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bioRxiv · 10.1101/493213

Enteric Pathogen Diversity in Infant Foods in Low-income Neighborhoods Of Kisumu, Kenya

Abstract

Pediatric diarrheal disease remains the 2nd most common cause of preventable illness and death among children under the age of five, especially in Low and Middle-Income Countries (LMICs). However, there is limited information regarding the role of food in pathogen transmission due to measuring infant food contaminations in LMICs. For this study, we examined the frequency of enteric pathogen occurrence and co-occurrence in 127 weaning infant foods in Kisumu, Kenya using a multi-pathogen rt-PCR diagnostic tool, and assessed household food hygiene risk factors for contamination. Bacterial, viral, and protozoa enteric pathogen DNA and RNA were detected in 62% of the infant weaning food samples collected, with 37% of foods containing more than one pathogen type. Multivariable generalized linear mixed model analysis indicated type of infant food best explained the presence and diversity of enteric pathogens in infant food, while most household food hygiene risk factors considered in this study were not significantly associated with pathogen contamination. Specifically, cows milk was significantly more likely to contain a pathogen (adjusted Risk Ratio=14.4; 95% Confidence Interval (CI) 1.78-116.1) and contained 2.35 more types of pathogens (adjusted Risk Ratio=2.35; 95% CI 1.67-3.29) than porridge. Our study demonstrates that infants in this low-income urban setting are frequently exposed to diarrhoeagenic pathogens in food and suggests that interventions are needed to prevent foodborne transmission of pathogens to infants.\n\nImportanceFood is acknowledged as an important pathway for enteric pathogen infection in young children. Yet, information on enteric pathogen contamination in food in low-and-middle income settings is lacking, especially with respect to weaning foods given to young infants. This study assessed which food-related risk factors were associated with increased presence of and diversity in twenty-seven types of enteric pathogens in a variety of foods provided to infants between three and nine months of age in a low-income neighborhood of Kisumu, Kenya. Feeding infants cow milk emerged as the most important risk factor for food contamination by one or more enteric pathogens. The results indicate public health interventions should focus on improving cow milk safety to prevent foodborne pathogen transmission to infants. However, more research is needed to determine whether infant milk contamination was caused by caregiver hygiene practices versus food contamination passed from upstream sources.

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Tsai, K., Simiyu, S., Mumma, J., Aseyo, R. E., Cumming, O., Dreibelbis, R., Baker, K.. 2018-12-11. Enteric Pathogen Diversity in Infant Foods in Low-income Neighborhoods Of Kisumu, Kenya. https://doi.org/10.1101/493213

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