Geochemical Characteristics of Soil in Relation to Occurrence of Entomopathogenic Nematodes (EPNs) in Osogbo, Osun State, Nigeria

The occurrence and abundance of entomopathogenic nematodes (EPNs) vary across locations, and this has been attributed to many factors including soil physico-chemical properties. This study examined the influence of selected soil chemicals on the occurrence of EPNs under different cultivated lands in Osun state, Southwestern Nigeria. EPNs were isolated from 23.33% of the soil samples in selected sites using decantation and centrifugation method and nematodes observed under standard microscopy were identified based on morphological analysis of infective juveniles (IJs). This study has revealed the presence of nematodes of the families Steinernema and Heterorhabditis in the sampled soils. Soil chemical properties, including sodium (Na), carbon (C), phosphorus (P), magnesium (Mg), potassium (K), calcium (Ca), zinc (Zn), and iron (Fe) of the soil samples containing EPNs were determined following standard laboratory methods. Soil moisture contents of the sampled soils were also determined. Association of soil chemical characteristic and soil moisture content with the occurrence of EPNs was determined. There were statistically significant differences between mean soil chemical properties such as Na, C, P, Mg, K, Ca, Zn and Fe and soil chemical levels of soil samples with EPNs and soil samples without EPNs at P ≤ 0.05. However, soil moisture was found to significantly influence EPNs’ counts in positive soil samples. EPNs were found in soils of varying soil chemical levels, with individual species preferring a certain degree of chemicals (potassium (K) 267.83 mg, sodium (Na) 190.01 mg and iron (Fe), 155.80 mg). Soil fertility management that includes the use of fertilizers that contain the specific soil chemicals is required for occurrence of the EPNs. Keywords: Entomopathogenic nematodes; soil chemicals; Moisture content; influenc

Development of Guinea Corn Husk-Cow Hair Hybrid Fibre Reinforced Cement Composite

This research work presents the application of guinea corn husk (GCH) and cow hair (CH) fibres as reinforcement in cement composite. The influence of the hybrid fibre volume on the flexural performance of the composite has been studied experimentally. The mechanical (flexural strength) and physical (density, water absorptivity, moisture content) characteristics of the GCH-CH hybrid fibre reinforced composite were evaluated. The highest flexural strength was 22.37MPa, exhibited by the composite reinforced with 15% (12.5% GCH & 2.5% CH) hybrid fibre. The density of the GCH-CH hybrid composite ranged from 1019 to 1963 kg/m3. The water absorptivity varied from 22.59 to 38.16% and the moisture content ranged from 3.32 to 11.28%. These limits are within the range in standard therefore, the performance of the composite satisfies the requirements of BS EN 12467 standard for ceiling board

Urinary Schistosomiasis and Its Potential for Cancer and Hepato-Renal Function Alterations among the Residents of Asejire Dam, South-Western Nigeria

Urinary schistosomiasis is of public health significance in sub-Saharan Africa with its prevalence being linked to carcinogenesis. However, there is a paucity of data to support this relationship. This study explored the prevalence and intensity of Schistosoma haematobium infections and its associations with cancer and hepatorenal function alterations in villages along the Asejire dam in the State of Osun, Nigeria. Urine samples from 152 consented participants (aged 18–75 years) from four communities were collected and examined for Schistosoma haematobium using the microscopy method. The blood serum of randomly selected infected and non-infected individuals (10 per group) was screened for tumor, inflammatory and hepato-renal function biomarkers. From the results, only one out of the four communities recorded cases of schistosomiasis with a prevalence of 26.5% (22/83) and overall infection prevalence was 14.47% (22/152). There was no statistical difference (p ˃ 0.05) in kidney, liver antioxidants, and lipid peroxidation markers in the infected and non–infected participants. The concentrations of antioxidants, inflammatory, and tumor markers were higher in Schistosoma infected individuals as compared with non-infected individuals. This justifies the need to monitor schistosomiasis-infected individuals for tumor, inflammatory and hepato-renal function biomarkers before they develop into cancer, liver, and kidney failure. Keywords:    Urinary Schistosomiasis; tumor; and inflammatory markers; antioxidants; hepato-renal function; Asejire dam Nigeri

Biting on human body parts of Simulium vectors and its implication for the manifestation of Onchocerca nodules along Osun River, southwestern Nigeria

