Authors

SA Kayuni¹; P Makaula¹; G Namacha¹; D Lally¹; D Kapira¹; P Chammudzi¹; S Jones²; S Rollason²; AL Reed³; J Archer²; L Cunningham²; A Juhasz²; EJ Lacourse²; J Musaya¹; JR Stothard²;  ¹ Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Malawi;  ² Liverpool School of Tropical Medicine, UK;  ³ Lancaster University, UK

Discussion

Introduction

The discovery of novel Schistosoma haematobium hybrids co-infecting school-aged children in Nsanje and Mangochi districts in Malawi exposes critical knowledge gaps in the control of schistosomiasis. Hybridization in urogenital schistosomiasis (HUGS) is a longitudinal population study aimed at investigating transmission biology and epidemiological impact of Schistosoma haematobium-hybrids in Malawi.

A baseline survey was conducted to determine the prevalence of urogenital schistosomiasis in two communities of Nsanje and Mangochi districts and if the proportion of S. haematobium hybrid co-infections are uniform across the communities.

Methods

We conducted a baseline survey in July 2022. Households were selected randomly in 8 villages around Mthawira Primary school in Nsanje district and 3 villages around Samama Primary school in Mangochi district to attain a sample size of 2,400. Individual questionnaires were administered to enrolled participants, eliciting information on their health, education, socioeconomic status, water contact and available livestock.

Urine samples were collected to tests for schistosomiasis using point-of-care CCA and urine filtration. All positive individuals were treated with Praziquantel (PZQ), according to the Ministry of Health treatment guidelines in addition, all people in the 2 study communities were offered PZQ as part of preventive chemotherapy recommended by WHO.

Preliminary results

348 participants (32.7%) had S. haematobium eggs in their urine samples in Nsanje district, with 617 (49.8%) in Mangochi district. 8.2% participants had high infection intensity (50+ S. haematobium eggs eggs) in Nsanje, while 16.4% were in Mangochi.

The high infection intensity in Nsanje was observed more in older children and adults, 7-15 and 26-36 years’ age-group, as compared to younger children in Mangochi, thus 1-6 and 7-15 years’ age-groups. 1.0% participants had positive POC-CCA in Nsanje indicative of possible intestinal S. mansoni co-infection, and 12.4% in Mangochi district.

Further data and molecular analyses to determine the level of the hybrid infections in the survey population are currently in progress and preliminary findings to be presented subsequently.

Conclusions

Preliminary results indicate significant burden of urogenital S. haematobium infections among survey participants in the 2 districts.

Further studies include follow-up surveys of hybrid co-infections in the study population and assessment for increased morbidity from genital schistosomiasis in hybrid co-infected participants in the study districts.