Avoid bug-borne diseases this summer

Dr. Bobbi Pritt.

Planning to hike over the summer? Don’t forget the Deet — and maybe pack tweezers, while you’re at it.

There are plenty of diseases that can be transmitted by bugs such as ticks and mosquitos. We talked to Dr. Bobbi Pritt, a Mayo Clinic pathologist, about Lyme disease and West Nile virus — two prevalent vector-borne diseases in the U.S. Read on to learn why Minnesota Lyme disease is the worst, and how to follow the "ABCs of bite prevention."

So lyme disease is a big concern this time of year.

That’s the number-one vector-borne disease in all of North America. Out of all the things transmitted by bugs, mosquitoes and ticks, Lyme disease is the biggest.

What are some of the symptoms of Lyme disease (Borrelia Burdorferi)?


At the site of a tick bite, you often get a little red mark. That doesn’t necessarily mean you’re infected, but if that red mark gets bigger and bigger — it often looks like a target — that is the classic symptom that people will see. But it’s not always seen. … If you see that, it’s worrisome and you want to go to your doctor right away. Other symptoms that a person with Lyme disease may have would be a fever, joint pain, body aches, or just … feeling not well in general. Any of those, in the summer, you want to check for a tick-borne disease.

You found a new form of Lyme disease in Minnesota, didn’t you?

Yeah, we named it Borrelia mayonii after the Mayo Clinic. … That actually has some unusual symptoms. The rash is spread out, it doesn’t usually have that nice bulls-eye, and you can actually have multiple spots all over your body. Our patients with Borrelia mayonii were pretty sick, too. Not just fever, but really, really profound fatigue, to where they could hardly stay awake. Some had double vision, and some were even hospitalized for short periods of time. … That’s something that we need to watch out for in this area of the country.

Let’s say there’s a tick on you post-woods trip. What should you do?

Taking a shower can help, you just strip off and do a thorough tick check that way. The CDC recommends that, it probably makes it a little bit easier to find ticks. You want to be sure to check areas that might be hard to see, like your scalp and your back. … If you see a tick on you, and it’s stuck in your skin — what we call "embeded" — you want to get it off as soon as possible. … The best way is to take fine-tip tweezers, grasp the tick as close to the skin as possible, and pull it out smoothly. Don’t twist it, don’t squish it. … If you damage the tick, you … might force some of the organisms inside it into your system, so you might increase the risk that you’re going to get infected. The other thing is, is in our area, because we have some areas with a high level of Lyme disease, you may want to save the tick to bring to your doctor — especially if it’s really, really swollen. If it’s been attached for 36 hours or more, it’s going to be really engorged with your blood, and that’s a risk factor for Lyme disease, because the tick has to feed on you for 36 hours or more to transmit the bacterium for Lyme disease. If it’s really swollen, the recommendations are to take the tick, put it in a plastic bag, and then bring it to your doctor and tell the doctor that it was on you … they will probably prescribe an antibiotic to prevent Lyme disease.

What should you do if it looks like a recent bite?

If you’re in an endemic region and you get bit all the time, you can just throw the tick away — flush it down the toilet, that’s probably the safest way to get rid of it. What I tell folks to avoid is those folklore remedies to get the tick off.

There are things you can do that will probably get the tick off, like you can put petroleum jelly on it, or burn it with a matchstick, or put nail polish on it. But those aren’t really recommended, because it could hurt the tick, again, and increase your chances of getting infected. And it’s going to take longer. … Some of the viruses that ticks can also transmit can be transmitted as quickly as in 15 minutes. If you find a tick on you and it’s embedded, you don’t want to wait to drive home. … Just try to pull it off right away."


Let’s move on to mosquitoes. How concerned should hikers be about West Nile virus?

West Nile virus is found throughout the states. … Most people either don’t even know they’re infected, or get a very mild disease. About 10 percent of people do get a more severe disease, and it actually can be so severe that you can die from it. It can attack your brain and cause a lot of damage — even partial paralysis. … That’s seen in less than one percent of people who get the infection."

What are the more mild symptoms of West Nile?

"It would be like what we think of as a flu-like illness. Fever, tiredness, headaches, body pains. Honestly, it’s a lot like a tick-borne disease, and so we kind of think of them together. You can get a transient rash on your body, and then that will just go away on its own."

Pritt’s Tips for Preventing Bites:

Follow the ABC's of

A - Avoid the areas where ticks will be.If you’re hiking, stay in the middle of the trail and avoid walking in tall grass, where ticks (and other bugs) will lurk. Mosquitos tend to be out at dawn and dusk, so try not to be out at those times.


B - Bug spray on exposed skin.Deet will repel most of the critters you’ll encounter in the woods. Check the EPA website for a list of repellents that will protect from ticks and mosquitoes. Check the active ingredients and make sure you know how long your product will last. Mosquitoes are easier to repell than ticks — if you pick a product that repells the latter, you’re also going to be safe from mosquitos. And consider applying drops to your pets to kill any bugs that bite them.

C - Cover up with clothing.Putting a fabric layer in between you and bugs (long pants tucked into socks, or even long sleeves), will go a long way toward preventing tick bites. Mosquitoes may bite through them, though. Check yourself for lingering bugs when you’re done hiking, though.

Ticks are arachnids, like spiders. They have eight legs. But unlike your friendly neighborhood crawlers, they don’t feed on insects — just blood.

Dr. Bobbi Pritt examining a woodtick parasite.

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