Public Health Officials Raise West Nile Virus Risk Threat

Public health officials have raised the risk level of West Nile Virus in the area after a woman in Middlesex County became the second human case of WNV in Massachusetts this year.

The woman, who is in her 40s, was hospitalized and released from the hospital, according to the Massachusetts Department of Public Health.

The DPH raised the risk level to “Moderate” in Melrose, Reading, Saugus, Stoneham, Wakefield, Winchester and Woburn.

“While cooler weather reduces mosquito activity, risk for mosquito-borne illness remains a concern until the first hard overnight frost,” said State Public Health Veterinarian Dr. Catherine Brown. “Residents need to continue to take steps to protect themselves against mosquito bites: use insect repellant, cover up, and avoid outdoor activities at dusk and after nightfall when mosquitoes are at their most active.”

There were eight human cases of WNV in Massachusetts last year, according to the DPH.

“While WNV can infect people of all ages, people over the age of 50 are at higher risk for severe disease. WNV is usually transmitted to humans through the bite of an infected mosquito. Most people infected with WNV will have no symptoms. When present, WNV symptoms tend to include fever and flu-like illness. In rare cases, more severe illness can occur,” said the DPH.

Here are some tips to prevent WNV from the DPH:

Avoid Mosquito Bites

Apply Insect Repellent when Outdoors. Use 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 according to the instructions on the product label. DEET products should not be used on infants under two months of age and should be used in concentrations of 30% or less on older children. Oil of lemon eucalyptus should not be used on children under three years of age.

Be Aware of Peak Mosquito Hours. The hours from dusk to dawn are peak biting times for many mosquitoes. Consider rescheduling outdoor activities that occur during evening or early morning.

Clothing Can Help Reduce Mosquito Bites. Wearing long-sleeves, long pants and socks when outdoors will help keep mosquitoes away from your skin.

Mosquito-Proof Your Home

Drain Standing Water. Mosquitoes lay their eggs in standing water. Limit the number of places around your home for mosquitoes to breed by either draining or discarding items that hold water. Check rain gutters and drains. Empty any unused flowerpots and wading pools, and change water in birdbaths frequently.

Install or Repair Screens. Keep mosquitoes outside by having tightly-fitting screens on all of your windows and doors.

Protect Your Animals

Animal owners should reduce potential mosquito breeding sites on their property by eliminating standing water from containers such as buckets, tires, and wading pools – especially after heavy rains. Water troughs provide excellent mosquito breeding habitats and should be flushed out at least once a week during the summer months to reduce mosquitoes near paddock areas. Horse owners should keep horses in indoor stalls at night to reduce their risk of exposure to mosquitoes. Owners should also speak with their veterinarian about mosquito repellents approved for use in animals and vaccinations to prevent WNV and EEE. If an animal is diagnosed with WNV or EEE, owners are required to report to DAR, Division of Animal Health by calling 617-626-1795 and to the Department of Public Health (DPH) by calling 617-983-6800.

More information, including all WNV and EEE positive results from 2013, can be found on the Arbovirus Surveillance Information web page at www.mass.gov/dph/mosquito or by calling the DPH Epidemiology Program at 617-983-6800.