Background: The biting preference of Simulium vectors has been known to influence the distribution ofOnchocerca nodules and microfilariae in human body. There is, however, variation in biting pattern of Simuliumflies in different geographical locations. This study investigates the biting pattern on human parts by Simuliumvectors along Osun river system where Simulium soubrense Beffa form has been implicated as the dominantvector and its possible implication on the distribution of Onchocerca nodules on human body along the river.Methods: Flies were collected by consented fly capturers on exposed human parts namely head/neck region,arms, upper limb and lower limb in Osun Eleja and Osun Budepo along Osun river in the wet season (August–September) and the dry season (November–December) in 2008. The residents of the communities were alsoscreened for palpable Onchocerca nodules.Results: The results showed that number of flies collected below the ankle region was significantly higher thanthe number collected on other exposed parts (p <0.05) while the least was collected on head/neck region in bothseasons. The lower trunk was the most common site (60%) for nodule location at Osun Eleja followed by uppertrunk (40%). Nodules were not found in the head and limb regions. At Osun Budepo, the upper trunk was themost common site of the nodule location (53.8%) followed by the lower trunk (38.5%) and head region (7.7%).Conclusion: Though, most of the flies were caught at the ankle region, the biting of other parts coupled with thepresence of nodules at the head and upper trunk regions showed that Simulium vectors could obtain microfilariaefrom any part of the body, thus increasing the risk of onchocerciasis transmission

Prevalence and effect of schistosome and soil-transmitted helminth infection on labour input in rice-growing communities of Ogun State, Nigeria

Schistosomiasis and soil-transmitted helminthiasis (STH) are public health problems in communities which lack basic social amenities with poor hygienic conditions. Studies were carried out to determine the prevalence and effect of schistosomes and soil-transmitted helminths infection on labour input on rice production in 9 rice-growing communities of Ogun State. Parasitological examinations of urine and faecal samples, and structured questionnaires were conducted on 243 consented individuals from May 2009 to March 2010. The results showed an overall prevalence of 17% for Ascaris lumbricoides, 12% for hookworms, 2% for Trichuris trichiura, 1% for Schistosoma haematobium and 1% for Schistosoma mansoni. A. lumbricoides and hookworms were more prevalent in Agbajege (25%), and varied in the other 8 communities. T. trichiura was prevalent in three communities, Agbajege (5%), Akodu (4.2%), and Moloko-Asipa (4.8 %); S. haematobium was prevalent only in Ayedere (2.6%) and Lufoko (8%), while S. mansoni was prevalent only in Moloko-Asipa (9.5%). Infections among the gender were varied as 26.3 % of males and 33.8 % of females had an overall prevalence of: A. lumbricoides (16.8%), hookworms (11.8%), T. trichiura (1.6%), S. haematobium (1.1%) and S. mansoni (1.1%). On frequency of infection to incapacitation per year, 45% of respondents were incapacitated 1-2 times, 27% 3-4 times and 19% were incapacitated more than 4 times. Understanding the effect of these two diseases will not only improve the health status of residents but also increase their productivity and ensure food security

Biting behaviour of Simulium damnosum complex and Onchocerca volvulus infection along the Osun River, Southwest Nigeria

<p>Abstract</p> <p>Background</p> <p>Studies on biting behaviours and infectivity status of insect vectors are pre-requisites in understanding the epidemiology of the vector- borne diseases and planning effective control measures. A longitudinal study was carried out to investigate the transmission index of <it>Simulium damnosum </it>complex species along Osun River, South Western Nigeria. Adult flies were collected on human attractants from 07:00 to 18:00 hours for two consecutive days from February 2008 to June 2009 at three communities: Osun Eleja, Osun Ogbere and Osun Budepo. The infectivity rate was determined by dissection and Polymerase Chain Reaction amplification (PCR) of 0-150 genes of <it>Onchocerca </it>parasite using the pool screening technique.</p> <p>Results</p> <p>The results indicated that the majority of the flies collected at the three sampling points were nulliparous as they accounted for 53.90%, 57.86% and 59.58% of the flies dissected at Osun Budepo, Osun Ogbere and Osun Eleja, respectively. The parous rate was higher during the dry season than the wet season but the difference was not statistically significant (<it>p </it>< 0.05). The biting activity of the parous flies showed two peaks at Osun Budepo and three peaks at Osun Eleja and Osun Ogbere. Of the 1,472 flies dissected and 1,235 flies screened by molecular method, none was infected with <it>Onchocerca </it>parasite at the three sampling points however the annual biting rates at the three communities were higher than 1,000 considered as tolerable value for a person living in an onchocerciasis zone by Word Health Organization.</p> <p>Conclusion</p> <p>The study has provided the baseline data for further study on onchocerciasis transmission dynamics and the need to intercept man- simuliid vector contact at the study area.</p

Evaluation of a community-based trapping program to collect simulium ochraceum sensu lato for verification of onchocerciasis elimination

Background: Collection of the black fly vectors of onchocerciasis worldwide relies upon human landing collections. Recent studies have suggested that the Esperanza Window Trap baited with a human scent lure and CO2 had the potential to replace human hosts for the collection of Simulium ochraceum sensu lato in Southern Chiapas focus, Mexico. The feasibility of utilizing these traps in a community-based approach for the collection of S. ochraceum s.l. was evaluated. Methodology/Principal findings: Local residents of a formerly endemic extra-sentinel community for onchocerciasis were trained to carry out collections using the traps. The residents operated the traps over a 60-day period and conducted parallel landing collections, resulting in a total of 28,397 vector black flies collected. None of the flies collected were found to contain parasite DNA when tested by a polymerase chain reaction assay targeting a parasite specific sequence, resulting in a point estimate of infection in the vectors of zero, with an upper bound of the 95% confidence interval 0.13 per 2,000. This meets the accepted criterion for demonstrating an interruption of parasite transmission. Conclusions/Significance: These data demonstrate that Esperanza Window Traps may be effectively operated by minimally trained residents of formerly endemic communities, resulting in the collection of sufficient numbers of flies to verify transmission interruption of onchocerciasis. The traps represent a viable alternative to using humans as hosts for the collection of vector flies as part of the verification of onchocerciasis elimination

