The New York Department of Health and Mental Hygiene issued a health advisory following a rise in reported cases of human leptospirosis in New York City.
Leptospirosis is an infection linked to exposure to rat urine.
In 2023, the city recorded 24 cases of leptospirosis, the highest number in any previous year. However, in the first quarter of this year alone, there have already been six reported cases.
“For comparison, the average number of locally acquired cases during 2021 to 2023 was 15 per year, and 3 cases per year during 2001 to 2020,” health officials said. “This year, 6 cases have been reported as of April 10, 2024.”
“Among the 98 locally acquired cases reported from 2001 to 2023, the median case age was 50 years (range 20 to 80 years), usually male (94%) and, reported most often from the Bronx (37), followed by Brooklyn (19), Manhattan (28), Queens (10), and Staten Island (4),” said the NYC Department of Health and Mental Hygiene.
According to health officials in New York City, severe cases of leptospirosis can lead to acute renal and hepatic failure, along with occasional severe pulmonary issues. Symptoms of the infection may include fever, headache, chills, muscle aches, vomiting, diarrhea, cough, conjunctival suffusion, jaundice, and rash.
The incubation period for leptospirosis typically ranges from 5 to 14 days, although it can last anywhere from 2 to 30 days. If left untreated, the infection can result in kidney failure, meningitis, liver damage, and respiratory distress.
Between 2001 and 2023, New York City recorded a total of six deaths attributed to leptospirosis, as reported by the NYC Department of Health and Mental Hygiene.
“In NYC, locally acquired cases typically have a history of a residential or occupational exposure to rat urine or environments (including soil and water) and materials contaminated with rat urine (e.g., handling trash bags or bins containing food waste), health officials said in their press release regarding the uptick in cases of leptospirosis. “Person-to-person transmission is rare. The NYC Health Department conducts inspections and works with property owners to remediate rat conditions, if indicated.”
According to the NYC Department of Health and Mental Hygiene, leptospira bacteria are fragile and can die within minutes in dry heat or freezing temperatures.
“The cold winters of NYC likely limit the extent to which leptospires can survive in the environment,” health officials said. “However excessive rain and unseasonably warm temperatures, factors associated with climate change, may support the persistence of leptospires in more temperate areas like NYC.”
According to the NYC Department of Health and Mental Hygiene, in 2023, half of the locally acquired cases were reported in the warmer and wetter months of June (5) and October (5), which experienced excessive rain and unseasonably warm days compared to previous years.
Instances of leptospirosis must be reported to the NYC Health Department within 24 hours. For further information about the illness, individuals can visit the websites of the New York City Health Department and the CDC.
“As always, we appreciate your collaboration in improving the health of New Yorkers and helping us direct remediation efforts in New York City,” said Celia Quinn, Deputy Commissioner of the Division of Disease Control in New York City.
