Stagnant water left from recent rains could become a favorite breeding ground for disease carrying mosquitoes, but some simple practices can keep you safer.

Since the outbreak of West Nile virus in Louisiana in 2002, LSU AgCenter scientists have been on the lookout for ways to keep mosquito numbers down and have enlisted the public’s help in the process, according to LSU AgCenter entomologist Tim Schowalter.

“We know that mosquitoes use standing water sources as their primary breeding areas. So if we can make sure that they are denied these areas, we will be able to decrease their numbers,” he said.

It normally takes about two weeks for mosquitoes to go through their breeding cycle in standing water, and then they become the biting pests that are both feared and hated.

“Of the nearly 70 species of mosquitoes found in Louisiana, there are only about 10 that we as humans have to worry about,” Schowalter said.

The tropical and subtropical climate in Louisiana allows mosquitoes to be active year-round which increases the chance of being bitten.

“The female mosquito must have a blood meal from a human or animal, often a bird, before they can lay eggs,” Schowalter said. As they move among these hosts taking blood, they also may be spreading viruses and other agents that can cause diseases.

Several mosquito-borne diseases are found in Louisiana, including St. Louis encephalitis, eastern equine encephalitis, LaCrosse-California encephalitis and most recently, West Nile virus.

Though West Nile cases in humans have decreased in the past few years, this does not mean that the virus is not still here, Schowalter said.

The disease does not cause most people to become seriously ill.

“People over 50 years of age or with impaired immune systems are most likely to develop serious illness from the disease,” Schowalter said.

Symptoms occur three to 15 days after the initial infection and can range in mild cases from slight fever to headaches to extreme cases that can result in paralysis or death.

“We did see a die-off of the most susceptible reservoir birds like crows, which are now making a comeback,” he said.

Other animals susceptible to the virus include horses, squirrels, domestic rabbits, bats, chipmunks, skunks and alligators.

The number of cases in horses has steadily decreased since the development and widespread use of an effective equine vaccine.

Wild birds are a good indicator for West Nile activity in an area, said LSU AgCenter entomologist Lane Foil.

“They serve as a source of information, and most aren’t affected by the virus,” Foil said.

A number of ways to reduce the mosquito population include:

– Remove containers that hold standing water, such as old tires and other debris.

– Empty flower pots and other yard and patio containers.

– Drain fountains, ornamental ponds and swimming pools no longer being properly maintained or treat with Bt discs (a bacterial pathogen of mosquito larvae).

– Fill low-lying areas to avoid standing water.

– Provide drainage ditches to promote rapid runoff of rainwater.

Johnny Morgan