Watch for Island Closings Caused by Newcastle Disease in Minnesota
Don’t be too surprised if you see “closed” signs on certain islands and lake access points within five Minnesota lakes. Birds from these lakes were confirmed to have virulent Newcastle disease, according to the Minnesota Department of Natural Resources (DNR).
The virus, which already has killed more than 1,200 double-crested cormorants this summer in Minnesota, has been confirmed at Minnesota Lake, Pigeon Lake, Lake of the Woods, Marsh Lake and Lake Kabetogama. DNR officials still are waiting for results from Mille Lacs Lake.
Counties affected or potentially affected by the closed areas include Meeker, Faribault, Mille Lacs, Cass, St. Louis (in the Voyageurs National Park area), Lake of the Woods and Lac Qui Parle. Closed areas should be signed by the end of the week.
The disease can be transmitted via contaminated clothing and equipment, and infected birds can spread the virus through direct contact as well as through their feces and excretions. Newcastle disease is not a major concern for humans, although it may cause a mild conjunctivitis and influenza-like symptoms.
Clinical signs of Newcastle disease in avian species are frequently neurological, such as droopy heads and paralyzed wings and legs. Nestlings and juveniles birds are most commonly affected. Mortality rates in wild species can vary greatly, with double-crested cormorants most commonly affected.
No cases of Newcastle disease outbreaks in wild species were reported until 1990 in the United States or Canada. In 1992, more than 35,000 double-crested cormorants died from the virus across the Great Lakes, Upper Midwest and Canada. Sporadic outbreaks in cormorants have been reported since 1990 in California, Utah, Nevada and Oregon.
DNR wildlife staff is working with the National Wildlife Health Center, the National Park Service, the U.S. Department of Agriculture, the Minnesota Board of Animal Health, the U.S. Fish and Wildlife Service, the Mille Lacs Band of Ojibwe, and the Canadian Cooperative Wildlife Health Centre to manage the outbreak by reducing possible impacts to other wild birds and prevent spillover of the disease into domestic poultry.