The adverse effects of albendazole and praziquantel in mass drug administration by trained schoolteachers

Eastern and Southern Africa Centre of International Parasite Control (ESACIPAC) conducted stool examinations for soil transmitted helminthiases (STH) and Schistosoma mansoni, among school children in Mwea Division, Central Kenya where both infections are endemic. Mass drug administrations (MDAs) were then conducted in 2004 and 2005 using schoolteachers trained on how to administer treatment, physically and psychologically prepare the children to take the medication, have them eat before treatment, handle minor and refer serious side effects to local health facilities. Local health workers were on standby to help manage severe side effects. This study examined side effects of the drugs and the teachers’ preparedness to handle the children when such effects occurred. No serious side effects requiring referral to the health centre occurred and the minor ones observed were temporal. In 2005 children in Mwea schools were treated with albendazole 400mg and praziquantel 40mg/kg body weight while those of Ndia, a neighboring division treated with only albendazole 400mg since there was low S.mansoni prevalence. Monitoring of side effects was done in two schools of Ndia and in three of Mwea through a questionnaire distributed to grade three pupils a week after treatment. Of 73 pupils from Mwea, 49.7% reported incidences of stomachache, vomiting/nausea, headache and dizziness whereas 39.2% of 186 from Ndia experienced incidences of cough, stomachache and headache. This shows that more pupils from Mwea, (albendazole and praziquantel) than from Ndia (albendazole alone) experienced minor side effects. These results show that both drugs have temporary, minor side effects, which can be managed by trained schoolteachers by ensuring that the school children do not swallow the drugs on an empty stomach and rest immediately after swallowing the drugs but should be closely monitored by health personnel. In this study, one trained schoolteacher could administer treatment to three hundred children in one day, which makes the approach cost effective and should be adopted nationally.Keywords: albendazole, praziquantel, soil transmitted helminthiasis, schistosomiasi

A fouryear followup of school children after masstreatment for Schistosomiasis and Soil Transmitted Helminths in Mwea, Central Kenya

Poly-parasitism infections are common in school children in tropical regions, especially in Africa. In a school based schistosomiasis and soil-transmitted helminths de-worming model project in Mwea, Kenya, approximately 40,000 school age children from 86 schools were treated annually with a standard dose of praziquantel (40mg/kg body weight) and albendazole (400mg). A cohort of approximately 2,300 children from 5 sentinel schools were followed up at multiple time points each year for four years and examined for intestinal helminths (Schistosoma mansoni, Trichuris trichiura, Hookworm (Necator americanus) and Ascaris lumbricoides). The overall prevalence of infection in the five schools before treatment was 47.4% for S. mansoni, 16.7% for N. americanus, 0.8% for T. trichiura and 1.7% for A. lumbricoides. The mean intensity of infection, as measured by eggs per gram of faeces (epg) was 146.2 for S. mansoni, 36.3 for N. americanus 1.0 for T. trichiura and 35.8 for A. lumbricoides. After 4 rounds of treatment, prevalence of S. mansoni reduced significantly by 88.7% to 5.4% (95%CI=3.6% -7.1%), a 97.1% reduction. The prevalence and intensity of S. mansoni infection varied by school according to its proximity to irrigated area, with those schools closest to the irrigated areas presenting higher infection prevalence and intensity. Re-infection with schistosomiasis following treatment was observed and is likely to reflect continued environmental transmission due to non-treatment of the adult population. Soil-transmitted helminths are less prevalent in the cohort, with corresponding lower intensity. This may allow albendazole treatment to be reduced to every 2 or 3 years. This study has shown that periodic administration of anthelminthic drugs reduces the prevalence and intensity (which is likely to be a close proxy of morbidity) of intestinal parasitic infections in school-age children. Adults in the community could also be targeted where resources allow in order to further increasing the effectiveness of de-worming programmes. Keywords: Soil transmitted helminths, Schistosomiasis, school age, prevalence, Intensity, mass de-worming, school childre

A fumonisins immunosensor based on polyanilino-carbon nanotubes doped with palladium telluride quantum dots

