Lyme disease a growing concern

This article submitted by Aaron Ziemer on 7/7/99.

Lyme disease is becoming a growing concern among many Minnesotans.

Lyme disease is carried by the black-legged tick (deer tick). The disease can not be carried by the common wood tick. There have been five verified cases of lyme disease reported in this part of Minnesota in the past year. The numbers seem fairly low, but Minnesota is still indicated as one of the endemic areas.

There is a definite and easily identifiable rash that goes with lyme disease. The rash is shaped like a bull's-eye. It is a large circular rash with a dot in the middle. The name of the rash is Erythema Migrans or E.M. Seventy-five percent of people will get this rash if they have been infected by a black-legged tick.

"We are becoming more aware of the problem," said Dr. Randy Zimmerman of Paynesville Area Health Care System.

Who's at risk and high risk areas
Although this area is not one of the higher risk areas of the state, Minnesota, Wisconsin, and New England are the three highest endemic areas in the United States.

"A lot of hunters and anglers who get ticks are at risk," added Zimmerman. "If you get lyme disease you are not exempt from getting it again."

According to Zimmerman, Minnesota is considered an endemic area, but is not as bad as Wisconsin or parts of New England.

"St. Croix river area and parts of Connecticut are two of the highest areas for lyme disease," said Zimmerman.

Ticks like the moisture of a hot and humid day so on those days there are more ticks out there than on cool dry days.

There is also a higher likelihood of finding ticks in higher vegetation than there is in grass that is cut short.

Black-legged tick life cycle
Since only about one percent of the black-legged tick population is born infected with Lyme disease they usually pick it up along the course of their life cycle.

Black-legged ticks have four stages. They are egg, larva, nymph, and adult. The ticks on average have a two-year life cycle.

As a larva the ticks must find a source of food. The usual first victim is the white-footed mouse. This small animal is a carrier of Lyme disease. Up to about 70 percent of the white-footed mouse carry the Lyme disease bacteria. As the ticks injest the blood, they usually also become infected with the Lyme disease bacteria.

After their meal the black-legged tick will usually go back into the leaf litter and wait to become a nymph before venturing out to find another victim.

During the nymphal stage the highest incidence of lyme disease is reported. These cases are reported during the months of May through August, although reports can come in for many months into the fall.

Once again the black-legged ticks feed usually on the white-footed mouse, but can also feed on humans, dogs, and deer.

After that meal the tick usually will go back into the leaf litter once more until it becomes an adult tick.

"The adult black-legged tick usually feeds on deer, dogs, or humans," said Zimmerman.

Adult ticks are easily noticeable by human eyes, but, we should still check for ticks closely and carefully.

Infection and treatment
In order to be infected with Lyme disease the black-legged tick must feed on a person for at least 48 hours. The reason for this is because it is going to take some time for the tick to pass the bacteria through saliva or back through the blood.

There are a couple of warning signs that indicate someone may have been infected with Lyme disease.

The Erythema Migrans rash is probably the most identifiable, according to Zimmerman.

The other noticeable one is flu like symptoms, including headache, stiffness, and nausea.

After a while it can lead to arthritis, headaches, Bells Paulsey. stiffness, especially in neck area, swollen joints, and a slow heart rate, due to an electrical block.

Lyme disease is easy to treat though. Moxicylin is one of the antibiotics that can treat it, and for more advanced cases some intravenous antibiotics need to be used.

"The blood test doesn't show up for at least a week, but if the rash is there we would begin treating," said Zimmerman.

There is also a new vaccine to help prevent Lyme disease. It is called Lyme-X.

The vaccine is given in three parts. The doses are given right away, the second shot is given a month later, and the final one is given a year later.

"We treat ages 15-70 with the vaccine," said Zimmerman. "There is also a study going on to lower the age from 15 to four."

Zimmerman added that he was a believer in the vaccine and had already begun getting the vaccine for himself.

There are other measures that could be taken as well to avoid the ticks. Keeping yard grass short, wearing long pants and long sleeved shirts when going into long grass, applying a bug spray with DEET, tucking pant bottoms into socks to stop ticks from being able to crawl under, and staying inside on hot and humid days.

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