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

PLoS Negl Trop Dis. 2021 Dec 2;15(12):e0009375. doi: 10.1371/journal.pntd.0009375. eCollection 2021 Dec.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Animals
  • Anthelmintics / therapeutic use
  • Antibodies, Helminth / blood
  • Child
  • Cross-Sectional Studies
  • Democratic Republic of the Congo / epidemiology
  • Female
  • Humans
  • Male
  • Middle Aged
  • Morbidity
  • Prevalence
  • Rural Population / statistics & numerical data
  • Schistosoma mansoni / immunology
  • Schistosoma mansoni / pathogenicity*
  • Schistosomiasis mansoni / complications*
  • Schistosomiasis mansoni / drug therapy
  • Schistosomiasis mansoni / epidemiology*
  • Schistosomiasis mansoni / immunology
  • Splenomegaly / epidemiology
  • Young Adult

Substances

  • Anthelmintics
  • Antibodies, Helminth

Grants and funding

The study was funded by private funds (Poverty Fund, Switzerland), to P.R.H. The funders had no role in study design, data collection and data analysis, decision to publish, or preparation of the manuscript.