The spate of flood-inducing rain that has struck Iberia Parish within the past couple of weeks has the Iberia Parish Mosquito Abatement District on the move.
“We are seeing some increases in populations due to the high rains we’ve been having,” said Herff Jones, director of the district.
Jones said remaining floodwaters seem to have produced an increase in mosquito populations particularly in the western — Coteau area and Delcambre — and the southern — Port of Iberia area — portions of the parish. The district responded by having aerial spraying over those areas Friday and Saturday.
The weather following the heavy rains likely exacerbated the situation, Jones added.
“The hotter and more humid it is, the quicker they go from egg to adult,” he said.
To no surprise, the population of “floodwater nuisance mosquitoes,” which includes a variety of medium-to-large brown breeds with extremely large flight radii (up to 20 miles, Jones said), has swelled. Fortunately, these breeds are more annoying than dangerous and aren’t known to transmit anything except itchy bumps when they bite.
However, mosquito traps also have been capturing higher numbers of Southern house mosquitoes and Asian tiger mosquitoes, both of which are known disease carriers and transmitters.
Southern house mosquitoes, or “quinks” as Jones called them, are medium-sized and brown and have a flight radius of around a mile from their birth site. These are the breed associated with the transmission of encephalitic diseases — such as the West Nile virus, Saint Louis encephalitis and eastern equine encephalitis.
“We’re very concerned about that,” Jones said. “When these numbers escalate, we want to use our ground and our air options to eradicate them.”
Encephalitic diseases cause acute brain inflammation, with variants like West Nile being potentially fatal. A Shreveport man died last week of West Nile virus, marking the state’s first death from the disease this year.
According to the Louisiana Department of Health and Hospitals, there have been seven human cases of West Nile virus in the state so far. Its website, which regularly updates data on the virus, said around 90 percent of all infections are asymptomatic, with the remaining 10 percent developing the West Nile fever that has potential to become dangerous or even fatal.
None of the human cases have been in Iberia Parish.
“That’s not to say we should have any relax in our operations,” Jones said.
Asian tiger mosquitoes, small and black with white or silver spots, are weak fliers and will remain within the immediate vicinity of where they hatch, normally near homes.
“They’re active pretty much all day,” Jones said.
This breed has been shown to carry encephalitic diseases, but not to transmit them. However, Asian tiger mosquitoes are considered primary transmitters of diseases like dengue fever and chikungunya, which both typically cause muscle and joint pain and create a large skin rash.
Future aerial spraying — which, like truck spray on the ground, uses pesticides to kill populations — will depend on where populations surge and whether tests indicate disease in a particular area.
“If this rain pattern continues, we expect it (population growth) to be widespread throughout the parish,” Jones said.
Residents should take steps to remove standing water from their properties, especially if the water is “organic,” or contains decomposing plants and animal waste. A container as small as a water bottle cap is enough water for mosquitoes to breed, Jones said.
It is recommended to wear light-colored and long-sleeved clothing when in high-population areas and insect repellent should be regularly used outdoors.
Additional information or data on disease spread can be found on www.new.dhh.louisiana.gov, which also lists safety tips for venturing outdoors. Inquiries on local mosquito control can be made at 365-4922 and more information is provided at www.IberiaParishGovernment.com.dept-mosquito.asp.