June 13, 2008

Mosquito-Eating Fish Used in Pools of Foreclosed Homes

Public health officials in Arizona are implementing a program that targets the pools of foreclosed or abandoned homes to fight the outbreak of West Nile Virus.

The program, initiated in Maricopa County, which includes the cities of the Phoenix valley, involves the breeding of tiny silvery fish, which have earned the name "mosquitofish."

After breeding, these fish are distributed to homes with unkempt pools where they go to work by eating larvae that thrive there.

"The abandoned pools become a stagnant little swamp that breeds mosquitoes in the middle of a neighborhood," said John Townsend, Maricopa County Vector Control manager.

"It is an important public health issue to keep the mosquito population down ... and the fish are very effective at that," he added.

The dry Maricopa County region has thousands of pools, but also has one of the highest foreclosure rates in the U.S.

In the first three months of the year, 17,214 homes in Maricopa County were offered for foreclosure sales, a more than three-fold rise on the previous year, according to RealtyStore.com.

West Nile Virus is a seasonal, potentially dangerous illness. About one in 150 people infected with the virus will develop severe symptoms, which include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis. Approximately 80 percent of people (about 4 out of 5) who are infected with the virus will not show any symptoms at all, according to the Centers for Disease Control.

In addition to the added number of foreclosed homes, an unknown number of local homes were simply abandoned as the owners skipped out on their spiraling debts, many leaving untreated backyard pools to stagnate, local authorities say.

Townsend said the county has begun a program to breed 40,000 mosquitofish this year using tanks at Phoenix Zoo. The minnows will be available nationwide.

"Chlorine is not effective as it is burned off by the sun in a couple of days, and we would have to go back and treat it again," said Daniel Anderson, a city official in Chandler.

"Once these fish are in the pool, we are not concerned about mosquitoes until someone either buys the house or the pool dries up."


On the Net:

Centers for Disease Control