- QUEST FOR BLOOD: Ticks crawl to the top of a blade of grass or leaf edge and smell with their feet to find a meal.
Even the word "tick" is icky. It conjures up disgusting leggy creatures, fat with blood hanging on your dog's ear or tiny, itchy and in intimate areas of your own body.
But what is really icky about ticks are the illnesses they can cause, and if you live in Arkansas, congratulations: There are more tick-borne illnesses here than almost anywhere.
Which is why the University of Arkansas began the Arkansas Tickborne Disease Project, research not confined to ivory towers but reaching out to citizen scientists. The university wants your ticks, and within a couple of weeks you, too, can help its researchers learn more about ticks and the pathogens they carry by going to your local Extension Service office and getting a tick kit. Researchers in the Dowling Lab — named for the UA's Dr. Ashley P.G. Dowling — will take the ticks you turn in, chop them up, and study their DNA.
Krista Garner, who is getting her doctoral degree in what is called medical and veterinary entomology, the study of insects that cause diseases in people and animals, said the project's goals are to collect insects from all over Arkansas to learn where the species concentrate, screen them for the bacteria they carry, and make people — including physicians — more aware that tick bites may be the cause of symptoms they're seeing in their patients.
Arkansas has at least five tick species: American dog ticks, brown dog ticks, Gulf Coast ticks, lone star ticks and black-legged ticks. If you are like this writer, you call those engorged gray ticks you see on Fido "dog ticks" and those little buggers "seed ticks." Garner set us straight.
The big fat gray ticks are females, not necessarily dog ticks, and they are chowing down to feed the "thousands of eggs" they are carrying within them, Garner explained. When they are "replete" — filled with blood — the tick drops off and lays the eggs. "Seed tick" is just a life stage, Garner explained. Ticks feed on blood in all stages, from egg to adult, and they can bite in the larval stage. They look like a tick in this stage, but if you happen to have a microscope on you at the picnic, you'll see the larval tick only has six legs. The other two legs grow in the nymph stage (and now you can see all eight with your naked eye, should you so choose.)
The tick finds its host by crawling to the top of a blade of grass, Garner said, or bush or branch and "questing": By sticking its legs into the air to smell — its legs are like noses — for carbon dioxide and other chemicals that say animals are near. It uses vibrations on the grass to orient itself toward the host and grabs on as the host walks by.
The reason you may not find ticks on you until after they've begun to feast is that their feeding apparatus "is like a two-way straw," Garner said. "One way is bringing blood up and the other way, they're essentially throwing up into you," injecting saliva with anticoagulants and antihistamines, so you don't scratch them off right away. Their mouths, Garner said, are like little saws. But read on anyway.
Not all ticks are infected with pathogens, but when they are, and they stay on your body long enough to transmit them, you can become very ill, even die. Garner said a woman in Oklahoma, untreated for a Rickettsia bacterium, which made her blood vessels leaky, lost her arms and legs.
In 2016, state Department of Health records indicate, two people in Arkansas died of erlichiosis. There were 1,129 confirmed or probable cases of tick-borne diseases, including spotted fever Rickettsiosis (896 cases), erlichiosis (192), tularemia (32 cases) and anaplasmosis (15 cases). Sixty-eight of the state's 75 counties reported diseases; Northwest Arkansas had the highest number of cases and North Arkansas had the highest numbers per 10,000 people.
Southern Missouri, Arkansas and Oklahoma have the highest rates of erlichiosis and spotted fevers in the country, Garner said. Lyme disease, also a tickborne illness, is rare in Arkansas, though two cases have been reported this year.
Since the start of the project, 1,607 ticks have been collected by the lab, provided by citizen scientists and Dowling lab researchers both. Of those, 1,245 were lone star ticks, 272 were American dog ticks, 48 were black-legged ticks (also known as deer ticks), 27 were Gulf Coast ticks and 15 were brown dog ticks.
The species counts and reported cases of illness in Arkansas do not match up, which is another reason why the Dowling lab's investigation into pathogen DNA is important. Though spotted fevers are the most reported diseases, the ticks associated with them — the American dog tick (carrier of Rickettsia rickettsia) and the Gulf Coast tick (Rickettsia parkeri) — are not greatly represented in the lab's collection. Erlichiosis is associated with the lone star tick, the most common tick in Arkansas and also the most "aggressive," Garner said. The lone star also is associated with "Southern tick-associated rash illness," though the cause is not yet known. Anaplasmosis and Lyme disease are transmitted by the black-legged tick. Tularemia, or rabbit fever, can be transmitted by both dog and lone star ticks.
Because ticks lay so many eggs, mutation among the species is quick, Garner said, and there may be bacteria species and subspecies in ticks whose pathogenic nature is unknown.
In the next couple of weeks, 3,000 tick kits will be distributed. They include a baggie, a card on which to record the date and place the ticks were collected, and five preservative-filled vials in which to put the ticks. You can take a vial out on a jaunt and fill it up with as many ticks as you find. Once you've filled five vials, enclose them in the baggie and either take it to the local extension office or mail to the UA. The data is put on a map at comp.uark.edu/~adowling/ARTicks/.
The high number of tick-related illnesses could be related to Arkansas's heat and people's unwillingness to wear long sleeves and pants on a typical summer day, when it's 100 degrees and humidity is 90 percent. To remove a tick that has bitten, Garner said, pinch it close to the skin and pull. Do not squeeze it, so the pathogens within aren't squirted into you. Tick pliers, which come with little magnifying glasses, and tweezers are good tools. Skip the lit-match idea.
Garner, whose fascination with arthropods began when she was only 8 and started raising tarantulas, plans to spend this week catching up on testing all the ticks from last year. The research, which is funded by the Arkansas Biosciences Institute, will be published in a science journal.