FLINT, Michigan -- Michigan health authorities reported they have identified two more fatal cases of Legionnaires' disease in the Flint area last year amid an outbreak some outside experts have linked to the city's water emergency.
The additional 2015 deaths are among 12 detected in Genesee County over a 17-month period.
In an updated analysis, the state Department of Health and Human Services raised the total number of cases by three to 91, a five-fold increase over what the county averaged before the city switched to using the Flint River as its water source in 2014 while under state financial management.
In October, the impoverished city of nearly 100,000 people returned to using Lake Huron water treated by Detroit's system after elevated lead levels were found in some children.
State environmental regulators had incorrectly told Flint officials not to add anti-corrosion chemicals to the river water, which let lead from old pipes leach into homes. Residents now are using faucet filters or bottled water.
Legionnaires' disease is a pneumonia caused by bacteria in the lungs.
People get sick if they inhale mist or vapor from contaminated water systems, hot tubs or cooling systems - typically in large buildings such as hospitals and hotels.
Of the 91 confirmed cases, 50 were linked to a Flint hospital served by the municipal water system.
During the outbreak, McLaren Flint spent more than $300,000 on a water treatment system, banned showers and also turned to bottled water for patients. A message seeking comment was left Monday for a McLaren spokeswoman.
The state again said it can neither conclude that the surge in Legionnaires' cases is related to the water switch, nor rule it out.
"We remain vigilant in identifying any potential case associated with the outbreak," said Dr. Eden Wells, Michigan's chief medical executive.
The health agency said it identified the new cases from testing data recently forwarded along by the hospital.
Two cases had not been appropriately reported, according to the department, while a third was reported in a different jurisdiction and there was no epidemiologic information available to link it to the outbreak.
A task force appointed by Republican Gov. Rick Snyder, who has apologized for the crisis, concluded last month that communication and coordination between the MDHHS and the Genesee County Health Department regarding Legionellosis cases were "inadequate to address the grave nature of this outbreak," particularly because the cases occurred at a time when there were several other concerns about Flint's water.
It faulted health officials for not alerting the medical community or the public and criticized the state Department of Environmental Quality for not notifying the governor's office with "sufficient urgency."
After an initial wave of 45 cases from June 2014 through March 2015, state epidemiologists declared last May that the outbreak was "over" only to confirm 46 more cases between that month and October.
The governor publicly disclosed the spike in cases in January, saying he had just been informed.
Some of his staff members, though, had been told about the surge and a possible connection to the river in January and March of 2015.
After being briefed on an internal review of his health department, Snyder last month called for an investigation by Michigan's auditor general and the health agency's inspector general.
MDHHS Director Nick Lyon is scheduled to testify about the crisis before the U.S. House Energy and Commerce Committee on Wednesday.
State Senate Minority Leader Jim Ananich, D-Flint, criticized the Snyder administration for discovering the additional deaths "months after the fact."
"Based on that track record, I'm not confident the Department of Health and Human Services can handle another outbreak," he said, "never mind this one."
Michigan finds 2 more Legionnaires' deaths in Flint area