Local health officials have confirmed a West Nile Virus-associated death of an elderly man and two additional cases of the mosquito-borne virus in adult men in Chatham County.
These are the first confirmed human cases in the county or in the eight-county Coastal Health District this year, though Chatham County Mosquito Control has detected and reported the virus in mosquitoes since July.
Statewide, there have been a total of 31 confirmed human cases and five deaths. That makes this year the third-deadliest for the virus on record statewide.
West Nile virus was first reported in the United States in New York in 1999. It spread quickly, with Georgia reporting its first death in 2001. The next year was the state’s worst so far, with seven deaths reported. Most years have seen zero to three deaths statewide, though a spike of six occurred in 2012.
The virus occurs in a cyclical pattern here and elsewhere, said Chatham County Mosquito Control Director Jeff Heusel, though the local pattern is out of sync with the state pattern.
“Our last big year (in Chatham) was 2011,” Heusel said. “We had over 200 mosquito pools that came up positive that year. We’re at 80 some now.” Mosquito pools are samples of trapped mosquitoes that are combined and tested collectively for the virus.
It’s unclear what causes the cyclical nature of the virus’ impact, Heusel said. One theory was that it’s connected to the typical lifespan of the small- to medium-sized birds that serve as a reservoir for the disease. Heusel isn’t so sold on that theory in part because genetic testing at the University of Georgia has shown that the virus in Chatham was a different strain in 2011 than in 2007, the prior spike.
“We’re speculating that it was knocked out and we had a new strain introduced,” Heusel said. “We’re waiting to see if testing shows a new strain this year.”
In the meantime, Mosquito Control is already treating West Nile positive areas of the county with twice a week spraying.
“We’re at our highest level of response,” Heusel said.
According to the Centers for Disease Control and Prevention, about 8 in 10 of people infected with West Nile virus will show no symptoms at all; about 1 in 5 will develop a fever, headache, body aches, joint pains, vomiting, diarrhea, or rash; and about 1 in 150 will develop a severe illness affecting the central nervous system.
With no telltale symptoms and no specific cure for West Nile, avoiding mosquito bites is key, said Dr. Lawton Davis, district health director for the Coastal Health District.
“West Nile Virus is transmitted by infected mosquitoes and once we know the virus is in the mosquito population we know that, unfortunately, there is a threat to people who live in that same population of contracting the virus,” he said. “We continue to urge residents to do everything they can to keep from getting bitten by mosquitoes and to reduce mosquito breeding around their homes and neighborhoods.”
Mosquitoes that carry WNV are more likely to bite during the evening, night, and early morning. Wearing EPA-approved insect repellant containing at least 20-30 percent DEET will help keep mosquitoes away and eliminating standing water around the home and yard will help stop them from breeding.
Tip containers such as children’s toys, flowerpots, and planters after every rain or at least once a week and toss out anything that holds water, such as old tires or cans. Also clean out gutters, remove piles of leaves, and keep vegetation cut low to prevent landing sites for adult mosquitoes.
“Preventing mosquito bites and reducing breeding sites, those things you can control,” Davis said.