Threat of West Nile virus spikes as host mosquitos are 10x more abundant than last year in Northern Colorado

The threat of West Nile virus infections among humans is rising as health departments across Northern Colorado have seen a dramatic spike in the number of host mosquitos that carry the virus. 

The Culex mosquitos are the ones that carry and transfer the potentially deadly virus to humans, and Larimer County alone has seen the number of those mosquitos explode in recent weeks. 

According to the Larimer County Health Department, the number of Culex mosquitos being trapped for study in the county is more than 10 times higher than at the same time in 2022.  

Both Larimer and Weld counties have detected the virus in mosquitos this year. However, Larimer County has not yet had a confirmed human case. Though, it is very likely someone has already received the illness and isn't aware. 

80% of people who get West Nile virus never know due to insignificant or unnoticeable symptoms. However, one in every 150 people who contract the virus end up experiencing severe illness, according to Kori Wilford of the Larimer County Health Department.  

"The abundance of mosquitos right now is concerning," Wilford said. "We currently have no reported cases in humans of West Nile virus. But, when the mosquitos that carry the virus become abundant, typically it is just a matter of time before we start seeing those human cases." 

Some outdoor enthusiasts decided to go outside for camping, swimming or tubing opportunities during the holiday weekend.  

"I am going tubing with my family. They told me it would be fun," said Jordan Ma, a visitor to the Poudre River.  

Ma said she was looking forward to tubing the river, a popular activity during summer months in Northern Colorado. However, she said she didn't know there was a heightened risk of mosquitos and West Nile.  

"Nobody told me about the mosquitos and the viruses," Ma said. "I should have worn pants today." 

Some told CBS News Colorado that they noticed in recent weeks an influx of mosquitos and mosquito bites in the evenings. However, they said they wouldn't let that stop them from still enjoying the outdoors.  

To avoid contracting the virus, or from getting mosquito bites, people are encouraged to wear mosquito repellant. You can also wear long sleeves and pants, and avoid outdoor activities at dusk and dawn.  

Also, to cut down on the amount of mosquitos around your property, it is encouraged that you rid of any still standing water outdoors where mosquitos tend to thrive.