Ticks Are Thriving—And Spreading Illness—More Than Ever. Here’s What to Know

These little bloodsuckers are having the time of their lives right now, so protecting yourself from the diseases they carry is key.
a tick on a blade of grass
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Last spring I took my dog on a walk in a state park while visiting family in Florida. It was a cool day (for Florida, anyway), and the trail was lined with tropical plants. Just as I was feeling stoked that I found a beautiful new hiking spot, I noticed a black spot on my dog. It was a tick. 

Gross, but no big deal, I thought. I pulled it off and continued onward. Within a few minutes, I noticed another tick—then another, and another, and another—on him, but also on my arms, shoes, and socks. By the end of the walk, I had pulled a total of 16 ticks off of my dog and myself (16!!!!). I grew up near the woods in Pennsylvania, so I’m no stranger to the occasional tick bite, but this was absurd. 

I wondered: What the heck is going on with all these ticks? As it turns out, these little bloodsuckers are having a heyday. There are more reports of tick-borne illnesses (like Lyme disease and babesiosis) than ever before in the US, and the warming climate is one big factor that’s making ticks more active, resilient, and unpredictable. If you have plans to camp, hike, or even just spend time outdoors this summer, here’s what to know about why ticks are thriving in grassy, wooded places more than ever, and how to take steps to protect yourself from getting sick from their bites.

Why are there so many ticks right now?

Tick-borne diseases are significantly underreported, but, even so, experts have seen a 25% increase in documented infections between 2011 and 2019, which is the most recent available data from the CDCJanet Foley, PhD, DVM, a veterinarian and disease ecologist at the UC Davis School of Veterinary Medicine, tells SELF that there are a few things going on. That uptick is happening because, one, people are more aware of ticks and the dangers they pose, and two, compared to even a decade ago, we have better surveillance systems in place to catch cases when they happen.

But that upward trend isn’t only due to an increase in detection: Climate change is also causing big shifts in ticks’ actual behavior that contributes to their spreading illnesses. Ticks are highly sensitive to their environment, so any fluctuations in temperature, humidity, and rainfall, among other factors that affect their habitats, hugely impact them, says Dr. Foley. Ticks that prefer cooler, wetter areas—like black-legged ticks (a.k.a. deer ticks), which can transmit Lyme disease, babesiosis, and Powassan virus—have been pushed north to new locations (hello, Canada). Those that do best in dry, hot conditions—such as the dog tick, which can carry Rocky Mountain Spotted Fever—are flourishing, particularly in the Southwest: According to Dr. Foley, cases of Rocky Mountain Spotted Fever have significantly risen in recent years, most likely due to the warmer weather. 

The result: We don’t really know where ticks, and the diseases they spread, are headed. “Across the board, one of the most severe problems is that we start to not know where to expect disease, and that means that the local doctors and local people at risk don’t really know what to do to protect themselves,”  says Dr. Foley. 

Adding fuel to the fire: Much of the country just had a super mild winter—and mild winters tend to mean more ticks. Take California, for example, where ticks are out in full force this year. “We have more ticks than I’ve seen in so many years,” says Dr. Foley. The reason, she says, is that tick activity usually picks up in October. Then it quiets down in January and springs back into action in March. But California’s winter was so mild—and wet, which these little arachnids love—that the ticks never took their wintertime hiatus. Instead, they hung around—living, feeding, reproducing. “They didn’t need to go in this quiet stage, and now there’s tons of them,” says Dr. Foley. And since the majority of the US similarly experienced a warmer-than-usual cold season last year, an increase in ticks is likely to bear out more broadly, per a report from the Associated Press.

What are some of the most common tick-borne diseases to be aware of?

There are 18 recognized tick-borne diseases in the US so far, and at least 27 globally. Some of the most common ones in the US, and the ones you’ve maybe heard of, are Lyme disease, anaplasmosis, babesiosis, and Rocky Mountain Spotted Fever. Different ticks can carry different pathogens in different areas. (You can see what’s crawling around near you on this map from the CDC).

