There’s an oft quoted (and dubious) statistic that, in New York City, you are never more than six feet away from a rat. New York City even has a Rat Information Portal to track rat activity (seriously). Whether the six-foot adage is true or not, there are certainly a lot of rats in New York City. And they bring with them a lot of diseases.
Current health risks associated with Norway rats in general — that is, the brown rat you see everywhere — include hepatitis E (as recently examined in Vietnam, Indonesia, and China), the hantavirus (and you can read about how it affected one pregnant woman in France here), and leptospirosis, the rates of which varied considerably in one neighborhood in Vancouver.
The city of New York has considered building a database of rat viruses, but experts say that just knowing what the rats are carrying won’t have a huge impact on public health. For a while after Hurricane Sandy, there was some nervous talk of rats who were displaced from their homes would coming up from above ground into new areas, bringing with them disease. But so far there has been no increase in rats above ground.
While there’s nothing to be done to get rid of rats entirely, New York City is certainly trying to figure out how to push them out. But perhaps we should update the old phrase, with something like: “You’re never more than six feet away from a rat, and its plague, hepatitis, hantavirus or leptospirosis.” Doesn’t roll of the tongue quite as well though.
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