An impedimetric immunosensor for fumonisins was developed based on poly(2,5-dimethoxyaniline)-multi-wall carbon nanotubes doped with palladium telluride quantum dots onto a glassy carbon surface. The composite was assembled by a layer-by-layer method to form a multilayer film of quantum dots (QDs) and poly(2,5-dimethoxyaniline)- multi-wall carbon nanotubes (PDMA-MWCNT). Preparation of the electrochemical immunosensor for fumonisins involved drop-coating of fumonisins antibody onto the composite modified glassy carbon electrode. The electrochemical impedance spectroscopy response of the FB1 immunosensor (GCE/PT-PDMA-MWCNT/anti-Fms-BSA) gave a linear range of 7 to 49 ng L−1 and the corresponding sensitivity and detection limits were 0.0162 kΩ L ng−1 and 0.46 pg L−1 , respectively, hence the limit of detection of the GCE/PT-PDMA-MWCNT immunosensor for fumonisins in corn certified material was calculated to be 0.014 and 0.011 ppm for FB1, and FB2 and FB3, respectively. These results are lower than those obtained by ELISA, a provisional maximum tolerable daily intake (PMTDI) for fumonisins (the sum of FB1, FB2, and FB3) established by the Joint FAO/WHO expert committee on food additives and contaminants of 2 μg kg−1 and the maximum level recommended by the U.S. Food and Drug Administration (FDA) for protection of human consumption (2–4 mg L−1 )

Spatial distribution and risk factors of Schistosoma haematobium and hookworm infections among schoolchildren in Kwale, Kenya

Background: Large-scale schistosomiasis control programs are implemented in regions with diverse social and economic environments. A key epidemiological feature of schistosomiasis is its small-scale heterogeneity. Locally profiling disease dynamics including risk factors associated with its transmission is essential for designing appropriate control programs. To determine spatial distribution of schistosomiasis and its drivers, we examined schoolchildren in Kwale, Kenya. Methodology/Principal findings: We conducted a cross-sectional study of 368 schoolchildren from six primary schools. Soil-transmitted helminths and Schistosoma mansoni eggs in stool were evaluated by the Kato-Katz method. We measured the intensity of Schistosoma haematobium infection by urine filtration. The geometrical mean intensity of S. haematobium was 3.1 eggs/10 ml urine (school range, 1.4?9.2). The hookworm geometric mean intensity was 3.2 eggs/g feces (school range, 0?17.4). Heterogeneity in the intensity of S. haematobium and hookworm infections was evident in the study area. To identify factors associated with the intensity of helminth infections, we utilized negative binomial generalized linear mixed models. The intensity of S. haematobium infection was associated with religion and socioeconomic status (SES), while that of hookworm infection was related to SES, sex, distance to river and history of anthelmintic treatment. Conclusions/Significance: Both S. haematobium and hookworm infections showed micro-geographical heterogeneities in this Kwale community. To confirm and explain our observation of high S. haematobium risk among Muslims, further extensive investigations are necessary. The observed small scale clustering of the S. haematobium and hookworm infections might imply less uniform strategies even at finer scale for efficient utilization of limited resources

Formulation of slow release NPK fertilizer (cellulose-graft-poly(acrylamide)/nano-hydroxyapatite/soluble fertilizer) composite and evaluating its N mineralization potential

Polymer nano-composite fertilizer formulation has the potential to enhance nutrient use efficiency. Slow release fertilizer (SRF) composite was formulated by incorporating nano-hydroxyapatite (nano-HA) and water soluble fertilizers (urea, (NH4)2HPO4 and K2SO4) into water hyacinth cellulose-graft-poly(acrylamide) polymer hydrogel. Fourier Transform Infra-red spectra revealed existence of chemical interaction between the monomer, cellulose, urea and nano-HA. The release of nutrients was assessed using laboratory incubation experiment. Significantly higher content of mineral nitrogen (MN) was observed in the first 4 weeks in conventional fertilizer (CF) compared to SRF treatments and the control. MN content in SRF treatments increased considerably between the 8th and 12th week, and declined in the 16th week. The values of potentially mineralizable N estimated using first order kinetics model related well to the observed cumulative MN at 16th week. No significant difference was observed between CF and SRF treatments for available P content in the 2nd week. Significantly higher P content was observed in CF compared to SRF treatment in the 4th week, whereas in the 8th week, some SRFs released significantly higher content than CF. Available P peaked in the 8th week in all the treatments and remained constant at 12th and 16th week. Availability of P in SRFs increased with increased content of soluble P and decreased content of nano-HA. Exchangeable K showed less variation during the incubation period, suggesting short release time. The data revealed reduced chances of leaching losses and toxic effect to the plant roots, as well as synchronized nutrient release and requirement by crops. Keywords: Nano-composite, Polymer hydrogel, Chemical interaction, Incubation experiment, Kinetics mode

