Mumma, J. | bioRxiv Science

bioRxiv2018

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

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.

microbiology↗

bioRxiv2018

The Landscape of Enteric Pathogen Exposure of Young Children in Public Domains of Low-Income, Urban Kenya: The Influence of Exposure Pathway and Spatial Range of Play on Multi-Pathogen Exposure Risks

BackgroundYoung children are infected by a diverse variety of enteric pathogens in low-income, high-burden countries. Little is known about which conditions pose the greatest risk for enteric pathogen exposure and infection. Young children frequently play in residential public areas around their household, including areas contaminated by human and animal feces, suggesting these exposures are particularly hazardous.\n\nObjectivesThe objective of this study was to examine how the dose of six types of common enteric pathogens, and the probability of exposure to one or multiple enteric pathogens for young children playing at public play areas in Kisumu, Kenya is influenced by the type and frequency of child play behaviors that result in ingestion of soil or surface water, as well as by spatial variability in the number of public areas children are exposed to in their neighborhood.\n\nMethodsA Bayesian framework was employed to obtain the posterior distribution of pathogen doses for a certain number of contacts. First, a multivariate random effects tobit model was used to obtain the posterior distribution of pathogen concentrations, and their interdependencies, in soil and surface water, based upon empirical data of enteric pathogen contamination in three neighborhoods of Kisumu. Then, exposure doses were estimated using behavioral contact parameters from previous studies, and contrasted under different exposure conditions.\n\nResultsMulti-pathogen exposure of children at public play areas was common. Pathogen doses and the probability of multi-pathogen ingestion increased with: higher frequency of environmental contact, especially for surface water; larger volume of soil or water ingested; and with play at multiple sites in the neighborhood versus single site play.\n\nDiscussionChild contact with surface water and soil at public play areas in their neighborhood is an important cause of exposure to enteric pathogens in Kisumu, and behavioral, environmental, and spatial conditions are determinants of exposure.

microbiology↗