WELD COUNTY, Colo. – The first death from West Nile virus in Colorado for the 2023 season has been reported in a 53-year-old man from Weld County who died after complications from the disease.
So far this season, 12 human cases of West Nile virus have been confirmed in residents of eight counties across the state, according to the Colorado Department of Public Health and Environment (CDPHE). West Nile virus has also been found in eight of the 11 counties that have tested mosquitoes this season, including Adams, Arapahoe, Boulder, Delta, Denver, Larimer, Pueblo, and Weld counties.
In a statement, state health officials said the number of cases is more than Coloradans would typically see at this time of year.
“The number of West Nile virus-infected mosquitoes we've detected this season is the highest we've seen in years,” said CDPHE’s state epidemiologist Dr. Rachel Herlihy. “This is especially concerning now that August is here and September is just around the corner, as this is usually when human cases peak in Colorado.”
West Nile virus is endemic in Colorado, meaning anyone can get infected with the virus if they encounter mosquitoes in areas where they live and breed.
Symptoms of West Nile virus infection appear two to 14 days after exposure, with 1 in 5 people developing fever, body aches, headache, vomiting, diarrhea, joint pain, weakness and occasionally skin rashes and swollen nymph nodes.
While most people infected with West Nile virus don’t have symptoms, around 1% of those infected can develop a serious, sometimes fatal, neuroinvasive disease, for which there is no cure. There are also no medications to treat, or vaccines to prevent, a West Nile virus infection.
People older than 60 years old or those with certain medical conditions such as being immunocompromised, diabetic, fighting cancer or those with kidney disease are most at risk of developing neuroinvasive disease, according to Dr. Daniel Pastula, an infectious disease specialist at UCHealth and chief of neuro-infectious diseases and global neurology at the University of Colorado School of Medicine and Colorado School of Public Health.
How to protect yourself and your family from West Nile virus
Health experts have been warning Coloradans to protect themselves as populations of Culex mosquitoes were expected to increase this year due the unusual amount of precipitation this winter and spring.
As mosquito season continues, health officials recommend taking the following steps to protect yourself and your family from West Nile virus:
- Limiting activities outdoors at dusk and dawn, when mosquitoes are most active
- Wearing long pants, long-sleeved shirts, and socks in areas where mosquitoes are active
- Using an insect repellent containing DEET, picaridin, oil of lemon eucalyptus, or para-menthane-diol
- Eliminate sources of standing water near your home, which can become a breeding ground for the mosquitoes that carry West Nile virus.
In addition to eliminating sources of standing water around your home weekly, you can also mosquito-proof your home by installing or repairing screens on windows and doors.
The CDPHE recommends talking with a health care provider if you develop a fever with severe headaches or confusion following a mosquito bite.
Last year, Colorado reported 206 human cases of West Nile virus, including 20 deaths.