linked epidemics of both HSV-2 and HIV-1/HIV-2 infections in Senegal: public health impacts of the spread of HIV.

The objective of this article is to report seroprevalences on HIV and herpes simplex virus 2 (HSV-2) in female sex workers (FSW) and in two sentinel populations of pregnant women living in Senegal. Serosurveys of HIV and HSV-2 were conducted in two unselected sentinel populations from Dakar, Senegal, and its provinces, including in 2003 only pregnant women and 2006 pregnant women and FSW. The population study involved 888 pregnant women and 604 FSW. In pregnant women, HIV and HSV-2 seroprevalences were, respectively, 1.01% and 15.65%. There was no association between HSV-2 and HIV infection, whatever the age. In contrast, the seroprevalence of HIV infection in the group of FSW was high, reaching 22.9% in women over 30 years old. FSW above 20 years of age harboured much higher HSV-2 seroprevalences that those found in pregnant women of similar age groups. In FSW, strong associations between HSV-2 and age, and among HSV-2 and HIV-1 as well HIV-2, were evidenced. In conclusion, HIV epidemic remains concentrated in high-risk groups of the Senegalese population, such as the FSW population in which the seroprevalence of HSV-2 infection is very high. Intervention against STI including HSV-2 is urgently needed to prevent the spreading of HIV epidemic.

Full-length genome sequencing of HIV type 1 group O viruses isolated from a heterosexual transmission cluster in Senegal.

In a polygamous marriage in Senegal, the husband and his two spouses were infected with HIV-1 group O. This study provides new full-length genome sequences for the two spouses (99SE-MP1299 and 99SE-MP1300) and the 3'-end LTR-tat fragment (6084 bp) for the husband (98SE-42HALD). Phylogenetic tree and diversity plot analysis revealed that the new viruses belong to HIV-1 group O and that they are closely related to each other in a cluster around ANT-70. The intrafamilial transmission occurred at most 6 years ago. The interpatient variability was highest in the envelope region, and in some regions of the envelope the strains from the two spouses do not cluster together anymore. The source of infection was in Cameroon and confirms a slow but continuous spread of HIV-1 group O viruses.