Mycotoxin hazards in the Kenyan food and feed market - A retrospective study

Mycotoxins are toxic fungal metabolites naturally found in food and feed as contaminants. Animal feed and human food samples (n=1818) from three major Kenyan laboratories were categorized as compliant and non-compliant according to Kenya, America (USA) and Europe (EU) mycotoxin regulatory limits. Quantitative risk assessment of dietary aflatoxin intake in maize, wheat, peanut and dairy products in relation to human hepatocellular carcinoma was carried out employing deterministic approach. Non-compliant samples’ proportions were calculated, and logistic regression and chi-square test used to compare different commodities. Animal feed were least compliant, with 64% and 39% having total aflatoxin (AFT) levels above Kenya and USA standards, respectively. Peanuts were the most non-compliant food, with 61% and 47% samples failing Kenya and USA AFT standards respectively, while wheat was least compliant (84%) according to EU threshold for AFT. Half of baby food sampled had AFT level above Kenya and EU standards. High non-compliance rate with Kenya, USA and EU regulatory thresholds with respect to seven different mycotoxins (summarized as “mycotoxins”), and also AFT and aflatoxin M1 alone in edible materials is reported. Significant non-compliance is reported for compound animal feed, peanuts, wheat, baby food, feed ingredients, herbal healthy drink, maize and fodder feed in that order. High levels of aflatoxin residues in animal feed and human food was also observed. Lifetime human consumption of wheat and maize leads to high additional risk for primary liver cancer, human hepatocellular carcinoma (HCC) associated with dietary aflatoxin, wheat and its products causing the highest disease burden. Subsequent implications and limitations of current food safety standards are discussed. Humans and animals in Kenya appear to be chronically exposed to mycotoxin hazards: this calls for surveillance and risk management. There is urgent need for enhanced and consistent surveillance of the dietary mycotoxin hazards observed in this study employing representative sampling plans. Regulation and future research need to focus on reliable analysis techniques, collection of data on toxicological effects of mycotoxins and food consumption pattern, and regulatory limits accordingly set and compliance enforced to protect vulnerable groups such as paediatric, geriatric and sick members of the society to reduce cancer burden in Kenya

Mycotoxin hazards in the Kenyan food and feed market-a retrospective study

Mycotoxins are toxic fungal metabolites naturally found in food and feed as contaminants. Animal feed and human food samples (n=1818) from three major Kenyan laboratories were categorized as compliant and non-compliant according to Kenya, America (USA) and Europe (EU) mycotoxin regulatory limits. Quantitative risk assessment of dietary aflatoxin intake in maize, wheat, peanut and dairy products in relation to human hepatocellular carcinoma was carried out employing deterministic approach. Non-compliant samples’ proportions were calculated, and logistic regression and chi-square test used to compare different commodities. Animal feed were least compliant, with 64% and 39% having total aflatoxin (AFT) levels above Kenya and USA standards, respectively. Peanuts were the most non-compliant food, with 61% and 47% samples failing Kenya and USA AFT standards respectively, while wheat was least compliant (84%) according to EU threshold for AFT. Half of baby food sampled had AFT level above Kenya and EU standards. High non-compliance rate with Kenya, USA and EU regulatory thresholds with respect to seven different mycotoxins (summarized as “mycotoxins”), and also AFT and aflatoxin M1 alone in edible materials is reported. Significant non-compliance is reported for compound animal feed, peanuts, wheat, baby food, feed ingredients, herbal healthy drink, maize and fodder feed in that order. High levels of aflatoxin residues in animal feed and human food was also observed. Lifetime human consumption of wheat and maize leads to high additional risk for primary liver cancer, human hepatocellular carcinoma (HCC) associated with dietary aflatoxin, wheat and its products causing the highest disease burden. Subsequent implications and limitations of current food safety standards are discussed. Humans and animals in Kenya appear to be chronically exposed to mycotoxin hazards: this calls for surveillance and risk management. There is urgent need for enhanced and consistent surveillance of the dietary mycotoxin hazards observed in this study employing representative sampling plans. Regulation and future research need to focus on reliable analysis techniques, collection of data on toxicological effects of mycotoxins and food consumption pattern, and regulatory limits accordingly set and compliance enforced to protect vulnerable groups such as paediatric, geriatric and sick members of the society to reduce cancer burden in Keny

