In his email to Hollins, Wurfel said that there had been 40 Legionnaires cases in Genesee County since April 2014, “more than all the cases in the last five years combined.”

The spokesperson sent him of a memo by Genesee County health official Jim Henry, who had alerted the DEQ to a “significant increase of confirmed Legionella illnesses” on March 10, 2015.

On March 13, 2015, Harvey Hollins, a top adviser to Gov. Rick Snyder — who oversees the Office of Urban and Metropolitan Planning Initiatives — received an email from Michigan Department of Environmental Quality (DEQ) spokesperson Brad Wurfel.

The emails were received 10 months before Gov. Rick Snyder alerted the public to lead contamination in Flint's water, brought on after the source was changed from Detroit's system to the Flint River.

Emails made public Wednesday show that a Michigan state official knew about a reported significant increase in Legionnaires’ disease in Genesee County possibly connected to Flint’s contaminated water.

Michigan Gov. Rick Snyder talks about the status of the water crisis on Jan. 27, 2016 at Flint City Hall.

April 2014 was the same month and year that the city of Flint, headed by a state-appointed emergency manager, approved the water source switch.

Henry had written in a March 10 email to members of the DEQ that he believed the “increase of the illnesses closely corresponds with the timeframe of the switch to Flint River water.”

Legionnaires is a water-borne respiratory disease with pneumonia-like symptoms, according to the CDC. Most people are exposed to it through vaporized water in warmer climates, making it especially prevalent in nursing homes and assisted care facilities.

“Untreated,” Wurfel wrote, “it can be deadly.”

But Wurfel went on to call Henry’s declaration “beyond irresponsible,” and cited the fact that Henry’s department failed to conduct the necessary examinations to determine the source of the Legionnaires outbreak.

A separate internal email among several DEQ officials on March 12, 2015 called Henry’s position “premature and prejudice” because it lacked further investigation.

“It is highly unlikely that legionella would be present in treated water coming from the City of Flint water treatment plant,” the email read.

A spokesman for the governor on Thursday said Hollins or others did not pass on information to Snyder until January 2016, at which point he took action and released information to the public.

"When Harvey Hollins received the March email, he requested the DEQ look into the concerns, check with its experts, and get the facts. If the concerns were determined to be credible, the director was to bring the issue to the attention of the Governor.

"The issue was not brought to the Governor’s attention until January of this year. Gov. Snyder has made changes at the department to address these concerns and change the culture to best protect the well-being of Michiganders."

The city of Flint is currently mired in a water contamination crisis that has left some of its most vulnerable residents with high levels of lead in their blood. State officials have faced heavy criticism for a delayed response to the situation, and some have been called to testify before Congress.

Read the unsealed emails here.