Disease-carrying mosquitoes spotted in area counties
CHAMPAIGN — Asian tiger mosquitoes, which can carry the chikungunya virus, are turning up in Champaign County for a fourth summer in a row and have also been found in Vermilion County, public health officials said.
These mosquitoes that bite mostly during the daytime haven’t spread the disease in Illinois so far, officials said.
But the Champaign-Urbana Public Health District has taken steps to warn travelers going to and arriving from more heavily infected areas of the world about the risks and to prepare for potential chikungunya cases in the area.
That includes posting warning signs at Willard Airport and alerting local medical providers about chikungunya symptoms, which most commonly include fever and joint pain.
Just four of this year’s 484 U.S. cases of chikungunya (chik-en-GUN-ye) have been acquired locally, all of them in Florida.
Others have been linked to travel outside the country, mostly in the Caribbean and South America, with a small number connected to travel to the Pacific Islands and Asia, according to the Centers for Disease Control and Prevention.
There have been four cases of chikungunya in Illinois to date this year, all associated with overseas travel, Illinois Department of Public Health spokeswoman Melaney Arnold said. There were five Illinois cases last year, also associated with travel.
There’s no medication to treat the illness, and deaths from it are rare, health officials said.
Asian tiger mosquitoes first began turning up in Champaign County in 2011, said Jeff Blackford, program coordinator at the public health district.
“The first year we only found a few,” he said.
Their numbers have grown over the last couple of years, though this summer only about 50 have been found in monitoring traps, he said.
The Vermilion County Health Department has also found Asian tiger mosquitoes this summer but doesn’t keep track of their numbers, according to Environmental Health Director Doug Toole.
The Asian tiger mosquito count may be down in the area this summer because it breeds much like Culex mosquitoes do, Blackford said. Culex mosquitoes, which can carry West Nile virus, like hot, dry weather and tend to breed in sources of standing water.
“Everything we tell people about West Nile is important about reducing (Asian tiger mosquitoes) too,” Blackford said.
One big difference between the two mosquitoes, he said, is the Culex feeds from dusk to dawn, and the Asian tiger mosquito is out looking for meals mostly during the daytime.
The public health district wanted to prepare for potential chikungunya infection because Asian tiger mosquitoes can carry several viruses, among them dengue fever, and these mosquitoes are in the area, Blackford said.
A traveler returning from another part of the world with chikungunya, for example, could be bitten by an Asian tiger mosquito while still infectious, and the mosquito could then bite other people and spread the virus.
Because Asian tiger mosquitoes found in public health traps aren’t tested for this virus, the first sign of chikungunya in the area would be someone becoming sick, Blackford said.
The University of Illinois’ McKinley Health Center is also prepared for any infections turning up on campus by making sure its clinicians recognize the signs, its director Dr. Robert Palinkas said.
Doctors can’t offer vaccine protection for Dengue or chikungunya, he said.
“The only protection we can offer before they travel, as physicians, is give them really good advice about avoiding mosquitoes,” Palinkas added.
Some clues that might point to whether the mosquito that bit you is an Asian tiger, besides the time of day, are that they’re known to be aggressive biters and they have white banded legs with a white stripe on their heads.
“They’re kind of mean-looking,” Blackford said.
And they may be around to stay.
“They’re very invasive, and once they get into areas of the country they tend to stay,” Blackford said.
In terms of mosquito virus threats, he contended West Nile virus is still the bigger threat to be concerned about. West Nile hasn’t turned up in Champaign County yet this summer, but Blackford said that could change with a shift in the weather.
5 things to know about chikungunya
1. Most people infected will develop some symptoms.
2. It takes three to seven days for symptoms of fever and joint pain (sometimes also headache, rash, muscle pain and joint swelling) to turn up after the bite of an infected mosquito.
3. The symptoms are similar to those of dengue, also spread by mosquitoes.
4. Most people feel better in a week, but joint pain can persist for months.
5. Someone once infected is likely to be protected from future infections.