Short-Term Elevation of Fine Particulate Matter Air Pollution and Acute Lower Respiratory Infection

Nearly 60% of U.S. children live in counties with particulate matter less than or equal to 2.5 μm in aerodynamic diameter (PMTo evaluate the association between ambient PMUsing an observational case-crossover design, subjects (n = 146,397) were studied if they had an ALRI diagnosis and resided on Utah's Wasatch Front. PMApproximately 77% (n = 112,467) of subjects were 0-2 years of age. The odds of ALRI encounter for these young children increased within 1 week of elevated PMIn this large sample of urban/suburban patients, short-term exposure to elevated PM