Avian Flu Diary: NYC Investigating Another Legionella Outbreak

Legionella Bacteria - Photo Credit CDC PHIL

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Two months ago we were following an outbreak of Legionnaire's Disease (Legionella) in the South Bronx of New York City that sickened at least 133 people, killing 16 (see Updating The South Bronx Legionnaire’s Outbreak). In response, on August 6th New York City Department of Health Commissioner ordered a city-wide order to all owners of buildings with cooling towers to disinfect them within 14 days..

Legionella bacteria thrives in warm water, such as is commonly found in air-conditioning cooling towers, hot tubs, and even ornamental water fountains. When water is sprayed into the air the bacteria can become aerosolized and inhaled.

Those who are susceptible (often smokers, the elderly and the immunocompromised, etc.) can develop serious – even life threatening – pneumonia. The CDC estimates between 8,000 and 18,000 Americans are hospitalized with Legionnaire's Disease each year.

Most cases are sporadic, and the cause is never identified.

Outbreaks, however, spark major public health investigations to isolate, and eliminate the source. Yesterday the New York City Department of Health announced they are investigating another cluster of Legionella in the South Bronx, one that is not connected to the outbreak earlier this summer.

Here is the press release:

Health Department Investigating Cluster of Legionnaires’ Disease in Morris Park Section of the Bronx

The Health Department is currently investigating a cluster of seven Legionnaires' disease cases in the Morris Park section of the Bronx. This cluster is unrelated to the outbreak in the South Bronx this summer that was attributed to Legionella found in the cooling tower of the Opera House Hotel. Patients in the current cluster live or work in Morris Park, range in age from 45 to 75 and are all currently hospitalized. There have been no deaths. New Yorkers with respiratory symptoms, such as fever, cough, chills and difficulty breathing, are advised to promptly seek medical attention.
“We are investigating a cluster of seven cases of Legionnaires’ disease in Morris Park. I urge all New Yorkers to seek care immediately if they have flu -like symptoms, including fever, cough, headache, or difficulty breathing. The Department is taking immediate steps to determine the source and protect the people who live and work in Morris Park,” said Health Commissioner Dr. Mary T. Bassett.
As soon as the possibility of a cluster was identified, DOHMH began an aggressive response:

The Health Department was notified of these seven cases between Sept. 21 and Sept. 27
On Sept. 21, when the first case was reported, the Health Department’s disease detectives began investigating immediately. This work initially involves interviewing patients and reviewing medical records.
Since Saturday, environmental scientists visited all cooling towers and took samples.
Issued a Health Alert to providers advising them to look for symptoms of Legionnaires’ disease, conduct appropriate tests on patients, and provide proper samples to the Department for lab testing
Conducting tests at our Public Health Lab and the New York State Wadsworth Center
Monitoring Emergency Department visits for pneumonia among residents of Morris Park, which have remained at normal levels
Identifying facilities such as nursing homes and senior centers where vulnerable populations live in and near Morris Park. Starting today, the Department will work with other City agencies to send staff to these locations, distributing Frequently Asked Questions about Legionnaires’ disease, answering questions and reminding people to seek care immediately if they have symptoms such as fever, chills and muscle ache.

About Legionnaires’ Disease
Legionnaires' disease is caused by the bacteria Legionella, and New York City sees 200-300 cases each year. Additional symptoms include: headache, fatigue, loss of appetite, confusion and diarrhea. Symptoms usually appear two (2) to 10 days after significant exposure to Legionella bacteria. Most cases of Legionnaires’ disease can be traced to plumbing systems where conditions are favorable for Legionella growth, such as whirlpool spas, hot tubs, humidifiers, hot water tanks, cooling towers, and evaporative condensers of large air-conditioning systems.
Legionnaires' disease cannot be spread from person to person. Groups at high risk for Legionnaire’s disease include people who are middle-aged or older – especially cigarette smokers – people with chronic lung disease or weakened immune systems and people who take medicines that weaken their immune systems (immunosuppressive drugs). Those with symptoms should call their doctor and ask about testing for Legionnaire’s disease. New York City’s drinking water supply and drinking water tanks are unaffected.