Geospatial Mapping and Seasonal Profiling of Urinary Schistosomiasis in Ase-Niger River Settlements: A Data-Driven Population-Base Study in Delta State, Nigeria.

OBJECTIVES: This study is aimed to determine the geospatial, seasonal, age and gender prevalence and intensity of UgS; and to establish disease maps in the Ase-Niger River communities for effective drug administration. STUDY DESIGN: This study employed a 24 months longitudinal study design for parasitological investigations in 11 riparian communities of the Ase-Niger River basin, taking into cognizance their GPS locations imported into QGIS software for schistosomiasis mapping. METHODS: A total of 7,219 urine samples with WHO structured questionnaires were retrieved and subjected to parasitological evaluation using swinnex urine filtration techniques. RESULTS: An overall prevalence of 48.10% was established. Geospatially, prevalence ranges from 34.27% (Ivrogbo) to 52.29% (Ase) with seasonal significant difference (p < 0.05) accounting for 76.19% of the total variance. Ashaka had the highest prevalence for both males (55.73%) and females (53.32%) with significant difference in the study sites (p < 0.05) accounting for 96.47% of the total variance. Age-group 11-20 years consistently maintain a high prevalence at all sites. The peak geometric mean intensity of 105.69 was obtained in the dry season at Lagos Iyede. Ashaka, Igbuku, Iyede-Ame, and Onogboko had heavy-intensity levels in both seasons. Overall, the intensity was lower during the wet season than the dry season, with significant variations (p < 0.05) at Awah and Itobi-Ige. Geospatial prevalence and intensity have a robust and strong positive correlation (r = 0.7178; p = 0.0129), with 51.53% of intensity variability being influenced by prevalence (R2 = 0.5153). CONCLUSION: UgS is a significant public health issue in the Ase-Niger River basin, with prevalences surpassing the national average of 29.0% which calls for MDA in these settlements.

In vitro and in silico investigation of effects of antimicrobial peptides from Solanaceae plants against rice sheath blight pathogen Rhizoctinia solani.

Rhizoctonia solani, the causative agent of sheath blight disease in rice, poses a significant threat to agricultural productivity. Traditional management approaches involving chemical fungicides have been effective but come with detrimental consequences for the ecosystem. This study aimed to investigate sustainable alternatives in the form of antifungal peptides derived from Solanaceous plant species as potential agents against R. solani. Peptide extracts were obtained using an optimized antimicrobial peptide (AMP) extraction method and desalted using the solid-phase extraction technique. The antifungal potential of peptide-rich extracts from Solanum tuberosum and Capsicum annum was assessed through in vitro tests employing the agar well diffusion method. Furthermore, peptide-protein docking analysis was performed on HPEPDOCK and HDOCK server; and molecular dynamics simulations (MDS) of 100 ns period were performed using the Gromacs 2020.4. The results demonstrated significant inhibition zones for both extracts at concentrations of 100 mg/mL. Additionally, the extracts of Solanum tuberosum and Capsicum annum had minimum inhibitory concentrations of 50 mg/mL and 25 mg/mL, respectively with minimum fungicidal concentrations of 25 mg/mL. Insights into the potential mechanisms of key peptides inhibiting R. solani targets were gleaned from in-silico studies. Notably, certain AMPs exhibited favorable free energy of binding against pathogenicity-related targets, including histone demethylase, sortin nexin, and squalene synthase, in protein-peptide docking simulations. Extended molecular dynamics simulations lasting 100 ns and MM-PBSA calculations were performed on select protein-peptide complexes. AMP10 displayed the most favorable binding free energy against all target proteins, with AMP3, AMP12b, AMP6, and AMP15 also exhibiting promising results against specific targets of R. solani. These findings underscore the potential of peptide extracts from S. tuberosum and C. annum as effective antifungal agents against rice sheath blight caused by R. solani.

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.

Entomological surveillance reveals transmission of malaria but not lymphatic filariasis in two communities in North-West Nigeria.

Malaria and lymphatic filariasis (LF) are two serious public health challenges in sub-Saharan Africa, and both diseases are transmitted by Anopheles mosquitoes. Successful control of both diseases requires detailed information on transmission dynamics; thus, this study investigated malaria and LF transmission indices in two (2) communities (Jidawa and Kargo) in North-West Nigeria. Anopheles mosquitoes were sampled from twenty-five (25) randomly selected houses from each of the two communities using pyrethrum spray collection (PSC). The samples were identified morphologically and molecularly characterised using polymerase chain reaction (PCR). Human biting rate (HBR), indoor resting density (IRD), sporozoite rate (SR) and entomological inoculation rate (EIR) were calculated using standard formulae. The thorax region of the collected samples were dissected and smeared; then, Plasmodium and Wuchereria bancrofti parasites were identified using microscopy. A total of 2417 Anopheles mosquitoes were collected, and all were identified morphologically as An. gambiae s.l. Further molecular identification of sibling species revealed that An. gambiae and An. arabiensis were the only sibling species present. A total of 818 Anopheles mosquitoes were screened for Plasmodium and Wuchereria bancrofti parasites. A total of 180 samples were positive for Plasmodium parasites (Jidawa = 151; Kargo = 29), and none was positive for W. bancrofti (0%). Result of entomological indices for malaria transmission showed that indoor resting density was higher in Jidawa (10 mosquitoes/room/night) while human biting rate (2.07 bites/person/night), sporozoite rate (29.3%) and entomological inoculation rate (0.61) were higher in Kargo. In total, 35.2% of the samples were blood-fed while 67.4% were parous. There is active transmission of malaria in the two communities but not LF, suggesting the effectiveness of mass drug administration for LF. Concerted efforts should be focused on malaria control as transmission of the disease persists.