PROPIEDADES HIDRAULICASL DEL UN NITISOL EN KABETE, KENYA

Water relations are among the most important physical phenomena that affect the use of soils for agricultural, ecological, environmental, and engineering purposes. To formulate soil-water relationships, soil hydraulic properties are required as essential inputs. The most important hydraulic properties are the soil-water retention curve and the hydraulic conductivity. The objective of this study was to determine the soil hydraulic properties of a Nitisol, at Kabete Campus Field Station. Use of an internal drainage procedure to characterize the hydraulic properties and soil and water retention curves allowed for the establishment of the moisture and matric potential at field capacity and permanent wilting point. The Bt2 (84 -115) and Bt3 (115 - 143 cm) had the highest clay contents of 619 compared to Ap, AB and Bt1 horizons. The PWP was attained at soil moisture contents of 0.223, 0.284, 0277, 0.307 and 0.314 m3m-3 in the Ap, AB, Bt1, Bt2, and Bt3 horizons, respectively. Horizontal saturated hydraulic conductivity (Ksat) was high at 6.0 cm hr-1 in Ap horizon and decreased to 0.4 cm hr-1 in the subsurface horizon (Bt3). Ksat in the vertical direction was higher than horizontal and ranged from 8.3 cm hr-1 in surface layer to 0.6 cm hr-1 in Bt3 horizon, with exception of Bt1 and Bt2 where horizontal Ksat was greater than vertical. The Ap horizon also had the highest crop extractable water. Though the AB and Bt1 had the same water content at low matric suction, the variation was very wide as the SWRC approached saturation point. Bt1 and Bt2 also had similar water contents at suction range of – 7kPa after which Bt1, tended towards Bt3. Bt3 had the narrowest range of crop extractable water and thus was attributed to texture. The Bt3 retained the most amount of water at 0.314 m3m-3concluding that θPWP increased with depth. The total available water capacity between FC and PWP in the profile was 79.2 mm m-1. The study observed that the field capacity, crop available water contents and hydraulic conductivities were influenced positively by soil organic matter. The Van Genuchten parameters of air entry value (α) and pore size distribution (n) indicated that pore size distribution was not even in the AP and AB horizons. The field capacity was attained at higher matric potential at -5kPa for Bt1 while Bt2 and AP, AB, Bt2 and Bt3 was at -10kPa.The functional relationship, K(θ) = aθb that deals with water redistribution as a result of soil hydraulic properties and evaporative demand of the atmosphere was highly correlated to soil moisture content and texture with R2 values > 0.85

Chronic clinical manifestations related to Wucherieria bancrofti infection in a highly endemic area in Kenya

Clinical examinations were conducted in an effort to provide baseline data for a pilot filariasis elimination programme implemented in a Wuchereria bancrofti-endemic focus in Malindi district, Kenya. Of 186 mates aged 15 years and above examined, 64 individuals (34.4%) had hydrocele, and the prevalence of the manifestation in those above 40 years old was 55.3%. The prevalence of Leg lymphoedema in persons aged 15 years and above was 8.5%, with a higher rate in mates (12.6%) than in females (5.7%). The overall prevalence of inguinal adenopathy was 8.6%, and mates had a significantly higher (12.9%) prevalence of adenopathy than females (5.1%) (P < 0.001). The data in the present study provided support for consideration of filarial infection as a possible cause of inguinal lymphadenopathy in bancroftian filariasis-endemic areas. The results of this study also indicate that Lymphatic filariasis is a serious public health problem in the northern coastal areas and morbidity control programmes should be implemented to alleviate the suffering of those affected. (c) 2006 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved

