The Virginia Department of Health (VDH) provided an update Friday on the outbreak of Shiga toxin-producing Escherichia coli (STEC) in people who were in the Lake Anna area on and after the Memorial Day weekend. To date, 25 STEC probable and confirmed cases have been reported to VDH: 21 in Virginia residents from the Central, Northern, and Northwest regions of the state and four in residents of other states. 

Most cases (76%) have occurred in children younger than 18 years of age. Severe STEC infections can progress to hemolytic uremic syndrome (HUS), which can be particularly serious. To date, five HUS cases have been reported to VDH, all in children who required hospitalization.   

VDH has been partnering with the Department of Environmental Quality (DEQ) in the collection of water samples at six priority locations in Lake Anna. There was an increase in STEC cases in the Rappahannock Health District during the first week of June. Soon after, the Office of Environmental Health Services initiated an investigation and began tracking the results. The first sampling occurred on June 11, and the second is planned for June 17. 

Water column samples were analyzed for bacteria, including E. coli, by the Department of General Services Division of Consolidated Laboratory Services (DCLS), the state laboratory. Results for samples collected June 11 indicate all fecal bacteria concentrations were well below a public health level of concern. A map of the six sampled areas and the test results is available on the VDH outbreak website, launched today.  

VDH’s investigation is ongoing. No single cause of the outbreak has been identified, and it is possible we might not be able to identify the source. There is no indication that contaminated food was the source of the outbreak. Environmental pollution from heavy rains, livestock, failing septic systems, boating discharge, and swimmers are potential sources of illness when swimming in natural waters. Avoid swimming where livestock are present. 

If you were in the Lake Anna area on Memorial Day weekend or since and you experienced gastrointestinal illness (such as stomach cramps and diarrhea), contact your local health department and seek medical care if you are still experiencing symptoms. 

To prevent illness when swimming and boating in natural waters, people should: 

  • Never drink untreated water, and don’t swim if skin has cuts or open wounds. Natural waters such as rivers, lakes, and oceans contain germs and contaminants, which can cause illness. 
  • Wash their hands after using the bathroom and before preparing and eating food. 
  • Avoid swimming near storm drains (pipes that drain polluted water from streets). 
  • Avoid swimming if they are vomiting or have diarrhea. 
  • Avoid going in water if there is a green film on the water and keep pets out as well. This may indicate an algal bloom and some algae produce toxins that can make people sick. 
  • Shower or bathe after swimming to wash off possible germs and contaminants. 
  • Avoid swimming for three days after a heavy rain. Germs can come from overflowing sewage, polluted storm water & runoff from land. 
  • Properly dispose of human waste by discharging boat sewage at marinas with a pump-out unit or dump station.  
  • If your body’s ability to fight germs is already affected by other health problems or medicines, check with your healthcare provider before swimming in oceans, lakes, rivers, and other natural bodies of water.