Monitoring the Status of Soil-Transmitted Helminthiases in Non-Endemic Implementation Units: A Case Study of Borgu in Northcentral Nigeria.

Nigeria remains the most endemic country in sub-Saharan Africa (SSA) for soil-transmitted helminthiases (STH). In line with ongoing monitoring plans, we present findings from a recent analysis of STH epidemiological data in Borgu, one of the non-endemic implementation units for STH in the northcentral region of Nigeria. An overall prevalence of 8.8% was recorded for STH infection, which corresponds to a 51.9% decline from the 18.3% reported in 2013. All the infected participants (36 out of 410) had a low intensity of infection. However, more than two-thirds (69%) of the children do not have access to latrine facilities, and 45% of them walk barefoot. Prevalence was significantly associated with community, age, and parental occupation. About 21-25% reduced odds were reported in some of the study communities, and children whose parents were traders had 20 times lower odds of infection compared to those whose parents were farmers. The ongoing preventive chemotherapy program for lymphatic filariasis in the area could be responsible for the huge reduction in prevalence and intensity estimates for STH. It is therefore important to invest in monitoring transmission dynamics in other non-endemic areas to arrest emerging threats through the provision of complementary interventions including WASH facilities and other health educational tools.

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.

High pyrethroid-resistance intensity in Culex quinquefasciatus (Say) (Diptera: Culicidae) populations from Jigawa, North-West, Nigeria.

This study examined pyrethroid resistance intensity and mechanisms in Culex quinquefasciatus (Say) (Diptera: Culicidae) populations from Jigawa, North-West Nigeria. Resistance statuses to permethrin, lambda-cyhalothrin and alphacypermethrin were determined with both WHO and CDC resistance bioassays. Synergist assay was conducted by pre-exposing the populations to Piperonyl butoxide (PBO) using the WHO method. Resistance intensities to 2x, 5x and 10x of diagnostic concentrations were determined with the CDC bottle method. Species analysis and presence of knockdown mutation (Leu-Phe) were done using Polymerase Chain Reaction (PCR). Results showed that Cx. quinquefasciatus was the only Culex spp. present and "Kdr-west" mutation was not detected in all analyzed samples. Using WHO method, Cx. quinquefasciatus resistance to permethrin was detected in Dutse (12.2%) and Kafin-Hausa (77.78%). Lambda-cyhalothrin resistance was recorded only in Kafin-Hausa (83.95%) with resistance suspected in Ringim (90%). Resistance to alphacypermethrin was recorded in all locations. Pre-exposure to PBO led to 100% mortality to alphacypermethrin and lambda-cyhalothrin in Ringim while mortality to permethrin and alphacypermethrin in Dutse increased from 12.2% to 97.5% and 64.37% to 79.52% respectively. Using CDC bottle bioassay, resistance was also recorded in all populations and the result shows a significant positive correlation (R2 = 0.728, p = 0.026) with the result from the WHO bioassay. Results of resistance intensity revealed a very high level of resistance in Kafin-Hausa with susceptibility to lambda-cyhalothrin and alphacypermethrin not achieved at 10x of diagnostic doses. Resistance intensity was also high in Dutse with susceptibility to all insecticides not achieved at 5x of diagnostic doses. Widespread and high intensity of resistance in Cx. quinquefasciatus from North-West Nigeria is a major threat to the control of diseases transmitted by Culex and other mosquito species. It is a challenge that needs to be adequately addressed so as to prevent the failure of pyrethroid-based vector control tools.

Identification and characterization of sialidase-like activity in the developmental stages of Amblyomma variegatum.

Amblyomma variegatum F. are obligate hematophagous ectoparasites of livestock that serve as the vectors of Ehrlichia ruminantium (formerly known as Cowdria ruminantium), the causative agent of heartwater disease. In the light of the fact that they are blood-feeding, their salivary glands play prominent role in their acquisition of nutrients from the bloodmeal. Sialic acids are a major component of glycoprotein in mammalian blood fluid and cells. Sialome of hard ticks is still sparse. Here, for the first time, the possible expression of sialidase in A. variegatum was investigated. Our finding established the presence of type II sialidase-like activity in the three stages (larva, nymph, and adult) of the fed and unfed tick. There was no statistically significant difference in sialidase activity in the various stages of this ectoparasite (P > 0.05). The enzyme was purified by combination of salting out and ion exchange chromatography on DEAE--cellulose and hydroxylapatite columns. Characterization of the enzyme revealed that it is optimally active at 40 degrees C and pH 5.5, and is activated by bivalent cations Zn2+ or Fe2+. The enzyme has a Km of 0.023 mM and Vmax of 0.16 millimol/min with Fetuin as the substrate. To assess the susceptibility of some mammalian cells to the tick sialidase, we prepared erythrocyte ghost cells from different animals, which were incubated with the enzyme. Results revealed that the ruminant cells were better substrates. Our work and findings contribute to the preliminary characterization of the A. variegatum salivary proteome, and may pave way to the development of new acaricides.