Lyme Disease Cases Rose 21% In Minnesota, Human Anaplasmosis Rate Rose Rapidly

Editor's Choice
Main Category: Infectious Diseases / Bacteria / Viruses
Also Included In: Public Health
Article Date: 08 May 2011 - 10:00 PDT


A record number of people in Minnesota were infected with tick-borne diseases in 2010. With the arrival of the 2011 tick season, authorities are urging people to be especially careful to protect themselves from the black-legged tick.

The black-legged tick, also known as the deer tick, carries the three most common tick-born diseases, and some others. According to MDH (Minnesota Department of Health), the total number of reported cases in 2010 in the state were:

• Babesiosis - 31 cases in 2009. 56 cases in 2010
• Human anaplasmosis - 720 cases (over double the figures of recent years)
• Lyme disease - 1,293. 21% more than the year before.

Dave Neitzel, MDH, a tick-borne disease epidemiologist, said:

"We're seeing a continuing and troubling trend of marked increases in cases of tick-borne diseases in Minnesota. We are particularly concerned about anaplasmosis, with case numbers now rivaling Lyme disease in some areas of the state."

In 2010, the number of confirmed cases of human anaplasmosis surpassed those for Lyme disease in Hubbard, Crow Wing, Cass, Carlton, Beltrami, and Aitkin counties.

Other less common tick borne diseases are also on the rise in Minnesota, authorities inform - many of them can be serious diseases.

Dave Neitzel said:

"We're concerned about new cases of tick-borne diseases that hadn't been detected in Minnesota before 2008."

The black-legged tick also appears to carry a new form of ehrlichiosis, as well as Powassan virus disease - both newer illnesses. Some Minnesotans have also developed Rocky Mountain spotted fever and tularemia, different forms of ehrlichiosis.

Tick-borne diseases can affect humans in a variety of ways - some people experience very mild symptoms or even none at all, while others may develop serious and life-threatening complications. There may be swelling of the brain, organs can begin to fail, and the patient may die.

In Minnesota in 2010 approximately 30% of all patients with anaplasmosis had to be hospitalized - one died. Almost 50% of all cases of babesiosis had to be admitted to hospital, and there was one death.

Minnesota State Epidemiologist, Dr. Ruth Lynfield, said:

"With Minnesota's more common tick-borne diseases reaching epidemic levels in some areas, it is crucial that Minnesotans protect themselves from tick bites to prevent serious tick-borne illness."

The high-season for tick-born diseases in Minnesota is from late spring to the end of summer. Black-legged ticks are also active during autumn.

Protecting yourself from tick bites

People who are in areas where ticks are known to carry disease should:

• Avoid high grass
• Avoid bushy and wooded areas
• Take preventive measures from May to August
• Walk down the center of a path, as far away as you can from overgrown grass, leaf litter and brush
• Ask local authorities where the worst areas are

Protecting your skin

• Use tick repellent on your skin. Repellent with between 20% and 30% DEET is best. Place it on exposed skin and your clothing.
• Permethrin is also an effective tick repellent. It can be found in camping and hunting shops. Apply it once to your socks, pants and shoes.
• Cover as much of your skin as you can with clothing - wear long sleeves, pants rather than shorts, wear long socks.
• There is a greater chance of spotting ticks if your clothes are light colored
• Tuck the bottoms of your pants into your socks
• Tuck your shirt in
• If you are in a particularly tick-infested area, tape your pants and socks so that the insects cannot get inside your clothes

Before you go outside check your clothing and remove all ticks. Wash all your clothes in hot water and dry them in high heat. Even if you are just popping out into your back yard, check for ticks, especially your groin, scalp and armpits. Use a pair of fine-tipped tweezers to remove them.

If you remove a tick that is attached to your skin, your risk of developing a tick-borne disease is very low. Even so, be alert to the potential tick-borne illness signs and symptoms for the next 24 hours.

Checking around your home

Acaricides (type of pesticide) are extremely useful in keeping tick populations to a minimum. The CDC (Centers for Disease Control and Prevention) says that if you apply the pesticide at the end of May or beginning of June, you can bring typical tick populations down by between 60% and 100%. Ask your local authorities to confirm with you when best to apply pesticides. When you apply it, follow the instructions carefully.

Ticks love humid, wooded areas and die quickly in exposed, dry and sunny environments. The following measures can help keep tick populations down:

• Make sure there is no leaf litter, tall grass or brush around your home. Check the edges of your lawn and keep them clear.
• Place wood chips between lawns and wooded areas - this stops them migrating.
• Keep your lawn as well trimmed as you can. Regularly clear leaf litter and brush.
• Make sure that all areas below bird feeders are kept clean.
• Stack wood in dry areas
• Do not place decks, patios and playground equipment near trees and the edge of your yard

Early detection of tick-borne illnesses

The sooner a tick-borne disease is diagnosed and treated the smaller the risks of complications are. If you develop tick-borne disease type symptoms and have been in an area known to have ticks, see a doctor straight away.

The signs and symptoms of tick-borne illnesses may include:

• Exhaustion
• Facial droop
• Fever
• Headache
• Joint ache
• Joint swelling
• Muscle aches
• Rash

Lyme disease has three known phases, click here for more details .

Most tick-borne diseases are caused by bacteria and are treated with antibiotics, except for Powassan disease, which is caused by a virus.

"Tick Transmitted Diseases"
Minnesota Department of Health

Written by Christian Nordqvist
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today

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