Extant interspecific hybridization among trematodes within the Schistosoma haematobium species complex in Nigeria.

BACKGROUND: Natural interspecific hybridization between the human parasite (Schistosoma haematobium [Sh]) and bovine parasites (Schistosoma bovis [Sb], Schistosoma curassoni [Sc]) is increasingly reported in Africa. We developed a multi-locus PCR DNA-Seq strategy that amplifies two unlinked nuclear (transITS, BF) and two linked organellar genome markers (CO1, ND5) to genotype S. haematobium eggs collected from infected people in Ile Oluji/Oke Igbo, Ondo State (an agrarian community) and Kachi, Jigawa State (a pastoral community) in Southwestern and Northern Nigeria, respectively. PRINCIPAL FINDINGS: Out of a total of 219 urine samples collected, 57 were positive for schistosomes. All patients from Jigawa state possessed an Sh mitochondrial genome and were infected with a genetic profile consistent with an Sh x Sb hybrid based on sequences obtained at CO1, ND5, transITS and BF nuclear markers. Whereas samples collected from Ondo state were more varied. Mitonuclear discordance was observed in all 17 patients, worms possessed an Sb mitochondrial genome but one of four different genetic profiles at the nuclear markers, either admixed (heterozygous between Sh x Sc or Sh x Sb) at both markers (n = 10), Sh at BF and admixed at transITS (Sh x Sc) (n = 5), admixed (Sh x Sc) at BF and homozygous Sc at transITS (n = 1) or homozygous Sh at BF and homozygous Sc at transITS (n = 1). SIGNIFICANCE: Previous work suggested that zoonotic transmission of S. bovis in pastoral communities, where humans and animals share a common water source, is a driving factor facilitating interspecific hybridization. However, our data showed that all samples were hybrids, with greater diversity identified in Southwestern Nigeria, a non-pastoral site. Further, one patient possessed an S. bovis mitochondrial genome but was homozygous for S. haematobium at BF and homozygous for S. curassoni at transITS supporting at least two separate backcrosses in its origin, suggesting that interspecific hybridization may be an ongoing process.

Urinary schistosomiasis and anemia among school-aged children from southwestern Nigeria.

Schistosomiasis and anemia, are one of the leading global public health problem among children between age 5 and 14 years in marginalized settings. In this study, we provide prevalence and intensity data for both conditions in three southwestern states of Nigeria, where such are lacking. Epidemiological assessment involving parasitological analysis of urine and blood samples was conducted among 1783 consenting school-aged children in Ondo, Osun, Ekiti States of Nigeria. Participants' age and sex data were obtained using field forms, and statistical analysis was performed in R software with a significance level of 95%. An overall prevalence of 26.8% and 29.5% was recorded for urinary schistosomiasis and anemia, respectively. Prevalence varied by location with (40.3% and 29.8%) in Ondo (34.4% and 37.5%) in Osun and (13.4% and 20.9%) in Ekiti for urinary schistosomiasis and anemia, respectively (p=0.00). Schistosoma infections were found among males (28.7%, p=0.05) and children between the age 9-11 years (30.0%, p=0.01). About 36% of children with anemia was also infected with schistosomiasis. Children who were positive for schistosomiasis (OR:1.51; 95% CI: 1.19, 1.93; p=0.001) and between the age category 15-16 years, (OR:1.86; 95% CI: 1.12, 3.09; p<0.05) were twice likely to become anemic. Our findings have shown that children infected with schistosomiasis are twice likely to become anemic than those without infection. It is important to complement ongoing MDA programmes targeted at schistosomiasis with nutrition intervention programs for example micronutrient supplementation for better impact and cost-effectiveness.

Multisectoral Perspectives on Global Warming and Vector-borne Diseases: a Focus on Southern Europe.

Purpose of Review: The climate change (CC) or global warming (GW) modifies environment that favors vectors' abundance, growth, and reproduction, and consequently, the rate of development of pathogens within the vectors. This review highlights the threats of GW-induced vector-borne diseases (VBDs) in Southern Europe (SE) and the need for mitigation efforts to prevent potential global health catastrophe. Recent Findings: Reports showed astronomical surges in the incidences of CC-induced VBDs in the SE. The recently (2022) reported first cases of African swine fever in Northern Italy and West Nile fever in SE are linked to the CC-modified environmental conditions that support vectors and pathogens' growth and development, and disease transmission. Summary: VBDs endemic to the tropics are increasingly becoming a major health challenge in the SE, a temperate region, due to the favorable environmental conditions caused by CC/GW that support vectors and pathogens' biology in the previously non-endemic temperate regions.