DETROIT -

Michigan health officials say there are now 80 confirmed cases of West Nile Virus and four deaths.

During a conference call Wednesday, the Michigan Department of Community Health said an 86-year-old woman from Wayne County was the latest to succumb to the virus – which is spread by mosquitoes.

The other deaths have occurred in Washtenaw County, Detroit and another in Wayne County.

Dr. Ned Walker, a Michigan State University professor, said research has revealed that certain communities are more vulnerable than others as spreading the virus. He said neighborhoods with post- World War II housing, those built in the 40s and 60s, are likely to be more densely populated and have more catch basins. Walker called the basins “little mosquito factories.”

Examples are Allen Park, Berkley, Royal Oak, Westland, Dearborn Heights, Ferndale, Oak Park and Inkster.

Dr. Dean Sienko, interim chief medical executive at MDCH, said Michigan saw 34 total cases and two deaths in 2011. He said Michigan is experiencing an "epidemic of West Nile virus activity."

This year, warmer spring and summer weather conditions have accelerated the virus activity - which is mostly affecting those over the age of 50.

Michigan residents are encouraged to take the following steps to avoid WNV:

•Apply insect repellents that contain the active ingredient DEET, picaridin, oil of lemon eucalyptus or other EPA approved repellent to exposed skin or clothing.

•Avoid being outdoors at dusk and dawn when mosquitoes are most active.

•Maintain window and door screening to help keep mosquitoes out of buildings.

•Empty water from mosquito breeding sites such as buckets, unused kiddie pools, old tires or similar sites where mosquitoes lay eggs.

•Wear light colored, long-sleeved shirts and long pants when outdoors.

The mosquitoes that transmit WNV to humans lay eggs in small pools of standing water. Adult mosquitoes can hatch in 10 days in warm weather. Mosquitoes become infected and transmit WNV after feeding on birds carrying the virus. Within 10 to 14 days, the mosquito can transmit the virus to humans and horses.

Many of the same precautions people take can also be used to protect livestock:

• Since West Nile Virus is spread to horses through the bite of an infected mosquito, protection measures that reduce the exposure to mosquito bites should be adopted.  

•It is not too late to vaccinate horses this season. Talk to your veterinarian for details.

•Use approved insect repellants to protect horses. If possible, put horses in stables, stalls, or barns, preferably under fans, during the prime mosquito exposure hours of dusk and dawn.

• Eliminate standing water, and drain troughs and buckets at least once a week.

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