Surveillance Reports for Outbreaks Associated with Environmental & Undetermined Exposures to Water

CDC publishes summaries of outbreaks associated with environmental and undetermined exposures to water in the United States based on reports provided by state, local, and territorial health departments. These summaries help public health practitioners better understand the germs, settings, and contributing factors (for example, water was not disinfected properly) involved in outbreaks linked to environmental exposures. They also can help identify emerging waterborne disease threats and be used to inform and assess outbreak prevention measures.

Since 1971, CDC has published data on waterborne disease outbreaks associated with environmental and undetermined exposures to water:

• 2015 forward: Reports are published on CDC’s Summary Reports of Waterborne Outbreaks page.
• 2011–2014: Reports were published in the MMWR Weekly with supplemental content posted on this website.
• 1971–2010: Data on outbreaks in this category were previously published as outbreaks associated with “other non-recreational water,” “water not intended for drinking,” and “water of unknown intent.” Links to surveillance reports with these data are available on the Surveillance Reports for Drinking Water–associated Disease and Outbreaks

You can also explore waterborne disease outbreak data starting in 1971 on CDC’s National Outbreak Reporting System Dashboard.

Learn more about waterborne disease and outbreak surveillance milestones.