Schistosoma mansoni Mass Drug Administration Regimens and Their Effect on Morbidity among Schoolchildren over a 5-Year Period—Kenya, 2010–2015

Abstract

Abstract.Schistosomiasis control programs are designed to reduce morbidity by providing mass drug administration (MDA) of praziquantel to at-risk populations. We compared morbidity markers between two cohorts of Kenyan schoolchildren that initially had high prevalence of Schistosoma mansoni infections. One cohort (N = 416 at year 1) received four rounds of annual MDA in a community-wide treatment (CWT) strategy. The other cohort (N = 386 at year 1) received school-based treatment (SBT) every other year over the 4-year period. We measured infection with S. mansoni and soil-transmitted helminths (STH) as well as subtle morbidity markers at year 1, year 3, and year 5 and compared cohorts with mixed models after controlling for age and gender. At year 5, neither overall S. mansoni prevalence nor the prevalence of high infection–intensity S. mansoni infection was significantly reduced compared with baseline in either the CWT cohort (N = 277 remaining) or the SBT cohort (N = 235 remaining). Nevertheless, by year 5, children in both cohorts demonstrated significant decreases in wasting, ultrasound-detected organomegaly, and STH infection along with significantly improved pediatric quality-of-life scores compared with year 1. Stunting did not change over time, but children who were S. mansoni egg–positive at year 5 had significantly more stunting than children without schistosomiasis. The only significant difference between arms at year 5 was a lower prevalence of STH infections in the CWT group.

RETRACTED: Effect of Artemisia annua and Artemisia afra tea infusions on schistosomiasis in a large clinical trial

“…To our knowledge, there is no other drug in development against schistosomiasis. Recently annual mass drug administration of pediatrics with PZQ + albenzadol over a 5 yr period proved unsuccessful in reducing bilharzia prevalence (Sircar et al, 2018).…”

Changes in Morbidity, Physical Fitness, and Perceived Quality of Life among Schoolchildren following Four Years of Different Mass Drug Administration Strategies against Schistosoma mansoni Infection in Mwanza Region, Northwestern Tanzania

“…The same development in VO 2 max was reported in a parallel SCORE study in Kenya, where the authors suggest that this could be due to an increase in the prevalence of malaria and anemia in the first 2 years of the study. 19 However, in the present study, there was an improvement in Hb and reduction in anemia, and, therefore, we suggest that the decrease could be caused by an increase in the body weight of the children. Although the absolute maximal oxygen consumption normally rises with age, the VO 2 max (maximum oxygen uptake per kilo of body weight, mL/kg/ minutes) actually can decrease as children increase their body mass as a result of growth.…”

“…The present study was mirrored by another SCORE study in Kenya also along Lake Victoria and with a prevalence of ³ 25% S. mansoni among schoolchildren. 19 The Kenyan study used the same methodology and the same MDA approaches as the present study in Tanzania. In contrast with the present study, Kenyan schoolchildren were characterized by higher prevalence and intensity of infection, more anemia, and stunting as well as more pronounced hepatosplenic morbidity at the baseline.…”

Schistosomiasis Burden and Its Association With Lower Measles Vaccine Responses in School Children From Rural Cameroon

“…In Yoro, however, the situation is different with a prevalence of 19% for egg-positive stools in 2001 ( 3 ) to a current prevalence of 34.8% in schoolchildren of the site, the village appears to be a “dramatically persistent hotspot” of schistosomiasis ( 28 ). In fact, the sustained prevalence of schistosomiasis amid regular MDA is far from uncommon as recently observed in rural Kenya ( 29 ). This clearly suggests the inadequacy of current schemes of single annual MDA in endemic regions such as Yoro and warrants a more aggressive approach on such sites.…”