February 27, 2006

Louisiana seen facing post-Katrina mosquito boom

By Kevin Krolicki

DETROIT (Reuters) - Louisiana, struggling to rebuild from
Hurricane Katrina, now faces a potential scourge of mosquitoes
as insects hatch in storm-created breeding grounds, scientists
said on Monday.

The expected surge in the mosquito population this summer
around New Orleans raises worries about the risk of an
accompanying increase in cases of the mosquito-borne West Nile
virus, public health officials said.

"The mosquitoes have just taken off," said Janet
McAllister, an entomologist with the Centers for Disease
Control and Prevention.

McAllister was one of several officials who spoke at a
Detroit meeting of the American Mosquito Control Association,
where a special session was devoted to the government response
to hurricanes Katrina and Rita.

In New Orleans, officials are trying to combat an influx of
salt-marsh mosquitoes in thousands of abandoned and damaged
swimming pools in the city's backyards through an improvised
program of "pool patrols," McAllister said.

The problem has been compounded by the relatively warm
winter in New Orleans, said McAllister, a native of New Orleans
who worked in the city's insect control program before joining
the CDC.

North of New Orleans, downed trees are blocking drainage
channels, and marsh plants churned up by the autumn hurricanes
have created new breeding grounds for mosquitoes, said Chuck
Palmisano, director of mosquito abatement in St. Tammany

"We still don't know what this is going to mean, but we
believe it is going to increase breeding," said Palmisano.

Meanwhile, massive trailer parks set up for Katrina
refugees pose new problems, said Randy Vaeth, a biologist who
works for East Baton Rouge Parish.

Public health officials have no good way of notifying the
residents of the trailer parks that they are planning to spray
pesticides and to warn them to stay indoors, he said.

In addition, wastewater treatment plants set up to deal
with the thousands of displaced residents are proving to be
rich mosquito breeding grounds, he said.

McAllister said hastily organized U.S. Air Force flights to
spray insecticide to control mosquitoes and to kill the "filth
flies" breeding in New Orleans garbage heaps were a rare
success amid the chaos that followed Katrina.

The first time a specially outfitted C-130 transport
sprayed insecticide over the French Quarter in mid-September
"the flies were literally raining out of the sky on us," she

Louisiana has a long history with mosquito-borne illnesses.
New Orleans, which borders on marshes and brackish Lake
Pontchartrain, was the site of the last yellow fever epidemic
in the United States in 1905.

The first statewide effort to control the insects began in
the mid-1950s when New Orleans residents complained about the
health risk from ferocious mosquitoes in city neighborhoods.