Two birds have tested positive for West Nile virus in Cole County this summer, according to the Missouri Department of Health and Senior Services.
A crow was found June 2, and a great horned owl was found Aug. 28, DHSS online records show.
The owl, which was found in Jefferson City limits, was taken to a veterinarian's office, where it died, Cole County Health Department Director Kristi Campbell said.
The location where the crow was found was not reported.
West Nile virus can infect a variety of bird species and is transmitted by the bite of infected mosquitoes, according to the Centers for Disease Control and Prevention. Also transmitted to humans via mosquito bites, most people infected with West Nile virus do not develop symptoms, while some may develop flu-like symptoms such as fever and body aches and a few may experience serious symptoms such as illnesses affecting the central nervous system.
The CDC has taken reports of 326 cases of West Nile virus in people in 2019, as of Sept. 4. West Nile virus infections in people, birds or mosquitoes have been reported in 45 states and the District of Columbia this year, according to the CDC.
So far this year, 26 reports of dead birds have been recorded from various parts of Missouri involving species known to be sensitive to West Nile virus infection, DHSS reported.
DHSS does not test dead birds for West Nile virus but does receive reports of infected birds from other state and federal agencies, agency Communications Director Lisa Cox said. Members of the public can report dead birds to DHSS to aid in West Nile virus activity tracking via an online form.
The two birds in Cole County were brought to private veterinary facilities, which tested them, Campbell said.
The danger of catching a mosquito-borne illness continues into late summer, DHSS officials cautioned in a recent news release. As long as temperatures remain warm, mosquitoes will continue to be a pest and a potential health danger.
While increased mosquito activity created by flooding this spring can lead to mosquitoes that are aggressive biters, these do not pose a higher West Nile virus risk, DHSS Director Dr. Randall Williams said in the news release.
Pools of stagnant water left by receding floodwaters and summer rain create the perfect breeding grounds for mosquitoes that can carry the virus, however.
Jefferson City Environmental Health Manager David Grellner recently told the News Tribune that while the city has not received any health concerns regarding the standing water in North Jefferson City, since July city staff have been treating and monitoring stagnant water in that area for mosquito breeding habitat. That includes spraying for mosquitoes periodically, which they plan to continue until cold weather season.
Over the past five years, around 20 West Nile virus disease cases have been reported annually in Missouri, including an average of almost two West Nile virus-associated fatalities each year. The highest number of recorded West Nile virus cases in Missouri in a single year was 168 in 2002, with eight associated deaths.
To date in 2019, DHSS has recorded one human case of West Nile virus in Missouri. This case was the "neuroinvasive" form of the disease, which means it can involve the brain and other parts of the nervous system and might result in permanent neurologic damage or death, according to the department's news release. This case did not result in a fatality.