Molecular detection of trematodes of Schistosoma haematobium group in domestic ruminants in the Republic of Niger: challenges of schistosomiasis control

Abstract

Schistosomiasis remains a major public health problem in Niger, where control programs rely primarily on the mass administration of drugs to human populations. Although Schistosoma (S.) haematobium is traditionally associated with the human urogenital form, recent findings suggest that domestic ruminants could serve as natural reservoirs, thus complicating disease elimination. This study aims to document, for the first time, the potential presence of this parasite group in livestock in Niger. This cross-sectional study was conducted in the Dosso region, including the communes of Gaya and Dosso. A total of 84 urine samples were collected from ruminants, either by bladder incision at the slaughterhouse ( n = 57) or directly from live animals ( n = 27). Identification was performed by microscopy for egg detection, followed by molecular detection including standard PCR (targeting the ITS2 and COX1 genes) and Dra1 qPCR specific to the S. haematobium group. The overall prevalence identified by microscopy was 30.95% (26/84; 95% CI: 21.03–40.87). Of the 26 microscopically positive samples, 84.61% (22/26; 95% CI: 70.74–98.48) were detected by Dra1 qPCR. Molecular PCR detected the genus Schistosoma ( ITS2 ) in 26.92% (95% CI: 9.87–43.97) and S. haematobium group (COX1) in 23.08% (95% CI: 6.88–39.27) of tested samples. This study suggests the potential circulation of S. haematobium group in domestic ruminants in Niger, suggesting that livestock could constitute a significant local reservoir for urinary schistosomiasis. These results highlight the need to adopt a One Health approach integrating animal health into control strategies to effectively interrupt human transmission.