The Minnesota Department of Health (MDH) announced today that it has identified the likely source of the Legionnaires’ Disease outbreak in Hopkins. A set of cooling towers at Citrus Systems, Inc., at 415 11th Avenue South in Hopkins tested positive for the pathogenic bacteria.
Test results of water samples taken from Citrus System’s cooling towers showed the outbreak strain of bacteria. The bacteria matched the strain of bacteria taken from patients sickened in this outbreak. Other cooling towers in the area were sampled, but none of them had the outbreak strain of Legionella.
Twenty-three people have been sickened in this outbreak. Of those patients, 17 were hospitalized. One person died. The last date that an illness was reported was on September 22, 2016, almost three weeks ago. There have not been any more reported cases since that date.
MDH Deputy State Epidemiologist Richard Danila said in a statement, “the lab testing is highly specific and provides us with great confidence that this tower is the source of infection.” He also spoke about the likelihood of seeing more cases. “Although it’s been more than 14 days since the tower was sanitized and since our last case, which is beyond the typical 10-day incubation period for Legionella, it’s still possible we could see an additional case if someone were exposed on September 27, 2016. It often takes time for cases to present for care and to be tested. However, we believe the source has been identified and remediation has occurred.
Citrus Systems is working with MDH to make sure that the problem has been solved and their system is working correctly. Part of a remediation plan should include retesting the cooling tower and water systems so if any bacteria are still present they can be destroyed. The company has a management plan in place.
Public health officials recommend that all building managers and owners in Minnesota develop a water management program for their cooling towers. Contamination of these structures, as well as plumbing systems in older buildings, can easily occur. The water in cooling towers is usually heated by moving air through a recirculated system, which creates the ideal environment and water temperature for the growth of Legionella bacteria. These fans create a lot of water vapor, which is the typical mode of infection.
People get Legionnaires’ Disease by breathing in water vapor that contains the bacteria. Most patients are over the age of 50, current or former smokers, or those with compromised immune systems or lung disease. The illness begins 2 to 10 days after exposure.
The symptoms of Legionnaires’ Disease, which is a type of pneumonia, begin gradually. The first symptoms may include headache, chills, a high fever, and muscle aches. By the second or third day, a cough will develop, which may produce blood and mucus, along with chest pain, shortness of breath, and possible nausea, vomiting, and diarrhea. This illness is often diagnosed as ordinary pneumonia at first. Then, when more people start presenting with the same symptoms, doctors will test for Legionnaires Disease.
If you live or work in the Hopkins, Minnesota area and have experienced these symptoms, see your doctor. Quick treatment is essential for a good outcome. Unfortunately, Legionnaires has a 5 to 30% mortality rate.
