Nasopharyngeal Pneumococcal Density Is Associated With Viral Activity but Not With Use of Improved Stoves Among Young Andean Children.

• Type of Material: Article
• Authors: Leigh M Howard, Vanderbilt University Medical Center; Roger Fan, Vanderbilt University; Yuwei Zhu, Vanderbilt University; Marie R Griffin, Vanderbilt University; Kathryn M Edwards, Vanderbilt Vaccine Research Program; Stella Hartinger, Swiss Tropical and Public Health Institute; John V Williams, University of Pittsburgh; Jorge E Vidal, Emory University; Keith Klugman, Emory University; Ana I Gil, Instituto de Investigacion Nutricional; Claudio F Lanata, Instituto de Investigacion Nutricional; Carlos G Grijalva, Vanderbilt University
• Language: English
• Date: 2017
• Publisher: Oxford University Press
• Publication Version: Final Published Version
• Copyright Statement: © 2017, Oxford University Press
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1093/ofid/ofx161
• Title of Journal or Parent Work: Open Forum Infectious Diseases
• ISSN: 2328-8957
• Volume: 4
• Issue: 3
• Start Page: ofx161
• End Page: ofx161
• Grant/Funding Information: This work was funded by the Vanderbilt University Clinical and Translational Science Award (grant number UL1 RR024975-01) from the National Institutes of Health; investigator-initiated research grants (grant numbers IIR WS1898786 [0887X1-4492] and IIR WS2079099) from Pfizer; a grant from the Thrasher Research Fund (grant number 02832-9); and Vanderbilt University Medical Center Department of Pediatrics Turner-Hazinski and Katherine Dodd Faculty Scholars Awards.
• Keywords: pneumococcal density; pneumococcus; respiratory viruses; indoor smoke exposure
• Research Categories: Health Sciences, Medicine and Surgery; Health Sciences, Public Health

Abstract

BACKGROUND: Indoor smoke exposure is common in developing countries and may influence nasopharyngeal (NP) pneumococcal colonization density and risk of acute respiratory illness. We compared colonization density among Andean children living in households previously enrolled in a randomized controlled trial of a home intervention package including improved stoves to reduce smoke, kitchen sinks, and water disinfection. METHODS: We enrolled 260 children aged <3 years and made weekly household visits to assess for acute respiratory illness (ARI) and collect nasal swabs for respiratory virus polymerase chain reaction (PCR) testing during ARI. At monthly intervals, NP swabs were collected to determine pneumococcal colonization density through quantitative lytA PCR. We used linear quantile mixed-effects models to compare median log-transformed colonization densities among children in households randomized to the control (n = 129) versus intervention (n = 131) in sequential time points, accounting for random effects of multiple samples from individual children. Other covariates included age, sex, month, antibiotic exposure, and timing of sample collection relative to ARI with and without viral detection. RESULTS: Age and sociodemographic characteristics were similar between groups. Although no differences were observed in densities between groups, colonization density varied significantly over time in both groups, with highest densities coinciding with spring months. Time during and after virus-associated ARI was also associated with higher pneumococcal colonization density than time remote from ARIs. CONCLUSIONS: A home intervention package, including improved stoves, was not associated with changes in pneumococcal densities in young Andean children. However, increasing pneumococcal density was observed with spring season and viral-associated ARIs.