Micronutrient deficiencies in African soils and the human nutritional nexus: opportunities with staple crops.

A synthesis of available agronomic datasets and peer-reviewed scientific literature was conducted to: (1) assess the status of micronutrients in sub-Saharan Africa (SSA) arable soils, (2) improve the understanding of the relations between soil quality/management and crop nutritional quality and (3) evaluate the potential profitability of application of secondary and micronutrients to key food crops in SSA, namely maize (Zea mays L.), beans (Phaseolus spp. and Vicia faba L.), wheat (Triticum aestivum L.) and rice (Oryza sativa L.). We found that there is evidence of widespread but varying micronutrient deficiencies in SSA arable soils and that simultaneous deficiencies of multiple elements (co-occurrence) are prevalent. Zinc (Zn) predominates the list of micronutrients that are deficient in SSA arable soils. Boron (B), iron (Fe), molybdenum (Mo) and copper (Cu) deficiencies are also common. Micronutrient fertilization/agronomic biofortification increases micronutrient concentrations in edible plant organs, and it was profitable to apply fertilizers containing micronutrient elements in 60-80% of the cases. However, both the plant nutritional quality and profit had large variations. Possible causes of this variation may be differences in crop species and cultivars, fertilizer type and application methods, climate and initial soil conditions, and soil chemistry effects on nutrient availability for crop uptake. Therefore, micronutrient use efficiency can be improved by adapting the rates and types of fertilizers to site-specific soil and management conditions. To make region-wide nutritional changes using agronomic biofortification, major policy interventions are needed.

Local stakeholders' perceptions of community sensitization for school-based deworming programme in Kenya.

BACKGROUND: In Kenya, the National School-Based Deworming Programme (NSBDP) for soil-transmitted helminthes and schistosomiasis in prioritized areas has been going on since the year 2012. By the year 2013 over 6 million School Age Children (SAC) had been treated. A community sensitization supplement containing key messages and answers to frequently asked questions was developed as a guiding tool. Awareness creation methods used include county sensitization meetings, stakeholder forums, town criers and posters. To assess the local stakeholders' perceptions of community sensitization for programme implementation, a qualitative cross-sectional survey was conducted in four-sub-counties of coastal region. METHODS: In-depth interviews (IDIs) were administered to 40 purposively selected opinion leaders so as to explore their perceptions of awareness creation sources, adequacy of information given, length of period of awareness creation and period between which information is given and drugs are administered. Separate IDIs were administered to pre-school teachers (41), community health extension workers (34) and primary school teachers (38). To elicit more information, 20 focus group discussions (FGDs) categorized by gender and age were conducted among parents of school-age children. Data was audio recorded, transcribed, coded and analyzed manually by study themes. RESULTS: The most commonly reported source of information was school pupils. Due to low literacy levels, use of posters was regarded as ineffective and religious institutions, town criers and vernacular radio stations considered more effective. The information given during programme implementation was considered inadequate and use of complementary methods to reach all targeted children including the non-enrolled, and relay adequate information reported as important. Use of school and chief's meetings with health personnel being present was mentioned as a useful method that would allow for interaction with participants indicating that they did not understand why adults were not being treated. Repeated awareness creation before deworming day to serve as a reminder and to reach those missing initial messages was also mentioned as important. Furthermore, the awareness creation period needed to be extended as 85% of the participants indicated that they learnt of deworming a day before it took place or after their children had received the drugs. CONCLUSION: Awareness creation is a key factor in the success of NSBDP implementation. For programme sustainability, preferences of local stakeholders need to be considered as control of worms can only be achieved through an integrated approach of deworming, health education and use of safe water and sanitation facilities which require collaboration with local stakeholders.

The role of pre-school teachers in the control of soil-transmitted helminthes in coastal region, Kenya.

