Morbidity associated with Schistosoma mansoni infection in north-eastern Democratic Republic of the Congo

Abstract

Background Reducing morbidity is the main target of schistosomiasis control efforts, yet only rarely do control programmes assess morbidity linked to Schistosoma sp. infection. In the Democratic Republic of Congo (DRC), and particularly in north-eastern Ituri Province, little is known about morbidity associated with Schistosoma mansoni infection. For this reason, we aimed to assess intestinal and hepatosplenic morbidity associated with S. mansoni infection in Ituri Province. Methods/Principal findings In 2017, we conducted a cross-sectional study in 13 villages in Ituri Province, DRC. S. mansoni infection was assessed with a Kato-Katz stool test (2 smears) and a point-of-care circulating cathodic antigen (POC-CCA) urine test. A questionnaire was used to obtain demographic data and information about experienced intestinal morbidity. Each participant underwent an abdominal ultrasonography examination to diagnose hepatosplenic morbidity. Of the 586 study participants, 76.6% tested positive for S. mansoni. Intestinal morbidity reported in the two preceding weeks was very frequent, and included abdominal pain (52.7%), diarrhoea (23.4%) and blood in the stool (21.5%). Hepatosplenic morbidity consisted of abnormal liver parenchyma patterns (42.8%), hepatomegaly (26.5%) and splenomegaly (25.3%). Liver pathology (adjusted odds ratio [aOR] 1.20, 95% confidence interval [CI] 1.06–1.37, p = 0.005) was positively and significantly associated with S. mansoni infection. Hepatomegaly (aOR 1.52, 95% CI 0.99–2.32, p = 0.053) and splenomegaly (aOR 1.12, 95% CI 0.73–1.72, p = 0.619) were positively but not significantly associated with S. mansoni infection at the individual level. At the village level, S. mansoni prevalence was positively associated with the prevalence of hepatomegaly and splenomegaly. High-intensity S. mansoni infections were associated with diarrhoea, blood in the stool, hepatomegaly, splenomegaly, and liver parenchyma (C, D, E and F pathology patterns). Four study participants were diagnosed with ascites and five reported hematemesis. Conclusions/Significance Our study documents a high burden of intestinal and hepatosplenic morbidity associated with S. mansoni infection status in Ituri Province. The findings call for targeted interventions to address both S. mansoni infection and related morbidity.

Schistosoma mansoni Infections and Morbidities Among School Children in Hotspot Areas of Jimma Town, Southwest Ethiopia: A Cross-Sectional Study

“… 11 , 37 , 38 The clinical manifestations are often chronic forms in endemic regions which may include diarrhea, blood in stool, colicky pain, general malaise, anemia, stunting, hepatosplenic pathogenesis, portal hypertension, and other complications. 11 , 12 , 16 The majority of the schoolchildren who participated in this study had reported at least one of these symptoms during the survey. In this study, S. mansoni infection was significantly associated with blood in stool in the last two weeks and a feeling of general malaise during the survey.…”

“…Studies conducted elsewhere also reported a positive association between S. mansoni infections and blood in stool. 16 , 19 Blood loss with stool may lead the infected children to iron deficiency anemia. The schoolchildren feeling general malaise may also experience school absenteeism, low school performance, and concomitant cognitive impairment.…”

“…5 Infection may result in malaise, anemia, intestinal and urogenital bleeding, and portal hypertension. [13][14][15][16] Hence, the children may fall ill with possible subsequent cognitive impairment, undernutrition, and growth retardation. 17 Moreover, due to morbidities associated with schistosomiasis, schoolchildren may not pay 2 Environmental Health Insights attention in the class and/or result in school absenteeism.…”

A randomized, controlled Phase 1b trial of the Sm-TSP-2 Vaccine for intestinal schistosomiasis in healthy Brazilian adults living in an endemic area

“…Several anti-schistosomal vaccines are currently in preclinical or clinical development [11,12]. Recombinant S. mansoni Tetraspanin-2 (Sm-TSP-2) formulated on Alhydrogel, an aluminum hydroxide salt adjuvant, is being developed to prevent heavy infections with S. mansoni, given that morbidity is related to infection intensity [13]. Schistosomes express a family of integral transmembrane proteins that locate to the epithelial syncytium forming the body wall, or tegument, of several stages of the schistosome life cycle, and are considered essential to the formation, maintenance, and turnover of the transient outer surface of this helminth [14,15].…”