MARSHALL - A Murray County man has been inflicted with the first human case of West Nile Virus of 2013, the Minnesota Department of Health said Thursday.
The man became ill with WNV fever earlier this month and is recovering, the MDH said. The MDH?would not say what city he is from.
David Neitzel, an MDH epidemiologist specializing in diseases carried by mosquitoes, said the man's condition was not serious enough for hospitalization.
"It was the less severe form of the disease," Neitzel said. "I don't want to downplay this case at all, but it wasn't life-threatening and didn't affect his nervous system like other cases. It's still a bad illness, but it wasn't the life-threatening form."
State health officials are urging Minnesotans to protect themselves from mosquitoes. West Nile virus is a potentially life-threatening disease and Minnesotans should protect themselves by routinely using mosquito repellents and taking other simple precautions against mosquito bites, MDH officials say.
Neitzel said that Minnesota has entered the high risk season for WNV which continues through early autumn. Neitzel said the state is on alert for WNV now more than ever since last year's outbreak that resulted in 70 cases and one fatality. He said last year's weather played a major role in that outbreak.
"Last year we didn't have much of a winter, and we had a warm spring and then it got hot and dry, so there was a high risk," he said. "This year, the late spring should help us. We have a shorter growing season for the virus and mosquitoes. Unfortunately, there's enough warmth and enough mosquitoes that we are going to see some cases this year."
"The species of mosquito that transmits the virus to humans is most abundant in July and August. Mosquito repellents used during outdoor activities at dusk and dawn can prevent this potentially severe disease," Neitzel said in a news release.
This is the third reported case of WNV in the area in the last three years.
In 2010, Jerry Livermore of Clarkfield spent more than 40 days in intensive care at the Mayo Clinic after being stricken with a severe case of West Nile. Livermore came down with a staph infection and pneumonia.
In all, Livermore was hospitalized for four-and-a-half months; he also underwent another five months of rehab in Marshall.
On Aug. 10 of last year, Norma Renken, who lives on a farm near Arco, was admitted to Avera Marshall Regional Medical Center with a severe case of West Nile.
About 1 out of 150 people bitten by a WNV-infected mosquito will develop central nervous system disease (encephalitis or meningitis). Approximately 10 percent of people with this severe form of infection die from their illness, and survivors can suffer from long-term nervous system problems. Most people bitten by infected mosquitoes develop West Nile fever, the less severe form of disease, or fight off the virus without any symptoms.
Illness from WNV can occur in residents throughout Minnesota and among all age groups, but WNV risk is greatest in western and central counties, which typically have the greatest number of Culex tarsalis mosquitoes, the primary mosquito carrier of the virus in Minnesota, the MDH said. Culex tarsalis mosquitoes, which carry WNV, prefer open, agricultural areas of central and western Minnesota and other Great Plains states.
Elderly people or people with weakened immune systems face the highest risk of developing the more severe or even fatal illness from a WNV infection.
Symptoms of WNV disease usually begin three to 15 days after being bitten and can include headache, high fever, rash, muscle weakness, stiff neck, disorientation, convulsions, paralysis and coma, the MDH said.
There have been 535 WNV cases and 16 deaths attributed to the virus in Minnesota since it was first found here in 2002.