West Nile Threat Elevated to 'Moderate' in Needham

State officials are advising Needham residents to take extra precautions against mosquito bites now that the Massachusetts Department of Public Health has increased the West Nile virus threat level to "moderate" in Needham, Wellesley, Waltham and Weston.

The urge for increased vigilance follows discovery of a fourth case of the West Nile virus in a human in Massachusetts, according to a press release sent out by the office of State Senator Richard Ross on Thursday, Aug. 30.

The fourth case is a Newton woman in her 50s who was briefly hospitalized and is now recovering, according to a release sent out Thursday by the Needham Health Department.

Health officials are waiting to confirm six more probable human cases of West Nile virus in Middlesex County, Hampden County and Essex County, according to the press release.

“The threat of mosquito-borne illnesses continues to rise throughout the Commonwealth,” Ross said in the press release. “It is imperative that we take all necessary precautions to prevent mosquito bites and protect ourselves and our loved ones from these dangerous diseases.”

So far in 2012, mosquitoes infected by the West Nile virus have been found in 93 communities in the Commonwealth, according to the press release. Two cases of humans infected by the virus have been found in Middlesex County, while one case was found in Berkshire County.

"Health officials are predicting that Massachusetts is on track to have the highest number of WNV-positive mosquito pools since 2000, when WNV was first seen in the state," according to the press release.

While the West Nile virus can infect people of all ages, those over the age of 50 have a higher risk of severe complications from the virus, according to Senator Ross' office. Most people infected with the virus don't experience symptoms, but those who do may experience fever and flu-like illness. Occasionally, a more severe illness can occur, although it is rare.

State officials recommend residents take the following steps to protect against mosquito-borne illnesses:

• Always apply insect repellent when outdoors. Look for a repellent with DEET (N, N-diethyl-m-toluamide), permethrin, picaridin (KBR 3023), oil of lemon eucalyptus [p-methane 3, 8-diol (PMD)] or IR3535, and follow all instructions on the product label. Please note that DEET products should not be used on infants under two months of age and should be used in concentrations of 30 percent or less on older children. Oil of lemon eucalyptus should not be used on children under three years of age.
• Avoid peak mosquito hours, which occur from dusk to dawn.
• Wear long sleeves, long pants and socks to keep mosquitoes from biting your skin.
• Drain or discard all items that hold water, including buckets, tires, unused flowerpots and wading pools. Check gutters and drains after heavy rain. Change water in birdbaths frequently. Flush out water troughs at least weekly.
• Install or repair tightly-fitting screens on all windows and doors to keep mosquitoes outside.
• Protect your pets and speak with your veterinarian about mosquito repellants that are approved for use in animals, as well as vaccinations to prevent WNV and EEE. Horse owners should keep their horses in indoor stalls at night to reduce mosquito exposure. If an animal is diagnosed with WNV or EEE, owners must report to DAR, Division of Animal Health at 617-626-1795 and to the Department of Public Health at 617-983-6800.

For more information, including all WNV and EEE positive results from 2012, visit the Arbovirus Surveillance Information web page at www.mass.gov/dph/wnv.