Rains could mean return of West Nile Virus

Dave Brooks

The bugs are coming.

Health officials are worried that this winter’s record rainfalls

could bring a dramatic increase in the local mosquito population and

an outbreak of the West Nile Virus.

Mosquito populations are already up substantially from last year

when 64 people became infected with West Nile and another four died,

said Mike Hearst of the Orange County Vector Control Agency, the

group responsible for monitoring the insect. Hearst said the mosquito

season, which usually doesn’t begin until mid-spring, is well

underway and health officials are finding cases of West Nile months

ahead of when they normally surface.

“We’re expecting a pretty a severe mosquito season, there’s no way

around that,” Hearst said. “What we’re not sure of is how that

translates into West Nile.”

Health officials have already found two dead birds in Orange

County with the disease. No human cases have been reported locally,

but one person in Los Angeles County has been diagnosed with the

disease.

West Nile first reached the West Coast about two years ago and is

spread to humans by mosquitoes, which contract the virus by feeding

on infected birds.

“The count’s are pretty significant,” Hearst said. “We’re finding

the same number of mosquitoes in February that we wouldn’t normally

find until March.”

Mosquitoes need only seven days to hatch in still water. Hearst

said the heavy rains have made puddles out of everything, from an

empty tire to a low point in a backyard, and many urban areas could

become breeding grounds for the bugs.

“People are concerned about the wetlands and marshes, but those

are areas we already know about,” he said. “One of the biggest

problem areas is backyards, areas that collect water.”

Vector control agents regularly spray for West Nile Virus and trap

and test birds at a number of locations throughout Orange County,

including a site on the south end of the Bolsa Chica wetlands.

Doctors are also required to report the disease to health officials

whenever someone is diagnosed with West Nile.

“Symptoms only show up in about 15% to 20% of those infected, so

there could be a lot more people walking around with the disease than

we realize,” said Vector Control agent Robert Cummings. West Nile is

usually only fatal in elderly victims and individuals with weak

immune systems.

To help prevent the spread of the disease, Howard Sutter of the

Orange County Health Care Agency said, residents need to be diligent

about draining standing water.

“The key to reducing the number of cases of West Nile is to reduce

the local mosquito population,” he said.

Hearst is encouraging residents to report problems with standing

water and call Vector Control at (714)971-2421 if they come upon any

dead birds.

Residents should also check to make sure all their screen windows

are secure, Sutter said. When outside, use insect spray and wear

clothes with long sleeves.

“Also, try to reduce outside activity during dusk and dawn

periods,” he added. “That’s when mosquitoes are most active and

looking to bite.”