BRODIE FARQUHAR Star-Tribune staff writer | Posted: Friday, April 25, 2003 12:00 am
Wyoming Department of Health officials Thursday announced the start of surveillance activities for West Nile virus (WNV) for 2003 and unveiled a new Web site and a toll-free number for public education.
"We want the public to contact us directly," said Terry Creekmore, the West Nile virus surveillance coordinator for the Wyoming Department of Health. Last year, concerned citizens were calling their public health or mosquito control officials when citizens found dead birds, he said.
The state will begin testing only crows, magpies, jays, and ravens from May 1 through October. Those with dead birds for testing should call the toll-free number, (877) WYO-BITE for instructions on how carcass(es) should be transported to the laboratory. The Web site (www.badskeeter.org) may also be accessed.
Creekmore says carcasses must be handled with gloves or with plastic bags placed over hands. The birds should then be double-bagged with an ice pack if available and placed in a cool place - but not in a refrigerator or freezer.
Creekmore said the Wyoming vector for the disease is the Culex species, which has a few adults that will successfully overwinter. Creekmore expects the Culex mosquitos to immediately start feeding on fledgling birds in May. Culex populations peak from late August through mid-September, he said, which is when Culex mosquitos will feed on large mammals, such as horses and people.
The first, big hatchings of mosquitos in Wyoming are typically the Aedes species, which has not yet been proven to be a West Nile virus vector, Creekmore said. "I expect to see them in late June," Creekmore said.
The key to how soon the general public will notice mosquitos hatching is water temperature, Creekmore said. Mosquito larvae need a certain water temperature to develop and hatch, he said. Proper temperatures can allow quick development from egg to adult, about one week, while cooler water can delay the process.
West Nile virus is historically found in portions of Africa, the Middle East, and Central Europe. In 1999, WNV invaded New York City and has since spread to all but four states in the continental United States. Nationwide last year 4,161 people became ill and 284 people died from WNV infection. However, less than 1 percent of the people infected with WNV become seriously ill. About one-third of the people infected develop flu-like symptoms while the majority of people never get sick. Two nonfatal human cases were reported in Wyoming last year, but the number of human infections will likely increase as the virus continues to expand throughout the state, said Creekmore.
Last year, the state public health lab tested 90 human cases with two positives; the state veterinary lab tested 342 horses with 96 positives and 273 birds with 20 positives.
The "Bad Skeeter: Prevent West Nile Virus" education campaign this year is pretty ambitious, said Ross Doman, public information officer for the department of health. Doman said brochures and pamphlets will be available soon.