NEW YORK (WABC) -- The city is seeing a rise in cases of human leptospirosis, a disease caused by rat urine, which if left untreated can cause kidney failure and liver damage.
Last year the city saw 24 cases of human leptospirosis - the highest number in a single year.
Six cases have been reported so far this year, the city's Department of Health and Mental Hygiene said in an April 12 health advisory.
That is compared to the last two decades, where there was an average of three cases per year.
Leptospirosis is spread by bacteria in the urine of infected Norway rats, also called brown rats, who dominate the rodent population in New York City.
Mayor Eric Adams says the city has been ahead of the curve with rat mitigation.
"We knew this was a real problem, we didn't wait for this rat urine problem," Adams said.
The city has four rat migration zones -- in Harlem, Grand Concourse in the Bronx, Bedford-Stuyvesant/Bushwick, and East Village/Chinatown.
Adams believes the city got ahead of the curve with the implementation of mandatory garbage bins -- helping to limit any skin exposure to rats.
"People need to connect the dots, plastic bags mean rodents, get the plastic bags off our streets, you will make a major dent in the rat mitigation problem," Adams said.
Adams said total success would be no more rats.
"I don't think any rodent can traumatize you any more than a rat," Adams said. "So success is to stop the traumatizing of people that the rodents have basically taken over our city."
In 2017, one person died and two others became severely ill from the disease in the Bronx. The cluster of cases was identified at an apartment building and was caused by a rat infestation and inadequate garbage management.
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