West Nile season is over

Nov 032003
Authors: Seth Davis

Richard Bowen spends his days working with chickens, cows,

horses and various other animals.

He is not running a ranch, though; he is helping to protect

people and animals from the West Nile virus.

Bowen, a biomedical sciences professor at CSU, is working with

other researchers to find a vaccine for West Nile by examining how

the disease infects and affects animals.

“Starting back in 2000, we began testing horses, cows, bats,

birds, you name it. We do vaccine testing, trying to understand the

disease in animals,” Bowen said. He said a lot of his work is in

collaboration with the Centers for Disease Control and


While much of the country has experienced the effects of West

Nile, Colorado was hit the hardest. Statistics on the CDC Web site

show that for the year 2003, Colorado had 2,170 human cases of West

Nile compared to the next highest state, Nebraska, at 1,540.

Larimer County accounted for 525 of the human West Nile cases in


Bowen discussed what it was like to be in the middle of all the


“We certainly got a lot of calls,” Bowen said. “I suppose you

could say we were an epicenter for the disease. We knew of it

before it hit Colorado, so that might have helped us prepare for


Anne Watson is a health education supervisor for the Larimer

County Department of Health. She explained why there was such an

explosion of Colorado West Nile cases.

“Weather conditions were perfect for mosquitoes this year,”

Watson said. “We had a warm, mild winter and a wet spring.

Mosquitoes woke up earlier and began biting people and animals

earlier.” She said Colorado had a 30-year high in its mosquito

population in 2003.

A news release from the Colorado Department of Public Health and

Environment declared the West Nile season over for Colorado. Colder

temperatures and less daylight mean the mosquitoes will not be

active again until late May or early June 2004.

In looking ahead to next summer, Bowen said he does not foresee

an increase of West Nile cases in Colorado.

“I think the typical pattern is there’s a small incursion in the

first year. In the second year, the experience has been that it’s

not as bad. One reason is that there is a buildup of immunity in

the population. It also depends on the number of mosquitoes. This

year we had an inordinately large population of mosquitoes compared

to the last 10 years,” Bowen said.

Watson said she knows people are aware of the dangers posed by

West Nile, but not many of them actually seem to care.

“I think they certainly are aware that we had a lot of people

infected,” Watson said. “Of the people who were infected, we did a

case study and found very few of them were using repellant. It’s

kind of like people don’t think it will affect them. Some people

do, but something like 12 percent of infections had been using

repellant regularly.”

While health officials nervously anticipate the next West Nile

season, Bowen will remain busy with his attempts to protect humans

and animals from the disease.

“There is a lot of need for vaccines that will protect humans

and animals from West Nile,” Bowen said.





 Posted by at 5:00 pm

Sorry, the comment form is closed at this time.