Colorado confirms first West Nile virus case of 2024 after worst US outbreak in 2023

Colorado's first confirmed cases of West Nile virus this year have raised concerns among public health officials, who say the virus doesn't typically appear in the state until late summer.

The initial case in the Arapahoe County woman indicates mosquito activity is on the rise in Colorado, which officials say could increase in the coming weeks as more storms, warmer temperatures and fewer cool nights get underway.

In 2023, Colorado experienced the worst West Nile virus outbreak in the United States and one of the deadliest years for West Nile virus since the mosquito-borne disease arrived in the United States in 1999.

Throughout 2023, West Nile virus kills 50 people in Colorado, hospitalizes dozens more.

West Nile virus can infect healthy people of any age. In severe cases, it can cause devastating neurological disorders and brain swelling. Award-winning photographer and producer Last year, he was infected with West Nile virus. Young woman endures tough recovery After the West Nile virus infection worsens in 2022.

Dr. Michelle Baron Senior Medical Director of Infection Prevention and Control at UCHealthhas two important messages for people who are currently spending time outdoors and who may be feeling unwell:

Protect yourself from mosquito bites, and if you feel unwell and think you may have West Nile virus, seek medical attention right away.

“If the infection progresses and you start experiencing symptoms like persistent headache, confusion, weakness, numbness or tingling, you should seek medical attention as soon as possible,” Baron said.

To better understand the virus and prevent people from getting sick, we asked Baron some frequently asked questions about the virus.

In addition to her work at UCHealth, Barron Professor of Medicine and Infectious Diseases in University of Colorado School of Medicine To Anschutz Medical Campus and He is one of the Rocky Mountain region's top infectious disease experts..

What is West Nile Virus?

West Nile virus is a mosquito-borne disease known as a “flavivirus” that was first detected in Uganda in 1937. The disease got its name after several major epidemics in Egypt and the Nile Delta in the 1950s.The first cases in the United States were discovered in 1999, and since then it has spread across the country. However, Coloradans have a disproportionately higher rate of West Nile virus infection than people in other more populous states.Therefore, people living in Colorado and other states where West Nile virus infection is more common should be especially careful to avoid mosquito bites.

Mosquitoes can pick up the virus from birds or other animals and transmit it to people when they bite.

Why was West Nile Virus so bad in Colorado in 2023?

The spring and summer of 2023 were wet in Colorado.

“Increased rainfall has led to increased mosquito populations this summer and they have spread more widely than usual,” Baron said.

Additionally, Coloradans love to spend time outdoors, and when mosquitoes are widespread, this, combined with many people spending time in nature, could lead to the spread of West Nile virus.

When did West Nile Virus infections begin in Colorado?

Mosquito season usually lasts from June to September, but if the fall is mild and rainy, mosquitoes may continue to be circulating and infecting people into the fall.

Is West Nile Virus a problem in other parts of the United States?

In 2023, other states saw outbreaks of West Nile virus, from California to Texas, Wyoming and the Dakotas, according to data from the U.S. Centers for Disease Control and Prevention (CDC). Colorado was shown to have experienced the worst West Nile virus outbreak in the United States in 2023.

Was 2023 one of the worst years on record for West Nile Virus in Colorado?

Colorado has had two bad years for the West Nile virus outbreak. There have been 20 deaths in 2022 and 11 deaths in 2021, according to the Colorado Department of Public Health and Environment.

Colorado's worst year on record came shortly after the West Nile virus reached the state: in 2003, 66 people died from the virus.

What are the common symptoms of West Nile Virus?

The main symptoms of West Nile virus are:

• headache
• heat
• diarrhea
• Muscle weakness
• Tingling or numbness
• Neck stiffness
• Flu-like symptoms

“Most people have mild symptoms and may not even know they have West Nile virus,” Baron said.

Do some people get a rash when infected with West Nile virus?

A rash caused by West Nile virus is not common, but it is possible. If you feel unwell and have questions about your symptoms, see your doctor.

West Nile Virus can cause severe neurological symptoms, so how do you know if you have this problem?

Neurological symptoms associated with West Nile virus include:

• Clumsiness
• Gait disturbance
• Brain fog or cognitive impairment
• Memory issues

When West Nile virus becomes severe, patients can develop serious symptoms such as encephalitis, an inflammation of the brain, and meningitis, which is swelling of the lining of the brain and spinal cord, Baron said.

“Patients sometimes start behaving oddly. They develop cognitive issues. They may have trouble finding words. They may move a little slower or develop weaknesses. They may have trouble walking,” Baron said.

“They could develop a polio-like syndrome that could prevent them from walking and leave them paralyzed,” Baron said.

Her advice to anyone experiencing these neurological symptoms is crystal clear: seek help immediately.

Is there a test for West Nile Virus?

Yes. If you are feeling unwell and suspect you may have been exposed to West Nile Virus, see your health care provider who can arrange for you to be tested for West Nile Virus.

Is there a cure for West Nile Virus?

No. Despite decades of research and efforts to find a treatment, there is still no cure for West Nile virus. In the past, doctors have experimented with using antibodies from previously infected people on newly infected patients, Baron said. Unfortunately, clinical trials showed that these treatments were ineffective.

There is no cure for West Nile virus, but doctors can help ease other symptoms, such as lowering fever and providing supportive care if there is swelling in the brain.

“If you have neurological symptoms, be sure to see your doctor because your symptoms may worsen,” Baron said.

There is no cure for the virus, but doctors can help.

“If they have difficulty breathing, we can monitor that. If they have a fever, we can control that. If they have weakness, we can work on rehabilitation,” she said.

Is there a vaccine to prevent West Nile Virus?

No. As well as treatments, researchers have been working for years to develop a human vaccine to prevent West Nile Virus. Unfortunately, there is no vaccine yet.But there is Vaccine to prevent West Nile virus in horsesSo it's possible that a human vaccine could be on the way soon.

What if I've had West Nile Virus in the past? Can I get it again? Or do I still have immunity to fight off another infection?

Although researchers and doctors are still learning about West Nile Virus, they believe that being infected with it once should provide lifelong immunity to the virus.

How can I prevent contracting West Nile Virus?

West Nile Virus is very easy to prevent, but for people who like to be outdoors, avoiding mosquitoes can be tricky.

Here are some ideas to help you stay safe.

• If you spend time outdoors, consider wearing long sleeves and long pants to reduce the risk of mosquito bites.
• Use an effective insect repellent, preferably one that contains DEET.

“Whether you're out hiking or just sitting on your deck or patio at home, it's a good idea to protect yourself by using bug spray, citronella candles, or something else that will keep mosquitoes away,” Baron says. “And make sure there aren't any standing water areas where mosquitoes can breed.”

Are there any times of the day that I should be particularly careful?

Yes, mosquitoes are most active at dawn and dusk.

“Avoiding going out during those times may help prevent West Nile virus infection,” Baron said.

Overall, her advice is to avoid getting stung: be prepared and be careful.