NEWS for North Dakotans
Agriculture Communication, North Dakota State University
7 Morrill Hall, Fargo, ND 58105-5665

May 13, 1999

It's Time To Defeat Ticks

It's tick season, a time for enjoying the great outdoors and foiling the instinctive plans of those bloodsucking arachnids, which can pester, infest and in some cases, spread disease in humans, pets and other animals. The keys to battling these bugs successfully center on identification and prevention, says a specialist at North Dakota State University.

"Wood tick is the common name most people apply to the four or five species present in this region," says Phillip Glogoza, extension entomologist at NDSU. "It encompasses about everything people encounter, except when they start talking about the deer tick."

The most prevalent tick in North Dakota is the American dog tick, whose adult body is light brown with grayish-white speckles on its back and near its head. In contrast, the adult blacklegged tick (deer tick) is about half the size of the American dog tick and looks completely black to the naked eye, but under magnification it appears orange-brown, explains Glogoza. All tick species are capable of transmitting disease, but the diseases most often associated with the American dog tick and the blacklegged tick, respectively, are Rocky Mountain spotted fever and Lyme disease.

According to a disease report published by the North Dakota Department of Health, there were only three recorded cases of Rocky Mountain spotted fever in the state from 1984 through 1996. From 1993 through 1996, there were only four cases of Lyme disease reported.

"Tick-transmitted disease is not something that we see very often in North Dakota," Glogoza says. "However, Minnesota is one of the states where Lyme disease is a concern."

Lyme disease may initially present itself as a red skin lesion at the site where the tick bite occurred, Glogoza says. The size of this injury can expand to become a bright red ring with a clear center that feels hot to the touch. This ring may develop within four to 20 days after the tick bite occurs. Other symptoms include fatigue, chills, fever, headache, sore throat, muscle pain, and nausea or vomiting. People who suspect they may have contracted Lyme disease should contact a physician immediately.

Ticks spread disease while on their quest to obtain warm-blooded meals. The life cycle of ticks extends for two years or longer, depending upon the species. Adult female ticks feed on hosts in order to produce their eggs, which they lay in late spring to mid-summer, Glogoza explains. The resulting larvae do not feed on warm-blooded hosts until the following spring, when they feed, molt, develop into nymphs, feed again and then become adults, thereby completing the cycle.

"Tick larvae and nymphs are more likely to feed on small mammals such as mice or squirrels. The nymphs of blacklegged ticks are extremely difficult to detect because they are about the size of a fleck of pepper," Glogoza says.

Regardless of life-cycle stage, tick behavior is similar among species. The insects populate areas where warm-blooded hosts are likely to frequent. Glogoza says ticks climb vegetation and from this perch simply wait for a host to pass by so they can cling on in hopes of snatching a blood meal.

Keeping grass and other vegetation short around the home is a good tick-prevention strategy, Glogoza says. In landscape shrubbery and other areas of the yard where close-cutting isn't possible, using an insecticide can limit tick populations. In households with pets, infestations are likely to occur in those areas where pets spend a great deal of time, such as shady sites.

"I've seen cases where people have ticks in their home because their pet has become infested," Glogoza says.

In grassy or wooded areas, a combination of protective clothing and repellent works best for people, Glogoza says. Long-sleeved shirts and long pants with cuffs tucked inside of socks prohibit tick access to skin. Repellents containing DEET are applicable to either clothing or skin, but repellents containing permethrin should be restricted to clothing only.

Besides checking their pets for ticks, owners can select from a number of products, ranging from dips to sprays to powders—even vaccines that protect dogs against Lyme disease. Glogoza recommends consulting a veterinarian to help determine which products might be best suited to individual situations.

"The typical North Dakota resident probably doesn't have to worry about Lyme disease," Glogoza says.

However, residents of states where blacklegged ticks have been documented and nonresidents who frequent these tick-infested regions should talk with physician about the pros and cons of the human Lyme disease vaccine. In Minnesota, Glogoza says the area generating the most tick concerns is the southern portion of the lakes region.

"Typically, you don't feel a bite from a tick, so it's a good idea to check yourself after returning from trips to known tick-infested areas. Wearing light-colored clothes makes this easier. Save any specimens you suspect might be blacklegged ticks for identification later," Glogoza concludes.

The correct way to remove a feeding tick is to use tweezers or tissue paper and grasp it as close as possible to the skin of the host before gently pulling straight out. Glogoza says it's important not to squeeze a tick's abdomen during removal because this may cause the insect to inject fluid into the host, an action that could bring about infection. Wash the bite area and apply an antiseptic such as rubbing alcohol or iodine.

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Source: Phil Glogoza (701) 231-7581

Editor: Dean Hulse (701) 231-6136