BACKGROUND: Soil transmitted helminthes (STH) are significant health problems among school-age children. In Kenya's coastal region, the prevalence among pre-school age children (PSAC) ranges from 27.8 to 66.7 %. Whereas some pre-schools are as far as 7 km from the nearest primary schools, the National School-Based Deworming Programme (NSBDP) requires the pre-school teachers to walk with the children to primary schools for deworming by trained primary school teachers. The long distances may contribute in making drug delivery ineffective and unsustainable. METHODS: To assess the pre-school teachers' knowledge, experiences and perceptions of STH and the NSBDP, a cross-sectional study using qualitative methods was conducted in four sub-counties of the Coast Region. Through purposive sampling, 41 pre-schools which are 2 or more kilometers away from a primary school were selected and in-depth interviews administered to the teachers. Separate in-depth interviews were administered to 34 community health extension workers, 40 opinion leaders and 38 primary school teachers all purposively selected to assess their perceptions of the role of pre-school teachers in the NSBDP. Data was audio recorded, transcribed, coded and analyzed manually by study themes. RESULTS: A third of the pre-school teachers were aware of signs of STHs and a half indicated that poor hygiene and sanitation practices are major causes. A majority of the pre-school teachers reported that health education and environmental sanitation are key control methods. Majority (39) had received information on NSBDP from various sources and all took part in community sensitization and in treating the pre-school children. A large majority of all study participants indicated that treating the children at pre-schools is ideal for increased coverage. Majority of the pre-school teachers perceived the NSBDP as important in improving the health status of the children. All study participants felt that the parents needed to be given adequate information on STHs and training the pre-school teachers to assist in community sensitization and drug administration would be useful. CONCLUSION: Pre-school teachers are a potential resource to the NSBDP that should be utilized to instill proper water and sanitation practices to the young children and assist in community sensitization. They should be empowered and allowed to administer treatment for STH control. County Governments, their current employers should find ways of engaging them in worm control efforts. TRIAL REGISTRATION: KEMRI SSC 2547, Registered 22 July 2013.

Associations between school- and household-level water, sanitation and hygiene conditions and soil-transmitted helminth infection among Kenyan school children.

BACKGROUND: Soil-transmitted helminths, a class of parasitic intestinal worms, are pervasive in many low-income settings. Infection among children can lead to poor nutritional outcomes, anaemia, and reduced cognition. Mass treatment, typically administered through schools, with yearly or biannual drugs is inexpensive and can reduce worm burden, but reinfection can occur rapidly. Access to and use of sanitation facilities and proper hygiene can reduce infection, but rigorous data are scarce. Among school-age children, infection can occur at home or at school, but little is known about the relative importance of WASH in transmission in these two settings. METHODS: We explored the relationships between school and household water, sanitation, and hygiene conditions and behaviours during the baseline of a large-scale mass drug administration programme in Kenya. We assessed several WASH measures to quantify the exposure of school children, and developed theory and empirically-based parsimonious models. RESULTS: Results suggest mixed impacts of household and school WASH on prevalence and intensity of infection. WASH risk factors differed across individual worm species, which is expected given the different mechanisms of infection. CONCLUSIONS: No trend of the relative importance of school versus household-level WASH emerged, though some factors, like water supply were more strongly related to lower infection, which suggests it is important in supporting other school practices, such as hand-washing and keeping school toilets clean.

Urogenital schistosomiasis in women of reproductive age and pregnant mothers in Kwale County, Kenya.

Generally, women residing in areas endemic for urinary schistosomiasis may suffer from female genital schistosomiasis which is acquired during childhood. The objective of this cross-sectional study was to estimate the prevalence and intensity of infection of Schistosoma haematobium in women of reproductive age (16-45 years) and to investigate whether S. haematobium had any effect on kidney function. A total of 394 women of known pregnancy status (158 pregnant and 236 non-pregnant) were recruited from five villages (known for their high prevalence of infection of S. haematobium) in Kwale County. Serum samples were analysed to determine levels of urea and creatinine as proxy indicators of kidney function. Data revealed that pregnant women did not, on average, have a higher prevalence or intensity of infection of urinary schistosomiasis than non-pregnant women. During pregnancy, the level of prevalence and intensity of infection of S. haematobium was highest in the first trimester (0-13 weeks), dropped in the second trimester (14-26 weeks) and rose again in the third trimester (27-40 weeks). In addition, 24.8% of women were infected with hookworm, while none were diagnosed with malaria parasites. Of 250 samples analysed for serum urea and creatinine, none had significant levels of pathology, either in pregnant or non-pregnant women. Despite World Health Organization (WHO) recommendations that pregnant women should be treated with praziquantel after the first trimester, in practice this has not been the case in many countries, including Kenya. In view of this, healthcare providers should be informed to consider treatment of pregnant women infected with schistosomiasis during antenatal visits and whenever there is mass drug administration as recommended by the WHO.

COMMUNITY KNOWLEDGE AND PERCEPTIONS ON NATIONAL SCHOOL-BASED DE-WORMING PROGRAMME.

