FLINT, MI - Health officials waited roughly a year and a half to notify Gov. Rick Snyder about spiking rates of Legionnaires' Disease in the Flint area, according to state authorities.

State Medical Executive Eden V. Wells said Thursday, Jan. 14, that state health officials typically do not brief the governor's office of ongoing investigations, but continuing issues surrounding the city's water supply spurred the state's health agency to release information prior to a formal report being released.

Health and Human Services Department Director Nick Lyon said during a Wednesday press conference with Snyder that his agency became aware of a spike in Legionnaires' cases around Flint in 2014.

"In the late summer of 2014, we began to see a spike in these cases and we let the local health department know," Lyon said. "We actually stepped in with them and started doing some of these investigations."

Six cases of Legionnaires' Disease were reported in Genesee County in June 2014, which was more than any other month since March 2010 and slightly less than the total number of cases reported in 2013, according to a June 2015 initial report on the outbreak released Wednesday by the Michigan Department of Health and Human Services.

Since June 2014, there have been 87 reported cases of Legionnaires' Disease, resulting in 10 deaths, around the Flint area.

The outbreak began just weeks after the city stopped using treated water from Detroit and began using the Flint River as the source of its drinking water, a change made by a Snyder-appointed emergency manager.

The change has drawn international attention after it resulted in elevated blood lead levels for some of the city's youngest residents and reports of smelly, discolored water from other community members.

Wells said the June 2015 report on the outbreak was initially shared with officials from the Genesee County Health Department and the Centers for Disease Control and Prevention, who were working to identify a source of the outbreak.

The report, which focused on 45 cases of Legionnaires' Disease reported between June 6, 2014, and March 9, 2015, explored each victim's potential connection to the Flint water system and Flint-based medical facilities.

A source of the outbreak has not yet been identified.

The June 2015 report showed all but 10 of the victims either had Flint drinking water at their residence or were at Flint medical facilities within two weeks of symptom onset.

A Thursday release from the Genesee County Health Department stated residents cannot become ill from drinking water containing the bacteria responsible for Legionnaires' Disease. The release stated is a waterborne disease, usually located in man-made water supplies that aerosolize water, such as showers, hot water tanks, humidifiers, cooling towers, whirlpool spas and decorative fountains.

Wells said studies continued into the outbreak when researchers observed a second outbreak of the disease. As health officials compiled data in December 2015, Wells said they decided to inform the governor of the problem.

Snyder said he was informed of the outbreak in the days leading up to Wednesday's press conference.

"The circumstances of these cases prompted the chief medical examiner and other leaders at the Department of Health and Human Services to brief the governor, and he decided to quickly make the information public," Snyder spokesman Dave Murray said.

Legionella, the bacteria that can lead to Legionnaires' Disease, tends to thrive in warm, stagnant water, Wells said. The bacteria occurs naturally, which can make tracking its source difficult for investigators.

"Legionella is a tough bacteria to investigate," Wells said.

Wells said a new report, which include cases from the summer of 2015, is expected to be released within a week.

However, investigators will continue working to identify the source and continue observing the Flint area as temperatures begin to warm in the spring, which could spell a return of the bacteria.

"You can bet there would be a lot of interest as it gets warmer," Wells said.