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

Helminthiasis and hygiene conditions of schools in Ikenne, Ogun State, Nigeria.

BACKGROUND: A study of the helminth infection status of primary-school children and the hygiene condition of schools in Ikenne Local Government Area of Ogun State, Nigeria was undertaken between November 2004 and February 2005 to help guide the development of a school-based health programme. METHODS AND FINDINGS: THREE PRIMARY SCHOOLS WERE RANDOMLY SELECTED: two government-owned schools (one urban and the other rural) and one urban private school. No rural private schools existed to survey. A total of 257 schoolchildren aged 4-15 y, of whom 146 (56.8%) were boys and 111 (43.2%) were girls, took part in the survey. A child survey form, which included columns for name, age, sex, and class level, was used in concert with examination of stool samples for eggs of intestinal helminths. A school survey form was used to assess the conditions of water supply, condition of latrines, presence of soap for handwashing, and presence of garbage around the school compound. The demographic data showed that the number of schoolchildren gradually decreased as their ages increased in all three schools. The sex ratio was proportional in the urban school until primary level 3, after which the number of female pupils gradually decreased, whereas in the private school, sexes were proportionally distributed even in higher classes. The prevalence of helminth infection was 54.9% of schoolchildren in the urban government school, 63.5% in the rural government school, and 28.4% in the urban private school. Ascaris lumbricoides was the most prevalent species, followed by Trichuris trichiura, Taenia species, and hookworm in the three schools. Prevalence of infection in the government-owned schools was significantly higher than in the private school (chi(2) = 18.85, df = 2, p<0.0005). A survey of hygiene conditions in the three schools indicated that in the two government schools tapwater was unavailable, sanitation of latrines was poor, handwashing soap was unavailable, and garbage was present around school compounds. In the private school, in contrast, all hygiene indices were satisfactory. CONCLUSIONS: These results indicate that burden of parasite infections and poor sanitary conditions are of greater public health importance in government-owned schools than in privately owned schools. School health programmes in government-owned schools, including deworming, health education, and improvement of hygiene conditions are recommended

Demographic Characteristics of Schoolchildren in Government-Owned Urban and Rural Schools and an Urban Private School, Ikenne Local Government Area, Ogun State, Nigeria.

<p>The pair of bars on the right show age frequency data grouped by sex for an urban privately owned school. *The pair of bars on the left and in the center show data from an urban and a rural government school, respectively.</p

The Prevalence of Intestinal Helminth Infections by Age Group and Sex of Schoolchildren in the Government-Owned (Urban and Rural) and Private (Urban) Schools.

<p>The Prevalence of Intestinal Helminth Infections by Age Group and Sex of Schoolchildren in the Government-Owned (Urban and Rural) and Private (Urban) Schools.</p

The Prevalence of Intestinal Helminth Infections in Government-Owned (Urban and Rural) and Privately Owned (Urban) Schools.

<p>The Prevalence of Intestinal Helminth Infections in Government-Owned (Urban and Rural) and Privately Owned (Urban) Schools.</p

Distribution of ascariasis, trichuriasis and hookworm infections in Ogun State, Southwestern Nigeria.

BackgroundAscariasis, Trichuriasis and Hookworm infections poses a considerable public health burden in Sub-Saharan Africa, and a sound understanding of their spatial distribution facilitates to better target control interventions. This study, therefore, assessed the prevalence of the trio, and mapped their spatial distribution in the 20 administrative regions of Ogun State, Nigeria.MethodsParasitological surveys were carried out in 1,499 households across 33 spatially selected communities. Fresh stool samples were collected from 1,027 consenting participants and processed using ether concentration method. The locations of the communities were georeferenced using a GPS device while demographic data were obtained using a standardized form. Data were analysed using SPSS software and visualizations and plotting maps were made in ArcGIS software.ResultsFindings showed that 19 of the 20 regions were endemic for one or more kind of the three infections, with an aggregated prevalence of 17.2%. Ascariasis was the most frequently observed parasitic infection in 28 communities with a prevalence of 13.6%, followed by hookworm infections with a prevalence of 4.6% while Trichuriasis was the least encountered with a prevalence of 1.7%. The spatial distribution of infections ranges between 5.3-49.2% across the regions. The highest and lowest distribution of overall helminth infections was recorded in Egbado South and Egbado North respectively. Nine regions had infection status between 20.0%-49.2%, while 10 regions had infection status between 5.3%-15.8%.ConclusionThis study provides epidemiological data on the prevalence and spatial distribution of ascariasis, trichuriasis and hookworm infections which will add to the baseline data and guide the public health officers in providing appropriate control strategies in the endemic communities