Heat, resurgence of ravens, magpies raise the risk of West Nile outbreak
For as much as summer lovers dig the long, warm days, the buzz-killers of summer — mosquitoes — thrive on the heat even more.
Aside from their annoying nature, culex mosquitoes can be more harmful to people than the itchy welts they leave after extracting a blood meal.
In 2004, West Nile virus was most prominent locally, racking up 127 reported cases in Mesa County and killing four people.
The virus is spread by mosquitoes after they contract the disease mainly from birds in the corvid family, which includes crows, ravens and magpies.
In the years since, West Nile virus in residents has tapered off, with no cases reported in Mesa County in 2008. One person died from the virus in 2009, when only two cases were reported.
One confirmed case of West Nile virus in a Weld County resident has been reported this year, the Colorado Department of Public Health and Environment said in a news release Friday.
Much of the local corvid bird population was wiped out by the virus in 2004, but reports this year are that those birds are coming back.
That is causing local health professionals to wonder whether West Nile virus will reappear in force this summer, Mesa County Health Department spokeswoman Kristy Emerson said.
A recent bout of consistently warm weather has caused the mosquitoes to hatch in large numbers, Emerson said.
“Culex mosquitoes like the hot temperatures,” she said. “Usually we see more in July, August and September.”
No culex mosquitoes with West Nile virus have been reported in Grand Junction this year, according to samplings. Only the female culex mosquitoes transfer West Nile virus to a host.
Although anyone can be susceptible to contracting the disease, the risk can be reduced by taking precautions against getting mosquito bites.
The Health Department encourages residents to drain standing water on their property, use bug spray and wear long-sleeve clothing when necessary.
City workers place larvicide into some storm drains and other areas to kill mosquito larvae before they hatch.
Severe cases of West Nile virus can lead to encephalitis or meningitis, which is inflammation of the spinal cord or brain.
People infected by West Nile can display a range of symptoms, including fatigue and paralysis.
Mosquitoes also can transmit Saint Louis encephalitis, a rare but severe neuroinvasive disease that can cause death in older people.
Most people who get infected with West Nile virus don’t display any symptoms. That may be one reason the virus appeared to run its course after sweeping the nation from east to west, starting in 2002, and touching down most prominently here in 2004.
Once a person is exposed to the virus, it cannot be contracted again, Emerson said.