“Two scientific surveys of New York City's seamy side have turned up enough evidence of past and present pests to kick a hypochondriac into high gear”, reported an NBC News article a few weeks ago. This description offers an interesting glance at the media hype that sparked earlier this month from two recent studies that looked at 1) NYC rats, their external parasites (lice, mites, fleas), and associated diseases, and 2) germs of the City’s subway system.
We saw headlines like "Grossest. Thing. Ever: New York City Rats Covered in Black Death Fleas" (Yahoo Health), "Terrifying Microbe Map of New York's Subway System Reveals Superbugs, Anthrax and Bubonic Plague" (Daily Mail), and “Your Subway Seat Mate — Bubonic Plague” (Yahoo Health) alarming the public about the studies’ findings.
Now, a couple questions that come to mind: Was this hype really justified? And if so, what does it all mean for us? Let’s review…
It’s true, the rat study —by a Cornell and Columbia University research team— did find over 6,500 fleas, lice and mites (from 133 rats sampled), including 500+ Oriental rat fleas — infamous for their role in transmitting the bubonic plague, also known as the Black Death. This of course poses a scary threat, since the disease wiped out more than half of Europe’s population in the 14th century. And — unlike some might think — it is still found in different places around the world, including the U.S. Southwest (roughly a dozen cases each year).
However — none of the fleas collected carried the plague (you can sigh with relief!). They did carry other nasty diseases, though, like various strains of Bartonella bacteria, which can cause a wide range of clinical conditions. And remember, we’re not even talking here about the pathogens and diseases that rats themselves carry — some of which can have serious consequences for us.
Even though an outbreak of the plague seems highly unlikely — thanks mostly to modern medicine —, the researchers still expressed some concern. Based on the study results, "If these rats carry fleas that could transmit the plague to people, then the pathogen itself is the only piece missing from the transmission cycle" explained study author Matthew Frye, a NYS IPM’s urban entomologist at Cornell University.
To make things more confusing — the second study I mentioned, a scientific sampling of bacteria and other microbes found in NYC subways, found traces of partial DNA matching the bubonic plague, along with other pathogens (now you’re probably thinking aha!, or oh no!). However, the research team —from Weill Cornell Medical College— found no evidence that the samples were alive. Not only that, but most of what they found was non-harmful bacteria, commonly found in the human body. Their message to the public: There’s no reason to be alarmed (in terms of these findings, of course) — though “it is a gentle reminder to wash your hands”.
SO, all in all, more than sending us home to panic and lock our doors, I see the message of these studies as one of caution. And a reminder of how critical it is to work together to manage pests and keep their populations under control — and that means everyone! That’s not only a key principle of integrated pest management (IPM), it’s also one of the reasons it is more effective and successful than the traditional rodenticide approach.
Think of it like this: in a crowded city like NY, what are the chances for the pest control folks (municipal and even private) to ‘beat down’ the rats if people don’t dispose properly of their trash, keep their home and surroundings clean, and report rodent problems to their landlords right away?
The researchers’ advice — as well as ours: Prevention (making sure pests can’t get access to shelter, food or water, for instance sealing gaps and installing snug-fitting door sweeps, or fixing a leaky pipe) and sanitation (removing and cleaning every possible food and water source — indoors and out — be it dirty dishes, spilled soda, or an open garbage can).
Now, don’t forget, rats and mice have evolved with us throughout history, so they are as adapted to our environment — urban and rural — and way of living as we are. They are intelligent creatures, with complex behaviors and capabilities, a cautious nature, and highly adaptable (as more and more studies show) — that’s why they’re everywhere! So chances are we won’t get rid of them anytime soon (not fully at least). BUT we can, and this recent hype illustrates why we should, focus our efforts to keep these pests at a tolerable level — both for our quality of life and our health.