NEWS for North Dakotans
Agriculture Communication, North Dakota State University
7 Morrill Hall, Fargo, ND 58105-5665
May 11, 2000
Tick season arrives just as tulips, daffodils, irises, and blooming trees and shrubs present a chorus of color, and the music of the migrating birds is again in evidence. But an entomologist at North Dakota State University says outdoor enthusiasts should not allow the pleasing sights, sounds and smells of spring to distract them from the message contained in this somber refrain: Ticks transmit disease.
"When you go into areas that harbor ticks, you have to go in with the assumption that they're there at levels of concern," says Phillip Glogoza, extension entomologist at NDSU. "You need to take precautions because the diseases associated with the ticks populating this region are serious and can even be life threatening in some cases."
Ticks are found in wooded areas and open fields where it is brushy. Ticks climb to the top of grasses and on shrubs where they wait for people or animals to pass, Glogoza says. Ticks are most active when it is humid. In shaded areas they may sit and wait on plants all day; in drier areas, ticks are most active early and late in the day. When humidity is low, ticks move down and hide in the soil and leaf litter.
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 diseases associated with the American dog tick include Rocky Mountain spotted fever and Tularemia (rabbit fever), Glogoza says. The blacklegged tick transmits Lyme disease.
Symptoms of Rocky Mountain spotted fever include sudden onset of headache, chills, muscle aches, or a fever which persists more than a day or so, according to the Lyme Disease Foundation Inc., based in Hartford, Conn. A rash may occur about the fourth day of illness, and delirium, shock or even kidney failure may occur if not treated. Tularemia symptoms include repeated spikes of severe fever, swollen lymph nodes that develop into skin ulcers, inflammation of the conjunctiva (the mucous membrane that lines the inner surface of the eyelids) and pneumonia. Lyme disease may initially present itself as a red skin lesion at the site where the tick bite occurred. The size of this injury can expand to become a bright red ring with a clear center that feels hot to the touch. 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.
According to epidemiologist Kirby Kruger with the North Dakota Department of Health, there were two recorded cases of Rocky Mountain spotted fever in the state in 1998 but none in 1999. There was one reported case of Tularemia (rabbit fever) in 1999. There were no reported cases of Lyme disease originating from sources within the state during either 1998 or 1999.
"Minnesota is one of the states where Lyme disease is a concern," Glogoza says.
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.
"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.
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, outdoor infestations are likely to occur in those areas where pets spend a great deal of time, such as shady sites.
"It doesn't happen as much inside, but it can," Glogoza continues. "I've seen cases where people have ticks in their home because their pet has become infested."
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.
###
Source: Phillip Glogoza (701) 231-7581
Editor: Dean Hulse (701) 231-6136
Click here for a pdf version of this graphic. (13KB b&w illustration)