The number of ticks are increasing — and so are the diseases they carry

Roger McKinney
Columbia Daily Tribune
Ram Raghavan, professor at the University of Missouri College of Veterinary Medicine and School of Health Professions, examines ticks he has collected on a research trip. Raghavan has collected hundreds of ticks as cases of tick-borne diseases are increasing in the region with his research published in a recent study.

With warmer weather and more activities outdoors and in nature, there's an ever-present danger around that experts say is becoming more plentiful.

Ticks can cause at least 15 illnesses, according to the Centers for Disease Control and Prevention. There were 50,865 documented cases of tick-borne diseases in the United States in 2019, an increase from 22,527 cases in 2004.

Ticks are parasites — large mites that drink the blood of animals and humans.

Ram Raghavan, professor in the University of Missouri College of Veterinary Medicine and School of Health Professions, spent parts of prime tick season from 2014-2017 with former graduate student Ali Hroobi near Pittsburg, Kansas, collecting and identifying 15,946 ticks. His findings have been published in a new study.

The area was chosen because it is near the borders of Missouri, Kansas, Oklahoma and Arkansas — and there are a lot of ticks there, Raghavan said.

The study identified four species, the most common being the lone star tick and the American dog tick.

Lone Star Tick (Amblyomma americanum).

"They all transmit a number of diseases," Raghavan said.

There are some new tick-borne viruses — the heartland virus and the Bourbon virus. The Bourbon virus was named for Bourbon County, Kansas, north of Pittsburg, where it was first identified.

"These viruses have killed," Raghavan said.

The number of tick-borne diseases is increasing, which Raghavan attributes to several factors.

One is poverty, though he said that is hard to prove. The area where he collected the ticks has a greater number of tick-borne diseases and has a higher poverty rate than Boone County, for example.

It could be related to the increased amount of work and activities outside and in nature that lower-income people may experience, he said.

Climate change is another factor, he said. It was evident just during the period he and Hroobi collected ticks, he said. Previously, one didn't see many ticks until May.

"Now, ticks are showing up in late March," he said. "We also see ticks very late into the season. Now we are actively collecting ticks into September and October."

This map shows the distribution of Lone Star ticks in the United States.

Missouri's mail-in tick project

In a separate effort, the Missouri Department of Conservation is partnering with A.T. Still University in Kirksville to document tick species throughout the state. It's enlisting the help of the public to collect ticks, asking residents to mail ticks to the university for the study.

The state agency provides instructions for mailing the ticks on its website, as does the university.

"There's no verified database, that's step one," said Matt Combes, the Conservation Department's ecological health unit science supervisor, of one goal of the study.

"We also want to test for pathogens they carry that can cause human diseases," Combes said of the other goals.

There's also information on the A.T. Still University website. It shows that as of Thursday, 395 ticks had been mailed in from Boone County so far, including deer ticks, dog ticks and lone star ticks.

The collection is scheduled to last two years, with information to be shared with the Missouri Department of Health and Human Services and the CDC, Combes said.

How to avoid ticks and all that comes with them

Combes and Raghavan shared their advice on how to avoid ticks.

"The best thing is to avoid places where the ticks are," Raghavan said.

Wear protective clothing, including long pants and long-sleeve shirts when in nature, they said. Spray repellant that contains DEET on your clothes. Stay on marked trails. Keep dogs on their leashes.

Examine yourself carefully after being in areas where ticks live. Wearing light-colored clothing makes it easier to spot ticks, Combes said.

"Jump in the shower" after an outing, Raghavan said.

"It seems like quite a chore, but it's necessary to avoid a nasty disease," Raghavan said.

If a tick does attach to your skin, it must be removed very carefully with tweezers, Raghavan said.

Seek medical attention if you come down with a fever after a tick bite, Raghavan said.

rmckinney@columbiatribune.com

573-815-1719