They’re all characterized by some variation of what Dr. Foley calls a flu-like illness, which leads to symptoms like muscle pain, fever, fatigue, and headache. This means it can be tough to know what’s making you feel sick (especially if you never saw a teeny tick on your body). With Lyme, for example, most people infected with the bacteria will feel better with quick treatment and time, but a small percentage of these folks may not respond to antibiotics, and are left with lingering and potentially disabling symptoms and complications. “In the worst-case scenario, it can change people’s lives,” says Dr. Foley. Even worse than that worst-case scenario: Very rarely, some diseases, like anaplasmosis, can be fatal. 

One big thing to keep in mind: Getting bitten by a tick doesn’t automatically mean you’re going to get sick. A report from 2018 found that up to 11% of nymph (a.k.a. young) black-legged ticks are infected with the bacteria that causes Lyme in the Northeast, whereas fewer than 2% of these nymphs carry that bacteria in the West.

And disease transmission usually doesn’t happen immediately after a tick bite. According to Dr. Foley, how quickly a disease is passed on after a tick bite depends on the pathogen it’s carrying, but, as an example, it can take about two days for a tick clinging to and feeding on its host (hopefully not you) to transmit Lyme. (One exception: Compared to most other tick-borne diseases, it can take just 15 minutes for an infected tick to pass on the Powassan virus, which is much rarer.) 

How to protect yourself from ticks this summer

So, what’s this all mean for you as the weather continues to warm up? Given that these pests are going to be everywhere, including in areas they don’t typically reside, you may want to be extra vigilant. 

The most effective way to avoid tick-borne diseases is to avoid getting bit by a tick. When you go out for a walk or hike in grassy or wooded areas, dress with skin protection in mind, says Dr. Foley. Think shoes that completely cover your feet, long pants tucked into socks (since these little vampires tend to hop on you from below, then crawl upward), and—less important but still worth it, in temperatures that allow for it—a long-sleeved shirt (light colors will help you spot the bug more easily). You can also apply a product that contains at least 0.5% permethrin, a highly effective insecticide, on your clothes and gear (but don’t put it on your skin!). Some insect repellants, like products that pack roughly 20% DEET or picaridin, can repel ticks too, but they aren’t foolproof.

When you’re headed inside, take off your shoes and change into fresh clothes at the door to avoid bringing ticks into your home, Dr. Foley suggests. (As someone who’s found ticks in their bed on more than one occasion, I can assure you this step is worth it.) Do a full-body tick check, and take a good look at the clothes and shoes you had on too. If you were in a particularly tick-filled area (so, those wooded, brushy, grassy locations), take a shower. Rinsing off right after spending time outdoors can help dislodge ticks from your body and make you more aware of any areas you may have missed as you scan under your arms, inside your belly button, behind your knees, and other nooks and crannies, says Dr. Foley.

If you spot a tick on your body, get it off as soon as possible. (Here’s SELF’s guide to safely removing ticks.) “The chances of you developing disease are much worse if it stays on you longer,” says Dr. Foley. 

It’s normal to notice irritation after a tick bite, so expect to see or feel some signs of that, like itching, minor swelling, and redness or other discoloration (depending on your skin tone). What you don’t want to see is that circular “bull’s-eye” rash (see what we’re talking about here), which is a telltale sign of Lyme disease in a majority of cases. If you develop that symptom or a fever or headache within a day or two of the bite, contact a doctor as soon as you can. They should run some tests, and if need be, prescribe treatment (which varies depending on what you may have, but often includes antibiotics). The faster you can get those meds, the better off you’ll be. 

Dogs and cats can contract tick-borne illnesses, too, so make sure they’re up-to-date on their tick protection meds, says Dr. Foley. While they can’t spread these diseases to humans, they can bring infected ticks into your home (again, I’ve been there), so look them over from head to toe anytime they’ve been outside too.  

Even though ticks skeeve me out, I haven’t given up my hikes—though I’ll admit that day in Florida was a major wake-up call that I need to do a better job of checking myself and my pup after our walks. So far this year, I’ve already pulled two of these bloodsuckers off of my dog, one off myself, and a fourth from a blanket (and it’s only June!). At least I’m catching them before they hang on and become a real problem—even though it makes me squirm, it’s so worth it.