Potato cyst nematodes: a new threat to potato production in east Africa

Open Access Journal; Published online: 25 May 2020Potato cyst nematodes (PCN), such as Globodera rostochiensis and Globodera pallida, are quarantine restricted pests of potato causing major yield and financial losses to farmers. G. rostochiensis was first reported from Kenya’s key potato growing area in 2015. We sought to determine the diversity, prevalence and distribution of PCN species across the country by conducting a country-wide survey between 2016 and 2018, which included a more focused, follow-up assessment in three key potato growing counties. A total of 1,348 soil samples were collected from 20 potato growing counties. Information regarding local potato farming practices, potato cultivar use, their diversity and availability was also recorded. PCN cysts were obtained from 968 samples (71.8%) in all the counties surveyed, with Nyandarua County recording the highest PCN field-incidence at 47.6%. The majority of PCN populations, 99.9%, were identified as G. rostochiensis, while G. pallida was recovered from just one field, in a mixed population with G. rostochiensis. Inconsistencies in PCR amplification efficiency was observed for G. rostochiensis using the recommended EPPO primers, compared with ITS primers AB28/TW81, indicating that this protocol cannot be entirely relied upon to effectively detect PCN. Egg density in Nyandarua County varied between 30.6 and 158.5 viable eggs/g soil, with an average egg viability of 78.9 ± 2.8% (min = 11.6%, max = 99.9%). The PCN-susceptible potato cultivar named Shangi was the most preferred and used by 65% of farmers due to its shorter dormancy and cooking time, while imported cultivars (Destiny, Jelly, Manitou, and Markies) with resistance to G. rostochiensis were used by 7.5% of farmers due to unavailability and/or limited access to seeds. Thus, most farmers preferred using their own farm-saved seeds as opposed to purchasing certified seeds. Establishing the distribution and prevalence of PCN and elucidating the local farming practices that could promote the spread of PCN is a necessary precursor to the implementation of any containment or management strategy in the country and ultimately across the region

Survey of urban mosquitoes species (Diptera: Culicidae) with focus on waste water channels as larval habitats in Nairobi industrial area, Kenya

Background: A cross sectional study to establish the levels of heavy metals and other potentially harmful elements (PHEs)present in samples obtained from selected open waste water channels in Nairobi industrial area (Kenya) was carried out. The waste water channels selected were those near the factories or those directly discharging from factories. The samples collected included mosquitoes (larvae and adults), waste water, green algae, and soil. Unmaintained open waste water channels are among the man made features that enhance the breeding of urban mosquitoes because they tend to have overgrown vegetation and trapped solid wastes which slow or inhibit the waste water flow. Different mosquito species have previously transmitted arboviruses including those responsible for dangerous fevers such as West Nile, Rift Valley, Zika, Dengue, Yellow, and Chikungunya among others in different parts of the world. The study area (Nairobi industrial area) neighbors several densely populated informal human settlements. This paper specifically reports on composition and distribution of mosquito species obtained from the study area.Methods: The fourth instars mosquito larvae were collected from waste water channels using the standard dipping method. Adult mosquitoes were trapped using the center for disease control and prevention (CDC) light traps. Purposive random sampling for mosquito adults and larvae was carried out in industrial premises and waste water channels respectively at seven locations. This involved selecting sampling sites from which mosquito samples were likely to be obtained. The mosquitoes were then microscopically identified using taxonomic keys for the Ethiopian and East African region.Results: Out of 2,926 adult mosquitoes trapped, 12 species were identified including Cx. pipiens (95%); Cx. Vansomereni (2.6%); Cx. zombaensis (1.4%); Cx. univittatus (0.34%); Cx. theileri (0.21%); Ae. aegpti (0.14%); An. maculipalpis (0.03%); An. squamosus (0.03%) and other culicid species (0.20%). Of these adult mosquitoes, 94% (2753/2926) were females and 6% (173/2926) were males giving a male: female ratio of 1: 16 when using CDC traps. Of the 4,679 mosquito larvae scooped from the waste water channels, 4 species were identified including Cx. pipiens (99.34%); Cx. vansomereni (0.51%); Toxorhynchites brevipalpis (0.13%) and Aedes mosquito (0.02%).Conclusion: The majority of mosquito species obtained were culicid, Culex pipiens for both adults and larvae. A few Anopheles and Aedes populations were obtained. Unmaintained open waste water channels seen\med to enhance the breeding of urban mosquitoes in the study area. The ecology of these mosquitoes should be studied further to enhance surveillance and controlin order to minimize the risk of mosquito borne viral infections or any other re-emerging mosquito-borne infections to the residents of Nairobi, in particular those living in the informal settlements near Nairobi industrial area, Kenya.Keywords: urban, mosquitoes, Culex pipiens, waste water, industrial area, NairobiAfr J Health Sci. 2017; 30(2):120-13

Modulation of LPS-Induced CD4+ T-Cell Activation and Apoptosis by Antioxidants in Untreated Asymptomatic HIV Infected Participants: An In Vitro Study

