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Maize lethal necrosis (MLN) is a maize disease caused by the maize chlorotic mottle virus (MCMV), a potyvirus which causes yield losses of 30-100%. The present study aimed to isolate nanobodies against the MCMV coat protein (CP) for the diagnosis of MLN. MCMV CP expressed in Escherichia coli was used for llama immunization. VHH (i.e. variable heavy domain of heavy chain) gene fragments were prepared from blood drawn from the immunized llama and used to generate a library in E. coli TG1 cells. MCMV specific nanobodies were selected by three rounds of phage display and panning against MCMV CP. The selected nanobodies were finally expressed in E. coli WK6 cells and purified. Eleven MCMV-specific nanobodies were identified and shown to detect MCMV in infected maize plants. Thus, our results show that nanobodies isolated from llama immunized with MCMV CP can distinguish infected and healthy maize plants, potentially enabling development of affordable MCMV detection protocols., (© 2024 The Author(s). FEBS Open Bio published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

We assessed the potential effectiveness of human milk banking and lactation support on provision of human milk to neonates admitted in the newborn unit (NBU) at Pumwani Maternity Hospital, Kenya. This pre-post intervention study collected data from mothers/caregivers and their vulnerable neonates or term babies who lacked sufficient mother's milk for several reasons admitted in the NBU. The intervention included establishing a human milk bank and strengthening lactation support. Preintervention data were collected between 5 October 2018 and 11 November 2018, whereas postintervention data were collected between 4 September 2019 and 6 October 2019. Propensity score-matched analysis was performed to assess the effect of the intervention on exclusive use of human milk, use of human milk as the first feed, feeding intolerance and duration of NBU stay. The surveys included 123 and 116 newborns at preintervention and postintervention, respectively, with 160 newborns (80 in each group) being included in propensity score matched analysis. The proportion of neonates who exclusively used human milk during NBU stay increased from 41.3% preintervention to 63.8% postintervention (adjusted odds ratio [OR]: 2.68; 95% confidence interval [CI]: 1.31, 5.53) and those whose first feed was human milk increased from 55.0% preintervention to 83.3% postintervention (adjusted OR: 5.09; 95% CI: 2.18, 11.88). The mean duration of NBU stay was 27% (95% CI: 5.8%, 44.0%) lower in the postintervention group than in the preintervention group. The intervention did not affect feeding intolerance. Integrating human milk banking and lactation support may improve exclusive use of human milk among vulnerable neonates in a resource limited setting., (© 2023 The Authors. Maternal & Child Nutrition published by John Wiley & Sons Ltd.)

Maize ( Zea mays L.) is a staple food for many households in sub-Saharan Africa (SSA) and also contributes to the gross domestic product (GDP). However, the maize yields reported in most SSA countries are very low and this is mainly attributed to biotic and abiotic stresses. These stresses have been exacerbated by climate change which has led to long periods of drought or heavy flooding and the emergence of new biotic stresses. Few reports exist which compile the biotic stresses affecting maize production in SSA. Here, five major biotic stresses of maize in Kenya are presented which are attributed to high yield losses. They include Maize lethal necrosis, fall armyworm, gray leaf spot, turcicum leaf blight and desert locusts. Maize lethal necrosis and fall armyworm are new biotic stresses to the Kenyan maize farmer while gray leaf spot, and turcicum leaf blight are endemic to the region. The invasion by the desert locusts is speculated to be caused by climate change. The biotic stresses cause a reduction in maize yield of 30-100% threatening food security. Therefore, this review focuses on the cause, control measures employed to control these diseases and future prospective. There should be deliberate efforts from the government and researchers to control biotic stresses affecting maize yields as the effect of these stresses is being exacerbated by the changing climate., Competing Interests: The authors declare that they have no competing interests., (© 2023 Njeru et al.)

Background: In Kenya, typhoid fever and invasive non-typhoidal salmonellosis present a huge burden of disease, especially in poor-resource settings where clean water supply and sanitation conditions are inadequate. The epidemiology of both diseases is poorly understood in terms of severity and risk factors. The aim of the study was to determine the disease burden and spatial distribution of salmonellosis, as well as socioeconomic and environmental risk factors for these infections, in a large informal settlement near the city of Nairobi, from 2013 to 2017., Methods: Initially, a house-to-house baseline census of 150,000 population in Mukuru informal settlement was carried out and relevant socioeconomic, demographic, and healthcare utilization information was collected using structured questionnaires. Salmonella bacteria were cultured from the blood and faeces of children < 16 years of age who reported at three outpatient facilities with fever alone or fever and diarrhea. Tests of association between specific Salmonella serotypes and risk factors were conducted using Pearson Chi-Square (χ 2 ) test., Results: A total of 16,236 children were recruited into the study. The prevalence of bloodstream infections by Non-Typhoidal Salmonella (NTS), consisting of Salmonella Typhimurium/ Enteriditis, was 1.3%; Salmonella Typhi was 1.4%, and this was highest among children < 16 years of age. Occurrence of Salmonella Typhimurium/ Enteriditis was not significantly associated with rearing any domestic animals. Rearing chicken was significantly associated with high prevalence of S. Typhi (2.1%; p = 0.011). The proportion of children infected with Salmonella Typhimurium/ Enteriditis was significantly higher in households that used water pots as water storage containers compared to using water directly from the tap (0.6%). Use of pit latrines and open defecation were significant risk factors for S. Typhi infection (1.6%; p = 0.048). The proportion of Salmonella Typhimurium/ Enteriditis among children eating street food 4 or more times per week was higher compared to 1 to 2 times/week on average (1.1%; p = 0.032)., Conclusion: Typhoidal and NTS are important causes of illness in children in Mukuru informal settlement, especially among children less than 16 years of age. Improving Water, Sanitation and Hygiene (WASH) including boiling water, breastfeeding, hand washing practices, and avoiding animal contact in domestic settings could contribute to reducing the risk of transmission of Salmonella disease from contaminated environments.