The latest victim is a 54-year-old Boulder County resident; the earlier victims live in eastern and northeast Colorado.
No cases have been reported to date in San Miguel County.
Hoping to keep it that way, San Miguel County is running a series of “Fight the Bite” ads and County Nursing Director June Nepsky and staff are regular features at the summertime Farmers Market, held Friday afternoons, on South Oak St., handing out “little bags that have information about how to avoid West Nile,” she said, and free samples of DEET.”
As we head into the dog days of summer, the West Nile threat is heightened, Nepsky emphasized, to which end “elderly people” (in medical parlance, Nepsky said, that means “anyone over 50”) who go out after 5 p.m. at night “need to apply their DEET, because they are more prone to severe effects of West Nile.”And while West Nile is transmitted from birds to mosquitoes – “the mosquito is a vector,” Nepsky explained, transmitting the virus from infected birds to humans, “it’s just one of those viruses,” Nepsky said, “that’s carried by mosquitoes,” along the lines of dengue fever and malaria.
2007 a ‘High Risk Year’
“Based on the surveillance data from around the state,” however, “the indicators are suggesting that we're heading into a high-risk year,” said John Pape, an epidemiologist with the state Department of Public Heath and Environment.
The number of Culex mosquitoes, which transmit the disease, is “extremely high for this time of year and rising rapidly,” he said.
Counts of the Culex mosquito, which carries the disease, are the same or higher this year than in 2003, when West Nile killed 63 people in Colorado and was diagnosed in nearly 2,900 others.
Infected mosquitoes have been found in Boulder, El Paso, Jefferson, Larimer, Logan, Mesa, Otero, Prowers and Weld counties, health department officials said. A wet spring, a rainy start to the summer and hot weather makes it possible for the mosquitoes and the virus to develop faster, said Melina Hogan, a health department epidemiologist.
Health officials expect more human cases because they began discovering infected mosquitoes earlier than usual. Already, 26 groups of mosquitoes have tested positive, with 18 of those detected since July 1.
Normally, infected mosquitoes would only now be starting to turn up.
“This is the time [for people] to start protecting themselves. This is the time to start using insect repellent with DEET and also try not to be outside at times of dusk and dawn,” Hogan said.
Health officials said the total number of human cases is much higher than what is reported because only a small proportion of people who are infected feel sick.
Symptoms include fever, headache and neck stiffness. In more serious cases, blindness, paralysis and inflammation of the brain have been reported.
This year's victims in Colorado have also included a 51-year-old who lives in Logan County and a resident of Cheyenne County.
Utah Mosquito Cluster Tests Positive for West Nile
In Logan, Utah, a cluster of mosquitoes in Box Elder County has tested positive for West Nile virus, marking the emergence of the disease in northwestern Utah, the Bear River Health Department confirmed the test results Friday.
It was the year's second confirmed case in Utah of a disease that can be spread by mosquitoes that pick it up from biting infected birds.
Earlier one of the more than 400 chickens distributed to communities across Utah for testing purposes was confirmed to have the virus. The chickens don't get sick from the virus but develop signs of infection in their blood.
The U.S. Centers for Disease Control and Prevention said there were 158 human cases of West Nile, including five deaths, in Utah in 2006.
Most people infected with West Nile show no symptoms, but some can develop a fever, headache and rash that lasts a few days, experts say. Older people are at greater risk.
The Bear River Health Department is advising people spending time outdoors to wear long sleeves and pants, use bug spray containing DEET, drain any standing water around homes and replenish water in bird baths every few days.
Box Elder County authorities said they would be spraying larvacide and insecticide from truck-mounted foggers throughout the summer.
Nationally, last year was the worst year for West Nile since 2003, with at least 177 deaths reported. The deadliest year for West Nile was 2002, when 284 people died.