home

200

mosquitoes a minute. That’s what an entomologist counted on his body in Lowland earlier this week.

It confirms what has been in the air in much of Pamlico County since Hurricane Irene: the mosquitoes are out in numbers. Big numbers. For the Centers for Disease Control that’s the evidence it needed to approve aerial spraying over parts of the county.

Pamlico County’s Health Director Davin Madden said late Wednesday that the spraying is now set for next Monday night, September 19. Getting the CDC to approve it was just one hoop to jump through, however.

Madden was working in recent days to get several state agencies – Marine Fisheries, Wildlife Resources, Department of Agriculture — to sign off on the plan to spray approximately 85,000-90,000 acres, including Lowland, Hobucken, Mesic, Florence, Whortonsville and Kennel’s Beach.

Concern About Public Health: The Numbers

In an interview with TownDock.net on Wednesday, Davin Madden said that the entomologist sent out earlier this week sighted two species of mosquito — Ae sollicitansand Ae taeniorhynchus. They are, he says, transmitters or “vectors” of Triple E — Eastern equine encephalitis.

Madden says that The Centers for Disease Control considers 20 mosquitoes a minute to be a concern about spreading disease. What entomologist Bruce Harrison found a few days ago soared far above that.

Watching as the mosquitoes flocked to him — and his khaki clothing — the lowest count Dr. Harrison found was 31. The average from all of the places in Pamlico County that he went to was 70-80 per minute. In Lowland things went off the chart: 200 counted in a minute, or 10 times the CDC’s threshold.

There have been no reported cases of Triple E — which despite the word “equine” in its name is not limited to horses but can spread to humans. It’s the increasing numbers of that mosquito transmitters that is the cause for concern. Davin Madden says he doesn’t want an outbreak.

Pamlico County encompasses approximately 566,000 square miles of which 200.000 is underwater. The acreage to be sprayed — about 85,000-90,000 acres — works out to 140 square miles.

The areas to be sprayed are mainly along or not far from the Bay River — the communities of Florence, Whortonsville, Vandemere, Mesic and further up Hiway 304, Lowland and Hobucken on Goose Creek Island. Also in for the crop duster style spraying, says Madden, will be an area north of Kennel’s Beach.

Just Add Water

Most of those areas have a mosquito presence in the best of times, but the flooding from Hurricane Irene unleashed much higher concentrations. Madden says that it’s been an education in recent weeks. He’s learned, for example, just how resilient mosquito eggs can be.

Those eggs can lay dormant for years among the leaf debris and pine needles that can be found all over the county. Along comes a hurricane like Irene, inundating many places where the eggs lay in wait, and the “flood waters reactivate them,” says Madden. “That’s why we’re having so many mosquitoes.”

Night Time Spraying To Kill The Adults, Avoid Bees

The company the County has hired, Dynamic Aviation, will be spraying a pesticide known as “Duet”. It’s an “adulticide” says Madden, and should kill the mosquitoes on contact. It is not a larvacide and won’t kill the eggs. Madden says the idea is to get the adult population down so no more can reproduce.

Kentucky and Texas took this approach after flooding and going on that experience, he says, it appears the aerial spraying “knocks down so many adults, that re-breeding is neutralized.”

The planes will fly low and release the chemical in a vapor from about 300 feet off the ground. This will happen after sunset, “mainly because,” he says, “bees are in their hives then.” It’s thought that the bees would therefore be protected. Asked about the chemical persisting on the flowers that the bees went to afterward, Madden said he thought it would not affect them.

Beekeeper Patrick Del Rio is counting on that. His hives are east of Oriental and could be sprayed. For that reason he says, “I will be covering the hives with damp sheets after sundown on the night of the spraying and will leave them covered until mid-morning at least. Once the spray settles and dries it should be minimally dangerous to foraging bees (the next day.) We’ll see.”

Del Rio, who just began selling the honey at the Oriental Farmers’ Market says he expects other beekeepers to cover their hives too. As for spraying, Del Rio writes in an email that “there is certainly a legitimate public health concern, especially for the county’s children who are susceptible to West Nile and encephalitis, and mosquito abatement is an important effort in this sort of situation where the mosquito population has exploded in late summer. I can raise more bees.”

Humans may want to limit exposure and stay inside during the spraying. According to “Duet“s Material Safety Data Sheet/Part V. Health Hazard Data “excessive inhalation of mists can cause nasal and respiratory irritation.”

Balance In A Watery County

Aerial spraying is more the exception than the rule, and Madden says he’s working to strike a balance between protecting the public from disease that could be borne by so many mosquitoes, and keeping chemicals from harming other wildlife, such as fish. Duet’s MDSD/Pat VII Environmental Protection Procedures says it conctains ‘yrethroids “which are toxic to fish and other aquatic invertebrates.”

In a county where so much land is either sometimes under water or at least at the water’s edge, it’s a tough balancing act, especialy when those mosquito concentrations are high near the upper parts of creeks where fish reproduce and hatch. That’s something state agencies want addressed before they give their blessing to the aerial spraying.

That back-and-forth has been going on in recent days. Davin Madden says the original flight plan has been “trimmed to accommodate” the wildlife and fish issues. 110,000 acres were targetted at first; it’s now down to 85,000-90,000 or approximately 140 square miles. “We pulled back from the waterways,” says Madden,

An area around a fish hatchery in the northern part of the county won’t be sprayed, either he says. Madden says that Bill Ellers at the Pamlico Cooperative Extension Service is also helping identify organic farmers who wouldn’t want their fields sprayed, as well as beekeepers, who want their hives protected. Those areas will be avoided, he says.

The county, he says, “is trying to do the best we can to minimize the impact” on things other than the mosquitoes. But there’s a limit to limiting the effects. “If we excluded every pond and lake, we might as well not spray,” says Madden. “I’m a conservationist, and I love to fish. But the last thing I want is for a child to get sick or be dying” because he, as the county’s health director, “didn’t do something” about the mosquito threat.

No Aerial Spraying in Oriental or Environs

Madden says the aerial spraying will not happen over Oriental. The Town has been spraying the chemical “BioMist” from a truck in recent weeks. It likely will not be done in the areas outside the Town’s limits either. Florence and Whortonsville will be as close to Oriental as the aerial spraying comes, he says.

Paying For It

FEMA could be paying as much as 75% of the cost of the spraying which was estimated to be more than $200,000. If the State of NC doesn’t come through with the other 25%, the Pamlico County Commission has okayed spending county money for the one-time spraying.

A count of the mosquitoes afterward will determine if any more aerial spraying is needed.

To read the Material Data Safety Sheet on Duet, click here.

——————-

Update: Tuesday, September 20 County Manager Tim Buck says that there will not be aerial spraying at all because FEMA reimbursement for 75% of the $200,000 cost was not guaranteed.

Faced with budget constraints and the prospect of having to foot most of that bill, the Pamlico County Commission voted Monday night to rescind its earlier approval of the aerial spray project. Instead, the Commissioners voted to spend $20,000 toward truck-based spraying. The funds will go toward purchase of the insecticide as well as toward the purchase of a fourth mosquito spraying truck to fleet. (Two trucks have been making the rounds while the county considered the aerial spraying.) A third truck that had not been running will be repaired as well.

The County Manager says the trucks will continue to spray on “named” streets in the areas that had been tentatively targeted for aerial spraying. Property owners, he says, may take additional measures on their land, such as keeping lawns mowed and applying insecticide.

Posted Wednesday September 14, 2011 by Melinda Penkava