Waterborne Illness Surveillance Statistics

Epidemiologists at the Minnesota Department of Health conduct surveillance and epidemiologic studies to track waterborne diseases and identify waterborne disease outbreaks in Minnesota.

Waterborne Illness Outbreaks

Drinking water outbreaks

From 2009 to 2018 there were five reported drinking water illness outbreaks in Minnesota resulting in 20 known illnesses. Three were outbreaks of Legionnaires' disease associated with exposure to aerosolized water from building premise plumbing systems. One was an outbreak of giardiasis associated with drinking well water at a campground, and one was an outbreak of copper poisoning associated with a drinking fountain at a school.

Recreational water outbreaks

From 2009 to 2018 there were 56 reported recreational water illness outbreaks in Minnesota resulting in 731 known illnesses. More than half (52%) of the outbreaks were caused by Cryptosporidium. Other agents associated with outbreaks were: E. coli O157, Legionella, norovirus, Pseudomonas, Giardia, and chemicals. Of these 56 waterborne outbreaks, the most common type of illness experienced was acute gastrointestinal illness, reported in 35 (63%) outbreaks, followed by dermatitis reported in 12 (21%) outbreaks, and acute respiratory illness reported in 8 (14%) outbreaks. Outbreaks occurred in a variety of settings; 32 occurred in swimming pools, 9 in lakes and rivers, 9 in spa pools, 3 in splash pads, 1 in a swimming pond, 1 in an inflatable kiddie pool, and 1 in a man-made pond.

Other water outbreaks

From 2009 to 2018 there were six reported outbreaks in Minnesota associated with other types of water resulting in 46 known illnesses. Three were outbreaks of Legionnaires' disease; these outbreaks were associated with exposure to a decorative water wall in a casino, exposure to a cooling tower, and an unknown exposure at a senior living facility. The other three were outbreaks of giardiasis; all of these outbreaks were associated with drinking surface water along a hiking trail.

Charts, graphs, and maps

	Recreational Water Illness Outbreaks in Minnesota by County, 2009-2018 (PDF) Map showing the location of reported recreational waterborne illness outbreaks in Minnesota by county.
	Recreational Water Illness Outbreaks in Minnesota by Illness Type, 2009-2018 (PDF) Bar chart showing the number of recreational waterborne illness outbreaks by type of illness.

Disease-specific statistics

• Cryptosporidiosis statistics
  
  
• Giardiasis statistics

More Minnesota Waterborne Illness Statistics

• Disease Control Newsletter Annual Summaries
  Annual summaries of surveillance data for diseases and conditions reportable to the Minnesota Department of Health.
  
  
• Summary of Gastroenteritis Outbreaks in Minnesota
  Summary of gastroenteritis outbreaks in Minnesota that is published each year. Outbreaks summarized include those from food, water, animal contact, and person-to-person transmission.