Beware the tick.
The tiny arthropods – ticks are not insects, but a type of arachnid, like spiders or scorpions – carry a significant and growing number of diseases. And humans don’t know how to stop them.
Using the right repellent on clothes and skin can keep them away for a time. But on the whole, ticks continue to spread, expanding their ranges and bringing both diseases we know and relatively unknown illnesses with them.
Between 2004 and 2016, rates of diseases spread by vectors like ticks and mosquitoes tripled, with the vast majority of that increase due to the spread of ticks. Experts expect the problem to get worse, as warmer weather allows ticks to spread disease longer throughout the year. Plus, we don’t have a good way to wipe ticks out.
The CDC estimates that there are more than 300,000 cases of the best-known tick-borne pathogen, Lyme disease, every year, which is eight to ten times what’s reported.
Other conditions are on the rise too – and ticks are spreading to new areas.
Maps from the CDC show where each type of tick that plagues the US is most commonly found. Not every disease is spread everywhere a tick can be found. Blacklegged or deer ticks, for example, are found in the Northeast, Southeast, South, and Midwest, but mostly spread Lyme disease in the Northeast and Upper Midwest.
In general, anywhere a tick can be found, the illnesses those ticks can carry could eventually arrive.
Using CDC maps and info, here are the ticks and disease you should look out for, no matter your location in the continental US.
Blacklegged ticks, also known as deer ticks, can spread at least six different illnesses, including Lyme disease, babesiosis, anaplasmosis, Borrelia miyamotoi, ehrlichiosis, and Powassan virus.
These diseases are of varying severity, but are all serious. Lyme disease can cause neurological damage if not treated, babesiosis contaminates the blood bank system (and is like tick-borne malaria), and untreated anaplasmosis can cause kidney failure and even death.
The blacklegged tick in the photo at the top of this story is small, but the nymphs — which can spread these diseases — are even smaller, about the size of a poppyseed.
It can take a tick 24 hours to transmit Lyme disease, so removing these ticks as soon as possible is essential.
For now, Lyme Disease is mostly found in the Northeast and Upper Midwest.
Powassan virus is far more rare, though infections are far more likely to cause neurological damage or death.
This virus can be transmitted within 15 minutes of a bite from an infected tick.
The Western blacklegged tick can also transmit Lyme, but the disease is rare out West, and these ticks tend to feed more on lizards and other small animals.
The brown dog tick can be found around the world.
These ticks are often found – unsurprisingly – on dogs. They can transmit Rocky Mountain spotted fever, which is fairly rare. The all-time high year for cases in the US was 2012, with 4,470 cases reported.
This illness can cause rash, headache, and neurological damage. If it’s not treated, it can become life-threatening.
Adult Rocky Mountain Wood Ticks are most likely to transmit disease to humans.
Along with Rocky Mountain spotted fever, these ticks can cause the flu-like Colorado tick fever and can spread tularemia, a potentially life-threatening bacterial illness.
The CDC describes Lone Star ticks as “very aggressive” biters.
These ticks cause a number of different illnesses, including one little-understood one that’s often referred to as an alpha-gal or red meat allergy.
This is an allergy to a sugar found in red meat and mammal products, including dairy. Bites from the ticks have been spreading the strange allergy, which also seems to increase the risk of heart disease.
Gulf Coast ticks spread another form of spotted fever.
While this illness isn’t as serious as Rocky Mountain spotted fever, it can cause serious symptoms.
The American dog tick, also known as a wood tick, is larger than a blacklegged tick (as seen in the photo at the top of this story).
Like the rest of these ticks, they are most active when the weather is warm.
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