OBJECTIVES: To determine the community level of knowledge, attitude and perception of soil transmitted helminthes and the national school-based de-worming programme in selected villages of Busia County in Kenya. DESIGN: A cross-sectional survey. SETTING: Busia and Bunyala districts in Busia County. SUBJECTS: A total of 384 participants were studied. MAIN OUTCOME MEASURES: Socio-demographic characteristics, then knowledge, causes and effects of Soil Transmitted Infections on health and education, prevention strategies, knowledge of national school-based de-worming programs, implementing strategies of the programme, benefits of the programme, community satisfaction and health seeking behaviour. RESULTS: Eating the uncooked food as a cause for soil transmitted infections constituted 27.16% (63) followed by 16.38% (38) notusing latrines, 15.95% (37) eating left over foods, 12.93% (30) eating cold food, 10.78% (25) eating not well cooked pork, 9.48% (22) eating contaminated soil, and 7.33% (17) changing of diet. One head teacher interviewed stated that "One can be able to notice if his/her child has worm infection if the child eats without getting satisfied, eating all the time and yet his belly is big."Community Health Extension Worker in the FGD stated that: "During flood seasons most of the areas in Budalangi become flooded and all latrines are filled with water and the excreta start overflowing. Most of the residents don't have shoes especially the children and therefore they are prone to the worm infection."99.57% of the parents were aware of the national school based de-worming programme of which (92%) learnt about the programme after their children were de-wormed in their various schools. Seventy five percent (174) were satisfied about the programme; 65.1% (151) and 10.3% indicated that the programme improves the children's health and student's school performance respectively. CONCLUSION: Most of the parents do not have adequate knowledge on worms, their causes, and signs and symptoms of the intestinal worms. Low educational levels and poverty levels also contribute to the lack of awareness on intestinal worms and putting the prevention measures across the board. The study also found out that the community perception towards the de-worming programme was good because the de-worming programme improved the children's health and performance in school.

PREVALENCE AND INTENSITY OF SINGLE AND MIXED SCHISTOSOMA MANSONI AND SCHISTOSOMA HAEMATOBIUM INFECTIONS IN PRIMARY SCHOOL CHILDREN IN RACHUONYO NORTH DISTRICT, HOMABAY COUNTY, WESTERN KENYA.

OBJECTIVE: To determine the prevalence andintensity of single and mixed schistosomiasis infection among primary school children in Rachuonyo North District, Homabay County in western Kenya. DESIGN: A descriptive cross sectional study. SETTING: A parasitological survey involving six primary schools in Rachuonyo North District, Homabay County. SUBJECTS: Four hundred and seventy four(474) school children, seven to 15 years old. Each child provided a urine and stool sample for diagnosis of schistosome and soil-transmitted helminth infections. Urine samples were processed using the filtration technique and the sample examined by microscopy for Schistosoma haematobium ova. Stool samples were processed by the Kato-Katz technique and the sample examined by microscopy for ova of S. mansoni and soil-transmitted helminths. RESULTS: Prevelance of S.haematobium was 37.6%, S.mansoni (12.2%), hookworm (14.6%), Ascaris lumbricoides (6.3%), Trichuris trichiura (5.3%) among the children in the participating schools. Overall, 78.6% of the children infected with S.haematobium had light infection (<50 eggs per 10 ml of urine) and the rest (21.4%) had heavy infection (50 eggs per 10 ml of urine). On the hand, 75.9% of those with S.mansoni had light infection (one to 99 eggs per gram of stool (EPG), and the rest (24.1%) had moderate infection intensities (100-399 (EPG). CONCLUSION: This is the first report in which both S.haematobium and S.mansoni are found together in the same geographic locality in high prevalence in the Lake Victoria region of western Kenya, with S. haematobium being the most predominant in some places. Rachuonyo North District becomes a new focus of mixed human schistosome infections in Kenya. The significant burden of schistosomiasis in this area highlights the need to include regular treatment for schistosomiasis in the national school based deworming programme especially now that the infection occurs in areas more than five kilometres away from the lake.

Soluble vascular cell adhesion molecule-1 induces human eosinophil migration.

BACKGROUND: Tissue eosinophilia is one of the hallmarks of allergic diseases and Th2-type immune responses including asthma. Adhesion molecules are known to play an important role in the accumulation of eosinophils in allergic inflammatory foci, and they contribute to eosinophil activation. Elevated levels of the soluble forms of adhesion molecules in the body fluid of asthmatic patients have been observed, although their pathophysiological significance remains to be fully elucidated. METHODS: Peripheral blood eosinophils were purified, and the effect of soluble vascular cell adhesion molecule-1 (sVCAM-1) on eosinophil migration was investigated using in vitro systems. RESULTS: We found that sVCAM-1 (1 to 10 mug/ml) induced eosinophil chemotaxis, rather than chemokinesis, in a concentration-dependent fashion. In addition, sVCAM-1 induced cell shape change and actin polymerization, which are necessary for cell movement. Manipulations with very late antigen (VLA)-4-neutralizing antibody and signal inhibitors indicated that the sVCAM-1-induced chemotaxis was mediated through ligand-dependent activation of tyrosine kinase Src, p38 mitogen-activated protein kinase (MAPK), and extracellular signal-regulated kinase (ERK) MAPK. Rapid phosphorylation of these signaling molecules was observed using a bead-based multiplex assay. CONCLUSION: Our results raise the possibility of sVCAM-1 in the fluid phase as a significant contributor to the heightened eosinophilic inflammatory response.

