Mosquitoes carrying West Nile virus identified in Sedgwick County

Sedgwick County is at high risk for West Nile virus, according to the Kansas Department of Health and Environment.

The report for the week ending on July 20 showed high risk for south-central, north-central, northwest and southwest Kansas.

Northeast and southeast Kansas are at moderate risk.

According to the report, Sedgwick County is at high risk because of an increased average temperature over a two-week period and an increase in the mosquito species known to carry the virus, compared to 2017.

Chris Steward, health protection director at Sedgwick County, said there have not been any West Nile cases in the state yet.

“August and September is usually the time we see the most cases,” Steward said. “We know in this area that West Nile is present every summer. We monitor mosquitoes to sound the alert so that precautions can be put in place.”

The Sedgwick County Health Department works with the Kansas Department of Health and Environment, the Kansas Biological Survey, the Kansas Health and Environmental Laboratories and the City of Wichita to monitor mosquito levels in Sedgwick County.

Sedgwick County’s mosquito surveillance began on May 13 and will continue through mid-October.

Mosquitoes are collected from traps and then identified by species, which indicate if they carry viruses. The Culex species is known to carry the West Nile virus.

The number of mosquito traps set in Sedgwick County decreased from nine in 2017 to five in 2018 due to funding state cuts. But the state’s mosquito surveillance now includes Reno and Shawnee counties.

This year, volunteers from Sedgwick County Extension Master Gardeners Program are doing the trapping and surveillance instead of the state, Steward said.

According to the Kansas Department of Health and Environment’s website, West Nile virus is the most common mosquito-borne disease in Kansas and the United States.

The time of year, number and location of infected mosquitoes and the number of days with sufficient heat determine the risk of being infected with the West Nile virus.

Warm temperatures increase the rate of mosquito larvae development, increasing the mosquito population, according to the Kansas Department of Health and Environment.

The virus can be spread from a mosquito to a person but cannot be spread person to person. There are no vaccines to prevent West Nile virus or medications to treat it.

Steward said about 80 percent of the people who get West Nile do not show symptoms and about 20 percent show flu-like symptoms. Less than one percent show severe symptoms, which include high fever, paralysis or death.

“We don’t want people to be in that less than one percent and be hospitalized,” Steward said.

About 1 in 5 people who are infected develop a fever and other symptoms such as headache, body aches, joint pains, vomiting, diarrhea or rash. Around 1 out of 150 infected people develop a serious illness affecting the central nervous system such as encephalitis, inflammation of the brain, or meningitis, inflammation of the membranes that surround the brain and spinal cord.

Symptoms of severe illness include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis, according to the Centers for Disease Control and Prevention.

“If people are experiencing symptoms, call the doctor and let them know they have had mosquito bites and if they’re very sick, experiencing high fever, maybe even paralysis, get medical attention immediately,” she said.

The risk of West Nile virus usually peaks during July, August and September.

Steward said to help prevent bites, people should eliminate standing water.

“It only takes a tiny bit for a mosquito to lay eggs,” Steward said. “If people have ponds or bird baths, they can put something called ‘dunks’ that you can get at hardware stores and they don’t cost very much. Depending on the amount of water, you can throw the whole thing in there and it decreases the number of mosquito larvae, so that helps decrease the mosquito population, and they are also safe for fish and other animals.”

In 2017, the Centers for Disease Control and Prevention reported Kansas had 25 confirmed and probable cases of West Nile virus.People who have had the virus before are said to be immune.

The Sedgwick County Health Department recommends people follow the “Three D’s” of mosquito-bite prevention: Drain, DEET and Dress, as well as other preventative steps:

▪ Drain any areas with standing water, which mosquitoes use to breed. The health department recommends changing bird baths, pet dishes and wading pools several times per week.

▪ Use insect repellents that contain DEET, which offers the best protection against mosquito bites.

▪ Dress in long, loose-fitting clothing when outdoors, especially at dawn and dusk.

▪ Keep screens on windows and doors in good repair

▪ Use air conditioning if you have it

▪ Use mosquito netting on baby carriages and playpens

▪ People older than 50 or those who are immunocompromised may consider adjusting outdoor to avoid peak mosquito hours. Dawn and dusk is when Culex mosquitoes are out, Steward said.

This story was originally published July 24, 2018 at 4:06 PM.