The water crisis in Flint, Michigan caused an outbreak of Legionnaires’ disease that killed 12 people and sickened nearly 90 others, according to a new report.
In April 2014, the city’s water source was switched from the Detroit water system to the Flint River.
This cost-cutting measure led to tainted drinking water that contained lead and other toxins.
New research published in the Proceedings of the National Academy of Sciences reveals the contaminated water also carried Legionella bacteria which triggered an outbreak.
Flint’s water crisis began when the city switched its water source in 2014. Since then, several residents have discovered high levels of lead in their blood stream
Legionnaires’ disease is a pneumonia-like lung infection that kills one out of 10 people, according to the Centers for Disease Control and Prevention.
People can contract the disease when they breathe in mist that contains contaminated with Legionella.
For the study researchers analyzed data on Legionnaires’ cases in Genesee, Wayne and Oakland Counties from 2011 to 2016.
They found that about 80 percent of Legionnaires’ cases during this period are caused by the change in water supply.
Researchers found that months after Flint’s water supply started coming from Flint River, people in that city were seven times more likely to be diagnosed with the respiratory disease.
‘After public announcements urging residents to boil their water, there was a lower risk of developing the disease, likely because people avoided using the water,’ said Dr Sammy Zahran, an associate professor of demography and epidemiology at Colorado State University.
The study also revealed that the risk of the disease was higher in neighborhoods with lower levels of free chlorine — a substance added to water systems for disinfection.
Dr Zahran, lead author of the study said Legionella bacteria are less likely to survive in water with high free chlorine levels.
However, high levels of iron and organic matter in corroding water pipes — an issue with older infrastructure — both feed Legionella and neutralize chlorine.
Researchers discovered that during the water crisis, the likelihood of Legionnaires’ disease occurring in communities adjacent to Flint also increased, probably due to the number of people who commuted into Flint.
Researchers reinforced that the outbreak was linked to the water change, by nothing that the Legionnaires’ disease risk returned to normal levels when the city went back to using the Detroit water system in 2015.
‘This is a big deal,’ Janet Stout, research associate professor of civil and environmental engineering at the University of Pittsburgh, who was not involved with the PNAS study, told BuzzFeed News.
‘The link to the impact of the water quality on the outbreak has been something that has never been seen before or explored in the level of depth as this investigation.’
On Monday, the Michigan Department of Health and Human Services said the study was innacurate.
‘By publishing these inaccurate, incomplete studies at this point, FACHEP has done nothing to help the citizens of Flint and has only added to the public confusion on this issue,’ Health and Human Services spokeswoman Geralyn Lasher said in a statement.
Most healthy people exposed to Legionella bacteria do not get sick.
However, those with an increased risk of becoming seriously ill include people 50 years or older, people with chronic lung disease, and people with weakened immune systems.