Impact of two rounds of mass treatment with diethylcarbamazine plus albendazole on Wuchereria bancrofti infection and the sensitivity of immunochromatographic test in Malindi, Kenya

Annual single-dose mass treatment of endemic populations with a combination of either diethylcarbamazine (DEC) or ivermectin plus albendazole is recommended as the mainstay of lymphatic filariasis elimination programmes. We evaluated the impact of two rounds of annual mass drug administration (MDA) of DEC and albendazole on bancroftian filariasis in a pilot elimination programme in an endemic area of Kenya. Overall prevalence of microfilaraemia decreased by 65.4%, whereas community microfilarial load decreased by 84% after the two MDAs. The prevalence of parasite antigenaemia determined by immunochromatographic test (ICT) declined significantly by 43.5% after the two MDAs. We also studied the effect of mass treatment on the sensitivity of the ICT. Although the sensitivity of the test before treatment was high (89.9%; K =0.909) sensitivity was lower after two MDAs (59.3%; K = 0.644). The finding raises concern about the reliability of the ICT in long-term monitoring of infection and for establishing programmatic endpoints. The results of the present study indicate a relatively high effectiveness of MDA using a DEC/albendazole combination against Wuchereria bancrofti infection and, therefore, it may be a useful strategy to eliminate lymphatic filariasis in onchocerciasis-free areas. (c) 2008 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved

Research Dissemination Strategies Used by Kenya Medical Research Institute Scientists

Background:&nbsp;Dissemination of research findings is acknowledged as an important component of any research process. Implementation of research findings into practice or policy is necessary for improving outcomes in the targeted community. Given the context and dynamic environment in which researchers operate, there is need to find out existing gaps in terms of disseminating research findings to key stakeholders. The objective of this study was to investigate the health research dissemination strategies used by Kenya Medical Research Institute (KEMRI) researchers. &nbsp; Methods:&nbsp;This was a mixed-method study employing concurrent sequence (use of both qualitative and quantitative) methods of data collection. The study was conducted in KEMRI’s 10 centres spread in 3 geographical areas: Kisumu, Kilifi, and Nairobi counties. Potential respondents were identified through purposive sampling. Three inter-related data collection methods were employed in this study. These methods included key informant interviews with: (a) MoH officials from county government; (b) KEMRI researchers; and (c) key KEMRI departments, namely Corporate Affairs and the library. Additionally, secondary sources of information, such as scientific reports, KEMRI annual reports, and financial statements, were also reviewed. &nbsp; Results:&nbsp;Publication of papers in peer-reviewed journals was mentioned as the most common method of dissemination of research findings. Scientists published in 353 peer-reviewed journals (or publishing houses) between the years 2002 and 2015.&nbsp; Over 92.7% of these publications were in international peer-reviewed journals. Conferences and workshops were also mentioned. In the absence of a centralised electronic KEMRI publication database, the research team extracted and collated a publication lists from KEMRI annual reports and financial statements. This was limiting since it did not have an exhaustive list of all publications by KEMRI scientists. Only 3 respondents mentioned having written policy briefs or engaged the media as part of dissemination channels. The media representatives cited the use of social media (Facebook and Twitter) as another channel that KEMRI scientists could exploit. Challenges in dissemination included lack of knowledge on research translation leading to poor synthesis of research outputs as well as selective reporting by the media. &nbsp; Conclusion:&nbsp;Publications in peer-reviewed journals was the most preferred channel of communicating scientific outputs. Conferences and writing of policy briefs were the other sources of dissemination. We recommend that KEMRI dissemination channels should go well beyond simply making research available through the traditional vehicles of journal publications and scientific conference presentations but establish institutional mechanism which would facilitate extracting the main messages or key implications derived from research results and communicating them to stakeholders in attractive ways that would encourage them to factor the research implications into their work