Michigan West Nile Virus Update: Total Human Cases 417

October 11, 2002

The Michigan Department of Community Health today announced 8 new cases of West Nile virus disease in humans, for total of 417 probable and confirmed cases in Michigan.  The total number of deaths in Michigan associated with West Nile virus disease remains 28. 

“Mosquito activity, although somewhat decreased with the cooler whether, is still on-going, and may continue for several weeks,” said Department of Community Health Chief Medical Executive, David R. Johnson, M.D.  “Until mosquito activity and the risk of West Nile virus transmission end with considerably colder whether, we all must continue to reduce or eliminate our exposure to these insects.”

Individuals with fever and signs of encephalitis and/or meningitis should be tested for West Nile virus.  Symptoms of encephalitis (inflammation of the brain) and meningitis (inflammation of the spinal cord and brain linings) include severe headache, stiff neck, stupor, disorientation, coma, tremors, muscle weakness, convulsions and paralysis.  Physicians are also urged to test patients for West Nile virus if they present with sudden, painless paralysis in the absence of stroke.

Case information can be found at http://www.michigan.gov/mdch and by clicking on “West Nile virus.”  The cases are as follows:
· Macomb County has 1 new case, for a total of 62 cases. 
· Oakland County has 5 new cases, and a previously reported case in Macomb County has been determined to be an Oakland County case, for a total of 149 cases.
· Wayne County has 2 new cases for a total of 133 cases.
· Ingham County has 6 previously reported cases.
· Kalamazoo County has 2 previously reported cases
· Kent County has 47 previously reported cases.
· Lenawee County has 2 previously reported cases.
· Ottawa County has 6 previously reported cases.
· St. Clair County has 2 previously reported cases.
· Arenac, Bay, Cass, Eaton, Muskegon, Newaygo, Otsego and Van Buren Counties all have 1 previously reported case. 

Although on-going investigations demonstrate that the virus may rarely be transmitted to recipients of organ transplants or blood transfusions, it is well documented that West Nile virus is spread to humans by infected mosquitoes and is NOT transmitted from person-to-person, horses to people, or birds to people.  People cannot get it from touching or kissing others who have the virus or from a health care worker who has treated someone with it.  There are many ways to reduce the risk of becoming infected, including:

· Applying insect repellant that contains the active ingredient DEET to exposed skin or clothing, always following the manufacturer’s directions for use on the label.
· Maintaining window and door screening to keep mosquitoes out of buildings.
· Draining standing water in the yard.  Empty water from mosquito breeding sites, such as flower pots, pet bowls, clogged rain gutters, swimming pool covers, discarded tires, buckets, barrels, cans and similar sites in which mosquitoes can lay eggs.
· Avoiding or minimizing outdoor activity at dawn, dusk and early evening when mosquito activity is high.  If outdoors, wear light colored long-sleeved shirts and long pants.

Blood, organ, tissue and bone marrow donation do not pose any risk of West Nile virus to the donor.  Information on organ donation can be found at http://www.giftoflifemichigan.org and blood donation information can be found at http://www.semredcross.org/.

For communities considering additional mosquito control efforts, the Michigan Departments of Agriculture and Community Health recommend the following:
· Involve the community as much as possible in the development and implementation of additional mosquito control efforts. 
· Visit the Department of Agriculture’s web site at www.michigan.gov/mda for a list of vendors licensed and certified to do mosquito control work.  Contact the Pesticide and Plant Management Division (517-373-1087) or the nearest MDA regional office for further information or for assistance in developing comprehensive and integrated plans.
· Use the lowest volumes, lowest concentrations of the least toxic mosquito control products that will be effective.
· For controlling mosquito larvae, focus on standing water that cannot be drained (e.g., catchment basins).
· For controlling adult mosquitoes, focus on community green spaces (e.g., cemeteries, parks, golf courses) at nightfall and in the absence of human activity.
 
West Nile virus has been detected in birds in 71 counties and in 145 horses in Michigan.