Michigan sees increase in Legionnaire’s disease – Macomb Daily

Macomb County has 15 confirmed cases of Legionnaires’ disease in what the Michigan Department of Health and Human Services sees as a statewide jump.

Between July 1 and July 14, 107 cases of Legionnaires’ disease were reported in 25 counties. Although the increase in the number of cases is often linked to environmental factors, including heat and precipitation, this represents an increase of 569% from the benchmarks for the same period in 2020 (16 cases) and an increase of 161 % compared to references for the same period in 2019 (41 cases). Confirmed cases include 19 in Wayne County, 17 each in Oakland County and the city of Detroit, and 15 in Macomb County.

The MDHHS is coordinating with local state health departments to investigate a recent increase in reports of Legionnaires’ disease.

The Legionella bacteria cause two forms of respiratory infections of Legionellosis. Legionnaires’ disease is an infection whose symptoms include fever, cough, and pneumonia. A milder form of Legionellosis, Pontiac fever, is a flu-like illness without pneumonia that resolves on its own.

Andrew Cox, director / health official for the Macomb County Health Department, said the 15 cases in Macomb County have yet to be linked to one or more specific causes. But in general, Cox believes that there are three factors that lead to an increase in cases of Legionnaires’ disease.

• First, Cox said, choosing not to wear a mask during the COVID-19 pandemic could lead to contracting the disease. Like COVID-19, Legionnaires’ disease is a respiratory illness. Not only does wearing a mask reduce the likelihood of contracting the coronavirus, it could also reduce the number of Legionnaires.
• The second is the number of buildings that have slept during the COVID-19 pandemic. When people return to their workplaces that have not been used for about 18 months, they are returning to buildings where the water from plumbing systems or cooling systems is stagnant and may contain bacteria. Even in a typical summer before COVID-19, cooling towers and air conditioning units can be places where Legionella bacteria can thrive. Legionella bacteria are found naturally in lakes and freshwater streams, but can also be found in man-made water supply systems. Drinking water systems, cooling towers, hot tubs, and decorative fountains provide common environments for bacterial growth and transmission if not cleaned and maintained properly. Hot water, stagnation, and low sanitizer levels are conditions that promote the growth of these water systems.
• Third, the huge collection of precipitation that the state of Michigan, and particularly southeastern Michigan, has experienced so far this spring and early summer could be contributing to the increase in the number of Legionnaires. . Frequent storms with high volumes have left many places with standing water that could grow bacteria and develop armyworms for those who come in contact with it.

The MDHHS and local health services are working to inform health care providers of the increase in cases and to share information regarding testing and treatment. While cases of Legionella are more common in summer and early fall during warming, standing water presents the best environment for bacterial growth in aquatic systems, this increase is higher than expected for Michigan for this. period of the year. The MDHHS asks providers to keep this in mind with patients presenting for care with pneumonia and existing risk factors for this infection. To date, no common source of infection has been identified.

“Recent weather trends, including rain, flooding and warmer weather, could play a role in the increase in reported cases of Legionnaires’ disease this summer,” added Dr Joneigh Khaldun, MDHHS medical director and deputy director in chief of health. “We want everyone to know about Legionnaires’ disease, especially if they have a higher risk of disease, and we ask healthcare providers to remain vigilant, test and treat appropriately. “

Transmission occurs when a mist or vapor containing the bacteria is inhaled. Legionnaires’ disease is not spread from person to person. Risk factors for exposure to Legionella bacteria include: recent overnight travel; a recent stay in a health establishment; exposure to hot tubs; exposure to areas where plumbing has undergone recent repairs or maintenance.

Most healthy individuals are not infected after exposure to Legionella. Those most at risk of getting sick include people who are already compromised in some way. The most sensitive people are people over 50; current or former smokers; people with chronic lung disease; those whose immune system is weakened by diseases such as cancer, diabetes or liver or kidney failure; and those taking immunosuppressive drugs.

Cox said the cases in Macomb County cannot yet be considered an outbreak because there has not been a link to a certain group or exposure that has been established. But he said he expects more cases to occur in July, August and through September. Typically, the number of cases decreases as the weather cools in October.

People with concerns about Legionnaires’ disease or exposure to Legionella bacteria should speak to their health care provider. The MDHHS and local health services will continue to monitor cases and provide updates to the public. More information on Legionella and Legionnaires’ disease is available on the Centers for Disease Control and Prevention website.