An estimated 6 million individuals are co-infected with HIV and schistosomiasis. This thesis seeks to add to the comprehension of the epidemiology of HIV and schistosome co-infections in Tanzania,... Show moreAn estimated 6 million individuals are co-infected with HIV and schistosomiasis. This thesis seeks to add to the comprehension of the epidemiology of HIV and schistosome co-infections in Tanzania, by Lake Victoria. It first evaluates Tanzania’s progress regarding HIV care and defines the study population and the challenges it faces in the fight against co-infections. It then explores the impact of Schistosoma infection on HIV outcomes and transmission. One of the main findings is that people who were infected with Schistosoma when they also acquired HIV infection, on average survive longer and have slower decline in CD4 counts than those who were not infected with Schistosoma in the first place. This thesis also shows that individuals with HIV and Schistosoma spp. co-infections have lower viral loads than those with HIV alone, when accounting for time infected with HIV, and estimates the first hazard rate of HIV transmission from co-infected partners. Finally, this thesis explores the impact of HIV infection on the detection of Schistosoma in co-infected people and concludes that co-infected individuals and women are less likely to excrete parasite eggs. Both local and systemic interactions are discussed in light of those results. Show less