Drug efficacy of praziquantel and albendazole in school children in Mwea Division, Central Province, Kenya.

The objective of this research was to assess drug efficacy in school children after mass chemotherapy with praziquantel and albendazole conducted in Mwea Division, Kirinyaga District, Central Kenya in 2004. In total 2300 children aged between 4 and 18 years in five primary schools were selected for the study. Before mass chemotherapy, prevalence of infection was 47.4% for Schistosoma mansoni, 16.7% for Necator americanus, 1.6% for Ascaris lumbricoides, and 0.8% for Trichuris trichiura. Post-treatment stool examination was carried out 8 weeks later, and a total of 1942 stool samples were collected. Prevalence decreased to 8.6% for S. mansoni, 0.2% for N. americunus, 0 for A. lumbricoides, and 0.6% for T. trichiura. Efficacy was good for S. mansoni and N. americanus (92.6% and 95.0%, respectively). Results of the first round of treatment of school-age children in Mwea indicate a good reduction in parasite burden.

Molecular cloning, sequence analysis and expression of a novel gene induced by near-UV light in Bipolaris oryzae.

A cDNA clone derived from a novel gene (uvi-1) that is inducible by near-UV light was isolated by a differential screening procedure from a cDNA library of the fungus Bipolaris oryzae and characterized further. Sequence analysis of the clone revealed that uvi-1 encodes a protein with a putative molecular mass of 17 kDa; the UVI-1 protein shows significant similarity to a putative protein encoded by a cDNA which is expressed during appressorium formation in the rice blast fungus, Magnaporthe grisea. The corresponding genomic clone was also isolated, and Southern analysis of genomic DNA indicated the presence of a single copy of the uvi-1 gene in B. oryzae. Northern analysis showed that the uvi-1 transcripts are induced by exposure to near-UV light, but not by blue or red light. Furthermore, accumulation of uvi-1 transcripts is observed during differentiation of the appressorium.

Impact of the crayfish Procambarus clarkii on Schistosoma haematobium transmission in Kenya.

The Louisiana red swamp crayfish, Procambarus clarkii, which was introduced into east Africa in the 1950s or 1960s, has since widely dispersed. Previous work by our group has shown that P. clarkii can reduce populations of the molluscan intermediate hosts of human schistosomes through predatory and competitive interactions. Here, we investigate whether crayfish can reduce populations of Bulinus africanus and consequently, Schistosoma haematobium prevalence in school children. Children from 6 primary schools in the Machakos and Kitui Districts of Kenya were selected for study. Schools were divided into 3 experimental-control pairs. At experimental schools, crayfish were introduced into nearby aquatic habitats harboring Bulinus africanus snails and serving as S. haematobium transmission sites. Snail habitats near control schools did not receive crayfish. Six months after crayfish introduction, all infected children were treated with praziquantel. Children were then monitored quarterly for 2 years, at which time infection and reinfection rates were compared statistically between the paired schools. In one such pair, crayfish failed to establish, resulting in neither snail control nor a reduction in transmission. At the second pair of schools, the numbers of snails were decreased by the presence of crayfish, but a clear difference in infection rates in children could not be detected, primarily because drought conditions kept overall transmission rates low. At the third school pair, crayfish established well in experimental habitats, snail numbers decreased precipitously, and children at the experimental school were significantly less likely to acquire S. haematobium infections than children at the control school. Our results indicate that under certain environmental circumstances, P. clarkii exerts a significant impact on the transmission of human schistosomiasis in Kenya. Important questions remain regarding the impact of P. clarkii on Kenyan freshwater ecosystems, not the least of which is its potential to significantly influence the epidemiology of schistosomiasis in east Africa.

Two siblings with hypophosphatasia.

Two siblings with hypophosphatasia, one of whom was autopsied, were reported. The first case which was a product of a 26-year-old mother complicated by hydroamnios represented poor mineralization of the entire bones on X-ray examination and died shortly after birth. The second case weighing 1850 g delivered from the same mother had a rhizomelic micromelia and poor visualization of the skull, long bones and vertebral bones on X-ray at postmortem. The autopsy on the second case showed small thoracic cage with rachitic rosaries of ribs, membranous skull and poorly ossified vertebral and long bones. Microscopically, there was a marked disturbance of both enchondral and membranous ossifications similar to the histology of rachitis. A biochemical examination showed low alkaline phosphatase, high calcium and normal PTH in the serum. Further examination of their family revealed relatively low level of alkaline phosphatase of the parents and one of their brothers which suggsted they were carriers of hypophosphastasia. Previous reports on hypophosphatasia were reviewed and differential diagnosis of hypophosphatasia from the other congenital dwarfisms was discussed.