Last Modified: Sunday, September 16, 2012 7:32 PM
JENNINGS — The Jefferson Davis Parish Mosquito Abatement District is aggressively working to diminish the mosquito population in the parish in response to West Nile cases across the state.
There have been 176 cases of West Nile reported in Louisiana so far this year, with 10 cases resulting in death. Nationally, there have been 1,993 cases of West Nile reported and 87 deaths from the virus.
No cases of West Nile virus have been reported in humans in Jefferson Davis Parish, although eastern equine encephalitis has killed one horse and is suspected in the death of another in the parish.
For the most, mosquitoes never really go away in Louisiana because of wet conditions, Jefferson Davis Parish Mosquito Abatement District Director Curt Bowers said.
“We can never get rid of the mosquitoes, because we have breeding grounds for them. But by the numbers we are collecting, compared to the early ’80s when the district started, we are about 10 percent of what we use to see,” he said.
In Jefferson Davis, the mosquito population is a problem because of the nearly 100,000 acres of flooded rice field, 60,000 acres of crawfish ponds and 40,000 acres of fields that are flooded for hunting.
A rice field can produce a million mosquitoes, under ideal conditions, he said.
“We are wet year round,” Bowers said.
He said the district has been busy battling mosquitoes since March.
“It has been an unusually busy season, but we are trying to keep the disease threat down,” he said. “Our first responsibility is disease response. Our second priority is to provide comfort to the public and the third priority is to protect the animals.”
Major events like a hurricane can take 7-10 days to bring the mosquito population back down to a tolerable rate. Bowers said the district was back spraying two days after Tropical Storm Isaac.
Frequent aerial and ground spraying can control adult mosquito populations, but often take time, he said.
“The insecticides we use don’t create a residue so it has to be sprayed directly on the mosquito to be effective, so many times it can take several times ’til we get the mosquito population down,” he said.
It cost the district about $25,000 a night to operate.
The district maintains 21 collection and 70 monitoring sites throughout the parish.
For the month of August, 44,872 mosquitoes were collected, which is about 2 percent more than the previous year’s collection for August, he said.
The highest mosquito population was in the northeast quadrant of the parish in the Elton area, where 7,739 mosquitoes were collected. The lowest population was reported east of Welsh with 631 mosquitoes collected.
The highest single night collection was Aug. 27, when 11,916 mosquitoes were collected parishwide.
The district also has rain gauge collection sites and records the amount of rain received, which is an important factor in the number of mosquitoes produced, Bowers said.
“In August we had rainfall reported at just about every collection site,” he said. “On the 20th of the month we had in excess of 2 1/2 inches parishwide and ended the month with a total of nearly 9 inches.”
The rain resulted in an increase in mosquito population, he said.
The parish has 32 species of mosquitoes with 64 species reported statewide. Each mosquito is different in character, habitat and flight range, he said.
“And they are all not carriers of disease,” he said. “Some are just a nuisance.”
The biggest portion of mosquitoes in Jefferson Davis Parish are considered nuisance pests and do not carry diseases, he said.
“The problem is it only takes one bite from a vector mosquito to transmit a disease,” he said. “We will never get rid of all the mosquitoes, but we can control them.”
The mosquitoes can carry the West Nile virus from birds to humans and other animals, including horses. Vaccines are available for animals and is strongly encouraged, he said.
Once bitten by an infected mosquito, it can take up to two weeks for the infection to develop and symptoms to appear, Bowers said. Symptoms include muscle weakness, stiff neck, confusion, fever, headache, joint pain and nausea.
Residents are urged to take preventive measures to protect against West Nile virus. These include applying insect repellent, wearing protective clothing and draining any standing water that serves as breeding grounds for mosquitoes.
Residents can also request mosquito service by calling the district at 824-4040. Requests are handled within 24-48 hours.