Inactivation of Legionella pneumophila harbored by amoebae using a nano-enabled alternative technology: Application and outreach to the Colonias in Texas

University Of Texas At Austin, Austin TX

Investigators

Abstract

Legionnaires' disease is a deadly form of pneumonia caused by the bacterial pathogen Legionella pneumophila. Several outbreaks of this waterborne disease have occurred in the U.S. since 1976, and new cases have been growing at a high rate. Exposure occurs when contaminated water droplets are inhaled (e.g., during showering) or aspirated. L. pneumophila can be harbored by free-living single-celled organisms (amoebae), which can shield L. pneumophila from traditional disinfection like a 'Trojan horse', thereby increasing risk for the spread of Legionnaires' disease. This project aims to develop a low-cost disinfection technology that can harness low-energy microwave radiation to inactivate L. pneumophila in drinking water. The work includes a major outreach program with the Texas colonias, or self-built communities, which are home to 400,000 low-income people, many of whom lack access to high quality drinking water. Successful development of this technology has the potential to ensure safe drinking water for the colonias and the Nation. The goal of the proposed irradiation-based technology is to generate interfacial heat and reactive oxygen species (ROS) to inactivate L. pneumophila harbored by amoebae. Amoebae will be lysed via interfacial heating, and the released L. pneumophila will be inactivated by heat and ROS. The proposed research will deploy fundamental nanoscience to develop a point-of-use (POU) and community-scale water treatment technology. The specific technical objectives of the proposed research plan are to (i) synthesize, characterize, and test MW-harnessing nanomaterials, (ii) understand the mechanisms of microbial inactivation by this MW-based nanotechnology, and (iii) engineer two devices containing immobilized nanomaterials to effectively inactivate L. pneumophila harbored by amoebae. The research will capitalize on the scientific advantages of novel MW spectral conversion to provide safe drinking water to low-income residents of the Texas colonias and beyond. Outreach activities will occur in elementary schools and colonias located in three school districts (two in El Paso County and one in Hidalgo County, both of which have high concentrations of colonias). Hands-on educational activities related to the research will be conducted in the schools, and water sampling and household surveys will be conducted in the colonias to gather information on water quality, water use, water-related health issues, and socioeconomic conditions. The outreach is unique because the information it yields will be utilized in the device design, thereby enabling the development of a socially-embedded technology. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.