Co-infection with Schistosoma mansoni and Human Immunodeficiency Virus-1 (HIV-1) among residents of fishing villages of north-western Tanzania

Abstract

BackgroundCo-infection with S. mansoni and Human Immunodeficiency Virus-1 (HIV-1) has been described in sub-Saharan Africa. However, few community-based studies have been conducted to assess the association between the two diseases. The present study examined whether the infection with HIV-1 is associated with an altered susceptibility to S. mansoni infection by comparing the prevalence and intensity of S. mansoni infection among those infected and not infected with HIV-1. Any influence of HIV-1 associated immunodeficiency on the intensity of S. mansoni infection was also investigated.MethodsA cross-sectional study was conducted among 1,785 randomly selected adults (aged 21–55 years) in fishing villages of north-western Tanzania. Single stool samples were obtained and examined for S. mansoni eggs using the Kato Katz technique. Finger prick and venous blood samples were collected for HIV-1 screening and CD4+ cell quantification. Demographic information was collected by questionnaire.ResultsOf the 1,785 individuals from whom complete data were obtained, 854 (47.85%, 95% CI; 40.46 – 56.57) were infected with S. mansoni and had a mean intensity of 183.21(95% CI; 165.61-202.70) eggs per gram of faeces (epg). A total of 125 individuals (6.29%, 95% CI 3.59-11.04) were infected with HIV-1 and only 40% (n=50) of them were co-infected with S. mansoni. No differences in prevalence of S. mansoni infection or intensities of infection, as estimated by egg count (epg), were observed between HIV-1 sero-positive individuals and HIV-1 negative individuals. In generalized regression models (adjusted for sex, age, occupation, residence and level of education), being infected with HIV-1 did not increase the risk (APR=1.01, 95%; 0.83-1.21, P=0.93) or intensity (AOR = 0.84, 95% CI; 0.56-1.25, P = 0.33) of S. mansoni infection. Among individuals co-infected with HIV-1 and S. mansoni infection, the intensity of infection (epg) was not associated (P = 0.21) or correlated (P = 0.13) with CD4+ cell counts.ConclusionOur findings suggest that HIV-1 infection may not have a major effect on S. mansoni infection or on the excretion of eggs from the co-infected individuals. However, further studies are needed to understand the biological interaction between HIV-1 and S. mansoni in a large cohort of co-infected individuals.

Schistosomiasis and Human Immunodeficiency Virus in Men in Tanzania

“…Five of these were lakeside villages near Lake Victoria where S. mansoni is highly endemic, and four were inland villages where S. haematobium is highly endemic (Figure 1). 2,4,5 The study team visited each of the health posts for 1-3 days between April 2014 and February 2016. We recruited a community-based sample of healthy outpatient men aged 18-50 years in each study villages.…”

“…Several population-based studies in Tanzania and Uganda, which included both men and women, did not find an increased prevalence of HIV among those with S. mansoni infection. 5,6 Neither of these studies stratified data by gender, and both relied on schistosome egg excretion as the primary endpoint, which is less sensitive than schistosome antigen testing 7 and may be diminished in the setting of HIV infection. 8,9 Of note, in a subset of the Ugandan individuals who underwent urine schistosome antigen testing, the odds ratio (OR) for HIV infection was 1.5 with a P value of 0.19, suggesting that the study may have lacked sufficient power to detect a smaller increased risk.…”

Selected aspects of helminth infections Schistosoma sp., Ascaris lumbricoides, Strongyloides stercoralis in individuals diagnosed with human immunodeficiency virus (HIV) infection

“…Obszary o wysokiej endemii obserwuje się w Etiopii, Nigerii, RPA, Zimbabwe czy Zambii. Odsetek zarażonych osób przekracza 50%, a może być znacznie wyższy na obszarach takich jak Mozambik czy Madagaskar (10,45,46). Częstość zakażeń HIV w tych krajach szacuje się od 15% do 28%.…”

“…W przebiegu koinfekcji HIV i S. mansoni wydaje się, że istotne znaczenie ma kolejność zakażenia/zarażenia oraz wiek pacjenta, jednakże uzyskiwane wyniki nie są jednoznaczne (47,48,49). U dzieci, najczęściej pierwszym zakażeniem jest HIV (np.…”

“…U pacjentów pierwotnie zarażonych przywrami, a następnie zakażonych HIV, obserwuje się mniej wydalanych jaj pasożytów (45,52). Uzyskane wyniki sugerują, że dla prawidłowego przebiegu cyklu życiowego przywry (zachowania płodności pasożyta), konieczne jest zachowanie aktywności układu immunologicznego, wyrażonej prawidłową liczbą LT CD4.…”