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In early July, the Upper East Side saw a cluster of Legionnaires\u2019 cases. Then the Guggenheim<\/a> and the Met<\/a> tested positive for Legionella, which is the bacteria that causes the disease if inhaled. Late last week, it was the Ardsley<\/a>, a prewar, white-glove co-op on the Upper West Side, that became the Legionnaires\u2019 locale of note. All told, as of Tuesday, water in the cooling towers of 76 buildings across the city had tested<\/a> positive for Legionella. According to the city Health Department, 63 people have<\/a> been hospitalized, though 40 have already been discharged. And thankfully, there have been no deaths reported so far.<\/p>\n If this sounds familiar, it\u2019s because the same thing happened around this time last year<\/a>. So how worried should you be about the semi-seasonality of a disease that has<\/a> a 10 percent fatality rate? Is it safe to shower right now? Can you walk past the Ardsley without a hazmat suit? Should everyone on the Upper East Side just decamp to the Hamptons while this gets worked out? We talked to Dr. Wafaa El-Sadr<\/a>, an epidemiologist at Columbia University\u2019s Mailman School of Public Health, about how a reasonable New Yorker can best navigate what\u2019s starting to feel like Legionella season.<\/p>\n Why did this outbreak even happen?\u00a0<\/strong> Can you catch it from someone who\u2019s come into contact with the bacteria?\u00a0<\/strong> And if you have it, how freaked out should you be?\u00a0<\/strong> What happens if you live or work in one of the buildings that have tested positive for Legionella, like the Met?\u00a0<\/strong> So it\u2019s not something that comes in through tap water, for example.\u00a0<\/strong> Are there precautions a person can take?\u00a0<\/strong> Should I avoid walking along Museum Mile?\u00a0<\/strong> How does the city determine the cause of an outbreak?\u00a0<\/strong> The current cluster is on the Upper East Side, but on the west side, the Ardsley\u2019s hot-water system tested positive for Legionella, too. Did the bacteria somehow spread all the way across Central Park?\u00a0\u00a0\u00a0<\/strong> So it\u2019s possible that the people at the Ardsley just checked their own system after seeing cases elsewhere in the city. Which is, I guess, a good thing. As more cases emerge, is it possible that more buildings will be more proactive and forthcoming about their testing?\u00a0<\/strong> Can the city do more to get ahead of this? It feels like a seasonal occurrence now.\u00a0<\/strong> Is climate change somehow to blame here?\u00a0<\/strong> Sign Up for the Curbed Newsletter<\/p>\n A daily mix of stories about cities, city life, and our always evolving neighborhoods and skylines.<\/p>\n Vox Media, LLC Terms and Privacy Notice<\/p>\n
In a place like New York City, Legionella really spreads through the mist or the vapor that\u2019s generated by cooling towers that are often found on the top of large buildings. These cooling towers are a good medium for these bacteria, which look like rods, to multiply and grow. Once you have enough of them, they\u2019re distributed in the vapor and mist that comes out of these cooling towers and then that comes down and settles on the sidewalks or in the air where people are walking.<\/p>\n
It\u2019s spread by actually breathing\u00a0in this mist; it is not passed from person to person.<\/p>\n
Most people who are exposed to this infection do not develop symptoms. Those include\u00a0aches and pains, fever, cough, shortness of breath. But older individuals, smokers, people with chronic conditions like chronic lung disease, chronic kidney disease, heart disease, are particularly vulnerable.<\/p>\n
When testing shows there\u2019s evidence of these organisms in cooling towers, it\u2019s necessary to drain the water, dry them out, then treat them to make sure that you eliminate any evidence of this germ. Then you\u2019re good to go. But it doesn\u2019t mean that you stop monitoring because inevitably it may happen again. That\u2019s why in New York City, there are rules and regulations and guidelines regarding frequent sampling and testing at these cooling towers.<\/p>\n
This organism is not in the plumbing, at least with the Upper East Side cluster. It\u2019s not spread by drinking the water. It\u2019s not spread by taking showers, by using the water to cook, or anything like this. There\u2019s no reason to leave the building or to go elsewhere.<\/p>\n
If you\u2019re going in and out of the building and just being super-careful, you might want to wear a mask, for example, because that\u2019s where the mist would be settling down from the cooling tower.<\/p>\n
For the majority of people, they should not be concerned. If a person does have one of these conditions that make them particularly vulnerable to Legionnaires\u2019, I think it might behoove them to avoid the block, or if they have to walk in that area, maybe they should wear a mask. But it\u2019s only for people who are particularly vulnerable to Legionnaires\u2019 disease.<\/p>\n
There are rapid tests that can be done that can identify that the organism is in the water, which can include both live and dead Legionella. Then there are more sophisticated tests that can be done further to check whether the germ you got from this cooling tower is the same one that you recover from the patient. Those take a longer time to be able to genetically link the source with the cases of Legionnaires\u2019.<\/p>\n
It\u2019s unlikely that it\u2019s an organism from a cooling tower on the East side migrated to the West side.<\/p>\n
When you identify something like this, then people afterward become hyper-vigilant. Maybe they\u2019re looking at their data, they\u2019re testing more regularly, and very importantly, they\u2019re also disclosing it. Maybe a year or two ago, the management of a building may not have felt compelled to let the residents know. But I think now it\u2019s a good sign that there\u2019s more willingness to share public-health issues with the public.<\/p>\n
There is guidance already on the frequency of testing the water. The city should be vigilant in terms of making sure the management companies that manage these buildings are doing this on a regular basis, they\u2019re disclosing this when they have a positive test, and they move ahead and do the mitigation right away. At the same time, I think the city is also doing a good job at disseminating information about Legionnaires\u2019 \u2014 what it is and what it isn\u2019t, how you get it and how you don\u2019t get it.<\/p>\n
I don\u2019t think we\u2019ve proven it definitively, but certainly, as with more hot days and more extreme heat, that change has a huge impact on environmental consequences. And it means we may have heavier, faster growth of organisms like Legionella.<\/p>\n