Persistent immune activation characterises HIV infection and is associated with depletion of CD4+ T-cells and increased risk of disease progression. Early loss of gut mucosal integrity results in the translocation of microbial products such as lipopolysaccharide (LPS) into the systemic circulation. This is an important source of on-going immune stimulation. The purpose of this study was to determine levels of CD4+ T-cell activation (%CD25 expression) and apoptosis (% annexin V/7-AAD) in asymptomatic, untreated HIV infection at baseline and after stimulation with LPS and incubation with or without vitamin C and N-acetylcysteine. LPS induced a significant ( < 0.03) increase in %CD25 expression, annexin V, and 7-AAD in HIV positive individuals. NAC in combination with vitamin C, significantly ( = 0.0018) reduced activation and early apoptosis of CD4+ T-cells to a greater degree than with either antioxidant alone. Certain combinations of antioxidants could be important in reducing the harmful effects of chronic immune activation and thereby limit CD4+ T-cell depletion. Importantly, we showed that CD4+ T-cells of the HIV positive group responded better to a combination of the antioxidants at this stage than those of the controls. Therefore, appropriate intervention at this asymptomatic stage could rescue the cells before repetitive activation results in the death of CD4+ T-cells

Epidemiological profile and clinico-pathological features of pediatric gynecological cancers at Moi Teaching & Referral Hospital, Kenya

Background: The main pediatric (0–18 years) gynecologic cancers include stromal carcinomas (juvenile granulosa cell tumors and Sertoli-Leydig cell tumors), genital rhabdomyosarcomas and ovarian germ cell. Outcomes depend on time of diagnosis, stage, tumor type and treatment which can have long-term effects on the reproductive career of these patients. This study seeks to analyze the trends in clinical-pathologic presentation, treatment and outcomes in the cases seen at our facility. This is the first paper identifying these cancers published from sub-Saharan Africa. Method: Retrospective review of clinico-pathologic profiles and treatment outcomes of pediatric gynecologic oncology patients managed at MTRH between 2010 and 2020. Data was abstracted from gynecologic oncology database and medical charts. Results: Records of 40 patients were analyzed. Most, (92.5%, 37/40) of the patients were between 10 and 18 years. Ovarian germ cell tumors were the leading histological diagnosis in 72.5% (29/40) of the patients; with dysgerminomas being the commonest subtype seen in 12 of the 37 patients (32.4%). The patients received platinum-based chemotherapy in 70% of cases (28/40). There were 14 deaths among the 40 patients (35%) Conclusion: Surgery remains the main stay of treatment and fertility-sparing surgery with or without adjuvant platinum-based chemotherapy are the standard of care with excellent prognosis following early detection and treatment initiation. LMICs face several challenges in access to quality care and that affects survival of these patients. Due to its commonality, ovarian germ cell cancers warrant a high index of suspicion amongst primary care providers attending to adnexal masses in this age group

Population immunity to pneumococcal serotypes in Kilifi, Kenya, before and 6 years after the introduction of PCV10 with a catch-up campaign: an observational study of cross-sectional serosurveys

Background In Kilifi (Kenya), a pneumococcal conjugate vaccine (PCV10) was introduced in 2011 in infants (aged <1 year, 3 + 0 schedule) with a catch-up campaign in children aged 1–4 years. We aimed to measure the effect of PCV10 on population immunity. Methods In this observational study, repeated cross-sectional serosurveys were conducted in independent random samples of 500 children younger than 15 years every 2 years between 2009 and 2017. During these surveys, blood samples were collected by venesection. Concentrations of anti-capsular IgGs against vaccine serotypes (VTs) 1, 4, 5, 6B, 7F, 9V, 14, 18C, 19F, and 23F, and against serotypes 6A and 19A, were assayed by ELISA. We plotted the geometric mean concentrations (GMCs) by birth year to visualise age-specific antibody profiles. In infants, IgG concentrations of 0·35 μg/mL or higher were considered protective. Findings Of 3673 volunteers approached, 2152 submitted samples for analysis across the five surveys. Vaccine introduction resulted in an increase in the proportion of young children with protective IgG concentrations, compared with before vaccine introduction (from 0–33% of infants with VT-specific levels over the correlate of protection in 2009, to 60–94% of infants in 2011). However, among those vaccinated in infancy, GMCs of all ten VTs had waned rapidly by the age of 1, but rose again later in childhood. GMCs among children aged 10–14 years were consistently high over time (eg, the range of GMCs across survey rounds were between 0·45 μg/mL and 1·00 μg/mL for VT 23F and between 2·00 μg/mL and 3·11 μg/mL for VT 19F). Interpretation PCV10 in a 3 + 0 schedule elicited protective IgG levels during infancy, when disease risk is high. The high antibody levels in children aged 10–14 years might indicate continued exposure to vaccine serotypes due to residual carriage or to memory responses to cross-reactive antigens. Despite rapid waning of IgG after vaccination, disease incidence among young children in this setting remains low, suggesting that lower thresholds of antibody, or other markers of immunity (eg, memory B cells), may be needed to assess population protection among children who have aged past infancy. Funding Gavi, the Vaccine Alliance; Wellcome Trust