EASTERN EQUINE ENCEPHALITIS

Although Eastern equine encephalitis, or EEE, has not been detected in samples taken from around New England this year, officials urge that care be taken to avoid contracting this viral disease, considered to be one of the most deadly mosquito-borne diseases in the United States, according to the U.S. Centers for Disease Control and Prevention’s Web site.

Symptoms in humans tend to take three to 10 days to develop after a bite from an infected mosquito. Many people who contract EEE have no apparent illness. In those who do get sick, symptoms range from mild flu-like illness to inflamation of the brain, coma and death. The mortality rate in those who become ill is about one-third.

People older than 50 and younger than 15 seem to be most susceptible, and also those who work or play in areas where the disease is present, mainly in freshwater hardwood swamps in the Atlantic Coast and Gulf states, and also in the Great Lakes region.

The number of cases is small, mainly because people don’t live close to swampy areas where the mosquitoes live. About 220 cases have been cited in the United States between 1964 and 2004.

There is no human vaccine for the virus, but people can take precautions, such as using an EPA-registered repellent, wearing protective clothing, avoiding outdoor activity when mosquitoes are active – some carriers are aggressive day-biters, according to CDC – and removing standing water where mosquitoes can breed.

Although there is no specific treatment for EEE, medical care can include nursing care, physical therapy and prevention of secondary infections.

About half of those who survive the EEE will have mild to severe neurological damage. – Information from the U.S. Centers of Disease Control and Prevention, www.cdc.gov.

LYME DISEASE

Lyme disease is fairly easy to prevent if you know you have been where ticks live and look for the pest or evidence of its bite. However, for those unaware of the tick bite, Lyme disease is often misdiagnosed, causing longterm illness.

The Centers for Disease Control and Infection (CDC) says Lyme disease is caused by a bacterium carried by blacklegged ticks.

According to their Web site, “Typical symptoms include fever, headache, fatigue, and a characteristic skin rash called erythema migrans. If left untreated, infection can spread to joints, the heart, and the nervous system. Lyme disease is diagnosed based on symptoms, physical findings (e.g., rash), and the possibility of exposure to infected ticks; laboratory testing is helpful in the later stages of disease. Most cases of Lyme disease can be treated successfully with a few weeks of antibiotics.”

The rash typically has a bullseye pattern, and shows up between three and 30 days after the bite. Patients also experience symptoms of fatigue, chills, fever, headache, muscle and joint aches, and swollen lymph nodes. In some cases, these may be the only symptoms of infection, according to the CDC.

Left untreated, Lyme disease can progress to loss of muscle tone, severe headaches and shooting pains, arthritis, joint pain and swelling.

If you’re bitten

Try to avoid areas with ticks, and checking for ticks if you have been outdoors. Discourage deer from coming onto your property, as they carry the ticks that harbor the Lyme bacteria.

The CDC recommends pulling a tick off as soon as it’s found, using tine-tipped tweezers as close to your skin as possible. Pull straight up. Clean the skin with warm soap and water. Don’t use petroleum jelly, a hot match, nail polish or other products.

If the tick has been attached to your skin for less than 24 hours, your chance of getting Lyme disease is very small, but the bitten area should be watched closely.

WEST NILE VIRUS

Pesky mosquito bites are irritating and in some cases, though rare, can cause West Nile virus.

But, the right conditions have to occur for someone to contract the virus.

The West Nile virus is transmitted through the bite of an infected mosquito that has fed on an infected bird. The infected mosquito then bites a human and transmits the infection.

The risk of contracting the infection is low but can be a serious threat to seniors, young children and those with poor immune systems.

West Nile virus can also be spread to people through blood transfusions and organ transplants from infected donors. And, pregnant women or breastfeeding mothers infected with West Nile virus could possibly pass it to their baby.

Symptoms

Illness typically occurs within three to 15 days after someone has been bitten by an infected mosquito.

The majority of people who become ill have no symptoms, though others may experience mild, flu-like symptoms – fever, headache and body aches, often with a skin rash and swollen lymph glands.

In a small percentage of people, more severe infections can cause headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, paralysis and, sometimes, death.

There is no known transmission from birds to people, however, you should not handle birds or any dead animals with your bare hands.

There is no specific treatment for West Nile virus.

Prevention is key

While mosquitoes are active beginning in June, people should be thinking about prevention through Oct. 20.

In warm weather, mosquitoes can breed in any puddle that lasts more than four days. According to the state Department of Health and Human Services, residents can help prevent West Nile virus by following these guidelines:

• Eliminate standing water and other mosquito-breeding locations around your property – Remove old tires that can collect water; dispose of tin cans, plastic and ceramic pots; drill holes in the bottom of recycling containers that are left outside; make sure roof gutters are clean and drain properly; clean and chlorinate swimming pools and hot tubs; aerate garden ponds or stock them with fish; change water in birdbaths at least twice weekly.; and turn over plastic wading pools when not in use.

• Secure your home – Make sure that doors and windows have tight-fitting screens. Repair or replace all screens in your home that have tears or holes.

• Protect yourself from mosquito bites – If outside during evening and dawn hours when mosquitoes are most active and likely to bite, children and adults should wear protective clothing such as long pants, long-sleeved shirts and socks.

Use an effective insect repellent, such as one containing DEET. Repellents that contain Picaridin or oil of lemon eucalyptus have also been determined effective against the virus. Vitamin B, ultrasonic devices, incense and bug zappers have not been proven effective in preventing mosquito bites.

Since West Nile virus was first seen in the U.S. in 1999, in Queens, N.Y., states across New England have been tracking the occurrence of illnesses and the number of reported dead birds tested that could carry the virus.

This year, the West Nile virus has not been identified in New Hampshire, though 2,131 mosquito pools, one horse sample and 56 human samples have been tested so far. In 2007, no specimens tested positive for West Nile virus.

In 2003, three human cases were reported in New Hampshire. Facts about West Nile and other mosquito-borne diseases, the handling of dead birds and information about communities under declared public health threat can be found at www. dhhs.nh.gov or call the toll-free West Nile virus information line at (866) 273-6453.

– Source: New Hampshire Department of Health and Human Services Web site, www.dhhs.nh.gov.