AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Quantitative Microbial Exposure Assessment of Aerosolized Enteric and Opportunistic Pathogens in La Paz, Bolivia: A One Health Approach to Study Bioaerosols in Cities with Poor Sanitation
LUCAS ROCHA-MELOGNO, Olivia Ginn, Emily Bailey, Gregory Gray, Michael Bergin, Freddy Soria, Marcos Andrade, Joseph Brown, Marc Deshusses, Duke University
Abstract Number: 288 Working Group: Bioaerosols
Abstract In an increasingly urbanized world, many cities in developing countries have little to no safely managed sanitation services. Their citizens consequently are exposed to a variety of fecal pathogens through various pathways, posing significant human health risks. Cities with open sewers are of particular interest to us because we hypothesize that aerosolized fecal pathogens pose a risk of infection in such contexts, potentially creating lifetime health deficits. The goal of our field study was to explore two exposure pathways in an environment where harmful and opportunistic bioaerosols may be prevalent.
The city of La Paz in Bolivia extends in a canyon with poor urban planning and discharges its industrial wastewater, hospital and domestic sewage into the Choqueyapu River. We conducted passive and active bioaerosol sampling at multiple sites next and at <5 km away from the Choqueyapu River hypothesized to be a source of bioaerosols during the rainy and dry season in 2019. We took minute-interval measurements of wind speed, temperature, relative humidity, UV index and PM2.5 (using low-cost sensors) to evaluate their impact in the bioaerosols fate and transport. Molecular analyses were conducted on samples brought back to the US using RT-PCR and dd-PCR to identify and quantify gene abundance of pathogens of interest. During the rainy season, an average airborne concentration of 53 total coliform (TC) CFU/m3 was found, with up to 19% of them being viable E. coli. Settle-plate fluxes averaged 130 TC CFU/m2/h and only one E. coli CFU was observed (n=60 plates). Distance from the Choqueyapu River did not have an effect on the CFU fluxes observed throughout the city except in one site. In this talk, detailed findings and exposure analyses combining our expertise in microbiology, air pollution and epidemiology will be presented.