Bzzzzt! Ouch! Slap!

Those are common sounds during the summer in St. Tammany Parish as hot weather and a lot of rain bring clouds of mosquitoes into the area.

Mosquitoes are not just a nuisance that cause lots of itching and turn backyard barbecues into times of misery. According to Chuck Palmisano, director of the St. Tammany Parish Mosquito Abatement District, those pesky insects can be carriers of deadly diseases that affect humans, horses, and dogs. The West Nile virus is the most commonly known disease spread by mosquitoes, as well as meningitis, dengue fever, chicken gunya and malaria. Cases of dengue and gunya are just beginning to be seen in the Northern Hemisphere, and malaria, though widespread throughout most of the tropical world, is rare in the United States.

The pariah of our area is the house mosquito.

The biggest threat these days is West Nile virus, a form of meningitis. Though not usually fatal, West Nile has caused brain damage in some patients and even death. Last year, there were 40 cases of West Nile reported in the state.

Mosquitoes catch the West Nile virus by biting infected birds, which are the common carriers of the disease. The infected mosquitoes then bite humans, horses and dogs, spreading the West Nile virus.

Palmisano said controlling mosquitoes in St. Tammany is a year-round job. Because the area is surrounded by marshland and swamps, the job of stopping the pesky biters is a challenge for Palmisano and his crew.

Starting in February, the mosquito hunters go into the swamps to take a population tally of the mosquito larvae.

“That tells us where our problem areas are and where we have to concentrate our spraying,” Palmisano said.

Right now, the Mosquito Abatement District is concentrating on the area between Covington and Lacombe. Using a fleet of six trucks and two airplanes, Palmisano’s crew sprays the area with a chemical that will kill the larvae. The trucks spray the roadside ditches, and the planes spray the marshlands.

Last month, the large amount of rain forced the district to send up their planes to spray 60,000 acres of land between Covington and Lacombe.

The most important part of the district’s job is constant surveillance, Palmisano said. Even the spraying doesn’t get all the larvae, which grow into adult mosquitoes. Palmisano’s crew has to go out and collect mosquitoes. The insects are tested for West Nile. This year, the district tested mosquitoes from 1,350 pools of water around the parish, and 32 of the insects tested positive for West Nile.

“That is not unusual,” Palmisano said. “The virus levels right now are very low, but we want to find the West Nile virus before it spills out into the human population.”

The constant collecting and testing is key to controlling the mosquito population in the parish.

“It gives us precise location of problem areas,” Palmisano said. “Our biggest challenge is keeping the population of the southern house mosquito at low levels,” Palmisano said.

The southern house mosquito is the primary carrier of the West Nile virus.

The district also spends a lot of time trying to educate the public about mosquitoes and West Nile and how citizens can help the parish in keeping mosquitoes down to a manageable level.

The district asks that residents check their houses and property for standing pools of water where mosquitoes can breed.

Empty out pails, garbage cans, and bird baths that may fill with rain water. Empty out flower pot saucers frequently, and clean the gutters so water does not collect in them. Cover boats so they don’t collect rainwater. Don’t keep old tires around; they tend to collect water and are perfect breeding spots.

To protect yourself from mosquito bites and possible infection, Palmisano recommends that screens and windows be repaired to keep the bugs out of houses.

Wear long-sleeved shirts and long pants when walking through areas like woods and marshes. Use insect repellent that contain the chemical DEET during the summer months. Try and not go outside at dawn or dusk, times when there are lots of mosquitoes flying around.

Palmisano said residents should report dead birds to parish officials. If someone finds a dead bird, do not touch or handle it, but contact authorities who will collect the carcass and test it for West Nile.

There are services that people can use to keep their yards mosquito-free. Companies like MosquitoNix put misters in a resident’s yard that are attached to a large tank of pyrethrine, a mosquito poison. The misters are put on a timer, and the yard is sprayed at various times of the day and night.

Palmisano and Joe Conlon, technical advisor for the American Mosquito Control Association, understand the lure of the misting services, but they do not recommend them for several reasons.

“They are not compatible with our system because they do not have surveillance,” Palmisano said. “The misters spray whether or not there are mosquitoes in the area.”

This presents two problems. First a lot of the poison is put into the air that may affect other living things in the area, and too much of the poison causes mosquitoes to become resistant to the poison, they said.

“Mister systems are seductive because of their low cost,” Conlon said.

However, Ken Davidson, franchise development director for MosquioNix, said his company follows all Environmental Protection Agency guidelines, and the pyrethrine solution they use is “less toxic” to humans than over-the-counter pesticides.

“It is put out in a very fine mist and evaporates quickly,” Davidson said. “Pyrethrine comes from the chrysanthemum flower and has been used for over 100 years.”

He did admit that butterflies, ladybugs and other insects that are not harmful may be killed by the misters.

Still he said, the misting system provides an “impenetrable fortress” to mosquitoes. He added that MosquitoNix is eco-friendly, and the workers are trained on toxicity and the environment.

“I have a system, it works and is perfectly safe for my daughter,” Davidson said.

Conlon said misting system companies don’t follow up with surveillance of mosquito larva population, and the systems work indiscriminately in their operation, not taking into account the life cycle of mosquitoes and the use of pesticides.

“I understand why people want them, but they are not the silver bullet to the problem,” Conlon said.

For more information on protection from mosquitoes and West Nile virus, call the St. Tammany Parish Mosquito Abatement District at 643-5050 or 893-0818.