AUGUST 25, 2016, DOBBINS AIR RESERVE BASE, Ga. (AFNS) – Bioenvironmental engineers here recently partnered with the Georgia Department of Public Health to partake in the Defense Department initiative to combat the Zika virus and other mosquito-borne diseases.
Kathleen Schmidt, the Georgia DPH vector surveillance coordinator, along with the Dobbins Air Reserve Base engineers, laid traps at the base’s firing range due to it being an area of frequent blood-sucker complaints. Schmidt placed the traps on June 23 and collected bugs the following day for inspection.
The Georgia DPH found that 27 of the mosquitos collected were possibly the species Aedes albopictus, the Asian tiger mosquito, a species known for carrying Zika.
“Aedes albopictus does not go into traps readily, so 27 is a pretty big number,” said Dr. Rosmarie Kelly, a Georgia DPH public health entomologist. “It is definitely the mosquito of concern for this area. The numbers are high, they breed locally, they are aggressive day-time biters, and they are potential vectors for Zika. They don’t fly very far. So something close by is allowing them to breed and lay eggs.”
When more than five or six are in a trap, they are an issue, Kelly explained. Overall, the Georgia DPH has seen low numbers of the species, so that adds to this issue.
“The findings surprised us because we weren’t expecting to find this type and number of mosquitos,” said Christine Englemann, a 94th Mission Support Group bioenvironmental specialist.
After these findings, the next step for the base is to take measures to greatly reduce or eliminate the threat from the area by getting rid of their nesting opportunities, Schmidt said.
“They are aggressive feeders,” Kelly said. “But, they don’t fly very far for a blood meal. So anybody who’s there is going to run a risk of getting bitten within a couple hundred yards.”
According to the Georgia DPH, Aedes albopictus is capable of finding breeding sites where small amounts of water can be found. These sites include any container that will hold water, such as bottle caps, piles of wet leaves, black corrugated pipe, gutters, birdbaths, tires, flowerpots, and more.
The best way to control this species is to dump out or treat standing water and to cut back heavy vegetation where mosquitoes will rest when not out biting, Schmidt said.
“You need to look at anything that can hold water for five to seven days,” Kelly said. “Put holes in it to let it drain. There will always be stuff that you just can’t find. That’s where barrier spray is useful. That will last for three to four weeks. It’s really good for that particular species because they don’t fly very far.”
Zika virus spreads to people primarily through the bite of an infected mosquito but can also be spread during sex by a partner infected with Zika to their partners. Many people infected with Zika won’t have symptoms; however, Zika infection during pregnancy can cause a serious birth defect of the brain called microcephaly and other severe fetal brain defects, according to the Centers for Disease Control. Until more is known, CDC recommends that pregnant women avoid traveling to areas with Zika.
For the public, two larvicides are available for treating standing water, Mosquito Torpedoes (methoprene) and Mosquito Dunks (Bti), the Georgia DPH advises. Both are available from most hardware stores. Hand-held foggers can also be used to reduce biting populations of mosquitoes, but this solution is temporary and needs to be followed up with removing breeding sites and larviciding.
“At this point, your best bet is to police the area — get rid of breeding by potentially using barrier spray in the area to reduce the biting pressure on anyone in the area,” Kelly said.
Kelly pointed out that even with these mosquitoes around the base, Georgia has not had any locally acquired cases of Zika.
“Once the recommended corrective actions are implemented, GDPH will return for additional mosquito surveillance,” Englemann said.
At this point, Dobbins ARB has eliminated standing water; mosquito larvicide dunks were placed in ponds near the firing range; and pesticide is being sprayed to low lying bushes and trees surrounding the firing range every two weeks. Insect repellent is also available for instructors and students, and Zika information is provided to pregnant workers, Englemann said.