Occupation, Socioeconomic Status Tied to Legionellosis Risk

Where you live and where you work can increase your risk of getting Legionnaires' disease.

Andrea Farnham, MPH, a research scientist with the Immunization Surveillance Team at the New York City Department of Health and Mental Hygiene, and colleagues analyzed federal and New York City data to identify epidemiological risk factors in cases of the aerosolized waterborne, pneumonia-like bacterial infection from 2002 to 2011. In a study published online October 15 and in the November 2014 issue of Emerging Infectious Diseases, the authors report that new cases in New York City rose by 230% from 2002 to 2009.

The authors acknowledge several study limitations, including the general underdiagnosis of legionellosis, the lack of racial/ethic data for almost 20% of their cases, and the low, 30% proportion of cases who reported having worked in the last 2 weeks. They made several recommendations, however, to public heath authorities.

The increase in New York City appears to parallel that seen nationally, the authors note. Data from the Centers for Disease Control and Prevention indicate that 8000 to 18,000 people in the United States are hospitalized for Legionnaires' disease annually and that 5% to 30% of cases are fatal. From 2000 to 2011, the national incidence increased by 249%, going from 0.39 cases per 100,000 population in 2000 to 1.36 cases in 2011. However, the number of cases is likely underreported.