Outbreaks related to drinking water caused more than 1,000 illnesses

There were 33 disease outbreaks associated with drinking water from 2009 to 2010 that resulted in 1,040 cases of illnesses, 85 hospitalizations and nine deaths, according to data published by the CDC and the Environmental Protection Agency.

“As observed in recent years, the proportion of outbreaks in the federally regulated portions of public water systems has declined, although these still contribute to the majority of outbreak-associated illnesses,” the researchers wrote in Morbidity and Mortality Weekly Report. “Deficiencies at points not under the jurisdiction of water utilities (eg, private wells and plumbing systems) continue to cause illness.”

From 2009 to 2010, the most recent years that have finalized data available, there were 33 drinking water outbreaks reported by health officials from 17 states. All but one outbreak had at least one etiologic agent identified. The most common was Legionella, which caused 58% of the outbreaks, followed by Campylobacter, which caused 12% of the outbreaks. However, Campylobacter caused more illness. It was responsible for 78% of the illnesses compared with Legionella, which was responsible for 7%.

Most of the outbreaks and illnesses were linked to community water systems, which serve year-round residents of a community, subdivision or mobile park home. Legionella in plumbing systems was the most common outbreak deficiency, followed by untreated ground water and distribution deficiencies. Most outbreaks involved acute respiratory illness, but the most common outbreak-associated illness was acute gastrointestinal illness.

“Partnerships between state and local public health agencies, as well as cooperation and coordination among epidemiologists, laboratorians and environmental health specialists within agencies, are needed to optimize investigation and reporting of waterborne disease outbreaks,” the researchers wrote.

Disclosure: The researchers report no relevant financial disclosures.