Mich. blood donor tests positive for West Nile virus
A Michigan blood donor tested positive for West Nile virus Tuesday, the first confirmed human infection this year, health officials say.
The Michigan Department of Health and Human Services said the blood donor tested positive for the mosquito-borne virus in Sanilac County, north of Macomb.
“This is an important reminder to stay vigilant and protect against mosquito bites throughout the summer and into the fall,” said Dr. Eden Wells, MDHHS chief medical executive. “Residents should use insect repellent, drain standing water around the home and take extra care during peak mosquito-biting hours between dusk and dawn.”
Mosquito bites are the main cause of human infections in Michigan. The insects become infected with West Nile virus when they bite an infected bird. As of Tuesday, 20 birds and 24 mosquito pools have tested positive for West Nile Virus around the state, according to the health department.
The virus was detected in Oakland County mosquito pools in June, although there have been no reported cases there of human infection. Outbreaks of have been occurring every summer since 2002. Macomb, Oakland, Wayne and Kent counties have historically seen the most activity.
Officials said blood donations are regularly screened for West Nile prior to distribution, and donations that test positive are discarded and not used for transfusions.
Currently, the donor is not reporting any illness. Most people who become infected will not develop any symptoms; however, some become sick three to 15 days after exposure.
About one in five infected persons will have mild illness which may include fever, headache, body aches, joint pain, vomiting, diarrhea or rash. About one in 150 infected people will become severely ill. Severe symptoms are associated with encephalitis or meningitis, and may include a stiff neck, stupor, disorientation, coma, tremors, muscle weakness, convulsions and paralysis. People 60 and older are more susceptible to severe disease symptoms, according to the health department.