Residents of Flint, Michigan have been dealing with lead in their drinking water and a spike in cases of Legionnaires’ disease in the two years since they began receiving water from the Flint River. At least 87 residents of Genesee County developed Legionnaires’ disease from June 2014 to November 2015, and 10 have died. Only six to 13 cases were reported in the previous four years.

Legionnaires’ disease is a respiratory bacterial infection that is generally spread through mist from a water source. It cannot be transmitted from one person to another. It produces symptoms that include fever, chills, and cough. According to the Centers for Disease Control and Prevention, 8,000 to 18,000 people are hospitalized with Legionnaires’ disease each year in the United States.

Flint is an economically depressed city with about 100,000 residents. It used to purchase water from Lake Huron through the city of Detroit but began to get water from the Flint River about two years ago. The state government decided to change the water source to save money. The water soon began to look, smell, and taste funny, and residents complained. The water had high levels of iron from the Flint River and lead from pipes.

Flint switched back to its previous water source in October. More time and effort will be required to make the water safe to drink again. Health officials are still recommending that residents of Flint use bottled water and water filters.

Governor Rick Snyder declared a state of emergency in Genesee County on January 5 because of the water crisis. He apologized for the state’s actions, including denying the problem existed and failing to use anti-corrosive treatments on water from the river that could have reduced iron levels.

Synder activated the Michigan National Guard on January 13 to help with the water crisis. They will distribute bottled water and water filters at fire stations and other public buildings. Red Cross volunteers will go door to door and distribute water, filters, and testing kits. FEMA has approved the governor’s request for assistance in coordinating with other federal agencies.

The increase in the number of cases of Legionnaires’ disease cannot be directly attributed to the change in water supply since not all of the people who contracted the illness were exposed to Flint River water. According to Dr. Mark Edwards, a researcher from Virginia Tech who studied Flint water, it would be nearly impossible to definitively link the water source to Legionnaires’ disease because that would require matching the strain of the disease to the strain in the water. He said there has been a spike in cases and there is a strong likelihood that it was caused by the water. He said this could be the first case of Legionnaires’ disease associated with lack of corrosion control.

The U.S. Attorney’s Office in Eastern Michigan is investigating the water crisis in Flint. A class-action lawsuit has been filed against Snyder, the state government, and the city of Flint.