Evaluating the potential impact of mass praziquantel administration for HIV prevention in Schistosoma haematobium high-risk communities

Abstract

Genital infection with Schistosoma haematobium is prevalent in sub-Saharan Africa. Epidemiological studies have observed that genital schistosomiasis is associated with an increased odd of HIV infection among women. We used mathematical modeling to explore the potential impact of mass preventive chemotherapy against schistosomiasis on HIV transmission in three sub-Saharan Africa countries: Angola, Kenya, and Zambia. We developed a model of female genital schistosomiasis (FGS) and HIV transmission dynamics, fitting it to data of HIV and S. haematobium prevalences as well as co-infection. We simulated targeted mass drug administration (MDA) with praziquantel to school-age children and mass treatment of the entire community. We estimated that, in S. haematobium high-risk communities, targeted annual treatment of school-age children could reduce HIV prevalence by 20% (95% CI: 12%–31%) in Angola, 16% (95% CI: 10%–32%) in Kenya, and 6% (95% CI: 3%–18%) in Zambia after the first twenty years of intervention; and would reduce HIV incidence by 15% (95% CI: 13–32) in Angola, 22% (95% CI: 18–42) in Kenya, and 9% (95% CI: 3–22) in Zambia. Extending the intervention to adults could reduce HIV prevalence by an additional 2.2% (95% CI: 0.2%–12.0%) in Angola, 1.8% (95% CI: 0.1%–5.2%) in Kenya, and 0.3% (95% CI: 0.1%–2.1%) in Zambia; and would reduce HIV incidence by an additional 1.8% (95% CI: 0.0–14.4) in Angola, 6.1% (95% CI: 0.5–12.6) in Kenya, and 0.8% (95% CI: 0.0–2.7) in Zambia. We showed that the exacerbation of HIV transmission due to FGS and the probability of developing FGS as a result of childhood infection with S. haematobium, were the most important factors in determining the effectiveness of praziquantel MDA for reducing HIV transmission. Praziquantel MDA may be an innovative measure for reducing schistosomiasis and HIV transmissionin sub-Saharan Africa, the effectiveness of which varies with HIV prevalence.

Evaluating long-term effectiveness of sleeping sickness control measures in Guinea

“…To estimate posterior distributions for the unknown epidemiological parameters—probability of tsetse bite on humans ( β VH ), transmission probability from tsetse to humans ( β H ), treatment seeking rate of stage II patients ( ζ ) and transmission probability from tsetse to NHA ( β L )—we used a Bayesian melding method [ 23 , 24 ] to calibrate the model to prevalence data for stage I and stage II HAT cases in Boffa East Mainland in 2008, as well as Trypanosomiasis prevalence among tsetse and the NHA reservoir [ 12 , 21 ]. Given that there was no active screening or vector control in Boffa between 2000 and 2008, we assumed an equilibrium prevalence prior to 2008.…”

Knowledge and awareness of genital involvement and reproductive health consequences of urogenital schistosomiasis in endemic communities in Ghana: a cross-sectional study

“…Luckily, urogenital schistosomiasis is a treatable condition. Studies have shown genital lesions to regress after treatment with praziquantel [ 2 , 14 , 15 ]. Some protection against sexually transmitted infections (STIs) and HIV infection may also be achieved when infected individuals are treated (untreated urogenital schistosomiasis may result in various tissue lesions that can be easily infected by other bacteria and/or viruses).…”

Something Old, Something New: is Praziquantel Enough for Schistosomiasis Control?

“…Other operational research needs for praziquantel include evaluation of the efficiency and safety when used in conjunction with drugs for other neglected tropical diseases in integrated MDAs. In addition, with the recognition that schistosomiasis may increase risk of infection with malaria or HIV [17,18], the benefits of treating schistosomiasis on reducing the transmission or manifestations of these and other coinfecting agents should be considered.…”