When Insects Attack!

Hat, long-sleeved shirt tucked in, pants tucked in — that’s probably not your favorite summer attire. Adding insect repellent to the mix makes it worse. But it’s what you have to do these days to avoid the growing number of insect diseases.

Lyme disease is caused by a bacterium, transferred to a human by the bite of a deer tick that has fed on an infected animal. Rodents and deer are the primary hosts. Not all deer ticks are infected, but you have no way of knowing which are or are not.

Juvenile deer ticks are tiny, about the size of a pencil point and a bit larger as adults. They are hard to see, but you should, check for ticks whenever you’ve been where ticks might be. If you see one, remove it with tweezers, as close to the skin as possible. If you have no tweezers, use fingers, protected by tissue or rubber gloves. Be careful not to squash the tick. Clean the site with alcohol or antibacterial wash and wash hands with hot water and soap. If a tick is attached to your skin for less than 24 hours, the chance of getting Lyme disease is extremely small.

Lyme disease starts as a reddish circular rash at or near the site of a tick bite. Other symptoms include chills, fever, headache, fatigue, stiff neck, swollen glands and muscle or joint pain. Symptoms may last for several weeks. If untreated, complications such as meningitis, facial palsy, arthritis and heart abnormalities may occur. If treated with antibiotics at the first sign or symptom, the likelihood of recovery is greatly improved. Contact your health care provider as soon as the rash appears.

“The best solution is to avoid the bite,” says state Public Health Veterinarian Jason Stull, “but we don’t expect people to give up outdoor fun. So take precautions.” That means to cover up and use a repellent that contains at least 30 percent DEET.

Clothing can be treated with Permethrin. Light-colored clothing makes it easier to see ticks. When hiking in a wooded area, stay in the middle of the path. If your yard has a brushy or wooded area, a wood chip strip between brush and lawn will help keep ticks away.

Lyme disease in New Hampshire increased from 271 cases in 2005 to 617 in 2006. Public Health attributes the increase to a greater number of ticks in the state, especially in Stafford, Rockingham and eastern Hillsborough Counties.

Eastern Equine Encephalitis (EEE) is an uncommon, but serious disease caused by a virus. The virus grows in birds that live in freshwater hardwood swamps.

Sometimes the virus escapes its marsh habitat, in mosquitoes that feed on both birds and mammals, including people.

Symptoms of EEE will appear in four to 10 days after the bite of an infected mosquito. Symptoms may include a mild, flu-like illness with headache, fever or sore throat. In very rare cases, EEE will result in infection of the central nervous system, severe headache, stiff neck and a sudden high fever. This can be followed by seizures and coma. About one-third of these patients die from the disease. Many that survive will have permanent brain damage.

As is true with many health threats, children and older adults are more susceptible than others. Those who work or recreate in areas where EEE is prevalent are also at greater risk. There is no treatment for Eastern Equine Encephalitis. EEE is rare; in most years fewer than five cases in the U.S. are reported. There is concern, however. In 2004 there were six positive animals and 19 positive mosquito pools found in New Hampshire. In 2005, there were 54 birds, 16 mammals, 16 mosquito pools and humans that tested positive for EEE. Two people died.

Prevention of EEE involves cities, towns and the state in controlling the mosquito population. The greatest concentration of positive tests has been in the southeast corner of the state.

Personal responsibility is also a factor in prevention. Eliminate standing water in your yard. Change birdbath water often. Use insect repellent with DEET. Wear protective clothing and stay inside from dusk to dark, when mosquitoes are most active.

A recent addition to the plagues of summer is West Nile Virus, another mosquito-borne infection. The virus is transmitted to horses, other animals and in rare cases, people, by the bites of infected adult mosquitoes. Three human cases were reported in 2003.

Most West Nile Virus infections do not cause any symptoms. Mild infections can cause fever and aches, sometimes a rash and swollen lymph glands. In a small percentage of infected people, the disease can be serious, even fatal. Symptoms can include high fever, disorientation, tremors, stiffness and convulsions. Symptoms will appear in three days to two weeks. There is no treatment for the disease. In severe cases, hospitalization is required.

If you are thinking, “I don’t remember these problems when I was a kid,” you are right. Lyme disease was first identified in the U.S. in the 1970s, but did not appear north of Connecticut until 1991. The others are even more recent arrivals. The “why” of their appearance is not clear. It was once thought that deer ticks would not come this far northward. It may be that such changes are part of the larger movement of other animals in response to loss of habitat and changing environmental conditions. Another factor may be that better diagnosis has made the diseases visible.

Whatever the causes, individual actions to reduce exposure to ticks and mosquitoes should be taken. NH