Aedes albopictus in northeast Mexico: An update on adult distribution and first report of parasitism by Ascogregarina taiwanensis

ABSTRACT Background &amp; objectives: Aedes albopictus has been known as efficient vector of dengue in Asian countries and its wide displacement of Ae. aegypti has been documented in many parts of the world. The present survey was carried out to update the distribution of Ae. albopictus in northeast Mexico and to report the first record of parasitism of mosquitoes by Ascogregarina taiwanensis in Mexico

Identification of human semiochemicals attractive to the major vectors of onchocerciasis

Background: Entomological indicators are considered key metrics to document the interruption of transmission of Onchocerca volvulus, the etiological agent of human onchocerciasis. Human landing collection is the standard employed for collection of the vectors for this parasite. Recent studies reported the development of traps that have the potential for replacing humans for surveillance of O. volvulus in the vector population. However, the key chemical components of human odor that are attractive to vector black flies have not been identified. Methodology/Principal Findings: Human sweat compounds were analyzed using GC-MS analysis and compounds common to three individuals identified. These common compounds, with others previously identified as attractive to other hematophagous arthropods were evaluated for their ability to stimulate and attract the major onchocerciasis vectors in Africa (Simulium damnosum sensu lato) and Latin America (Simulium ochraceum s. l.) using electroantennography and a Y tube binary choice assay. Medium chain length carboxylic acids and aldehydes were neurostimulatory for S. damnosum s.l. while S. ochraceum s.l. was stimulated by short chain aliphatic alcohols and aldehydes. Both species were attracted to ammonium bicarbonate and acetophenone. The compounds were shown to be attractive to the relevant vector species in field studies, when incorporated into a formulation that permitted a continuous release of the compound over time and used in concert with previously developed trap platforms. Conclusions/Significance: The identification of compounds attractive to the major vectors of O. volvulus will permit the development of optimized traps. Such traps may replace the use of human vector collectors for monitoring the effectiveness of onchocerciasis elimination programs and could find use as a contributing component in an integratedvector control/drug program aimed at eliminating river blindness in Africa

Design and methods for a quasi-experimental pilot study to evaluate the impact of dual active ingredient insecticide-treated nets on malaria burden in five regions in sub-Saharan Africa

Background:Vector control tools have contributed significantly to a reduction in malaria burden since 2000, primar‑ily through insecticidal‑treated bed nets (ITNs) and indoor residual spraying. In the face of increasing insecticide resist‑ance in key malaria vector species, global progress in malaria control has stalled. Innovative tools, such as dual active ingredient (dual‑AI) ITNs that are effective at killing insecticide‑resistant mosquitoes have recently been introduced. However, large‑scale uptake has been slow for several reasons, including higher costs and limited evidence on their incremental effectiveness and cost‑effectiveness. The present report describes the design of several observational studies aimed to determine the effectiveness and cost‑effectiveness of dual‑AI ITNs, compared to standard pyre‑throid‑only ITNs, at reducing malaria transmission across a variety of transmission settings.Methods:Observational pilot studies are ongoing in Burkina Faso, Mozambique, Nigeria, and Rwanda, leveraging dual‑AI ITN rollouts nested within the 2019 and 2020 mass distribution campaigns in each country. Enhanced surveil‑lance occurring in select study districts include annual cross‑sectional surveys during peak transmission seasons, monthly entomological surveillance, passive case detection using routine health facility surveillance systems, and studies on human behaviour and ITN use patterns. Data will compare changes in malaria transmission and disease burden in districts receiving dual‑AI ITNs to similar districts receiving standard pyrethroid‑only ITNs over three years. The costs of net distribution will be calculated using the provider perspective including financial and economic costs, and a cost‑effectiveness analysis will assess incremental cost‑effectiveness ratios for Interceptor® G2, Royal Guard®, and piperonyl butoxide ITNs in comparison to standard pyrethroid‑only ITNs, based on incidence rate ratios calcu‑lated from routine data.Conclusions:Evidence of the effectiveness and cost‑effectiveness of the dual‑AI ITNs from these pilot studies will complement evidence from two contemporary cluster randomized control trials, one in Benin and one in Tanzania, to provide key information to malaria control programmes, policymakers, and donors to help guide decision‑making and planning for local malaria control and elimination strategies. Understanding the breadth of contexts where these dual‑AI ITNs are most effective and collecting robust information on factors influencing comparative effectiveness could improve uptake and availability and help maximize their impact