The number of West Nile virus cases in Colorado surges when they reach their highest levels in five years.health

Both West Nile virus infections and deaths have increased since last year, with more cases since 2016 than at any time so far. According to data from the Colorado Department of Public Health and Environment.

As of this week, 139 Coloradons had mosquito-borne illnesses and 6 died. These numbers are up 297% and 500%, respectively, compared to 2020. In fact, according to the State Department of Health, this year’s reported cases are the third highest since 2010.

According to CDPHE data, COVID-19 claims to have killed 2,574 people in Colorado from the beginning of this year to October 7, but during the relatively mild flu season of 2020-21. Took more time. 6 lives, West Nile fever numbers indicate that there is another potentially deadly virus out there, and experts say that precautions need to be taken.

However, despite the surge in West Nile fever cases and deaths, many health officials say it is not unusual for numbers to vary from year to year, and precautions reduce the likelihood of contraction. I emphasized that I can.

Daniel Pastura, an associate professor of neurology, medicine and epidemiology at the University of Colorado School of Medicine and the University of Colorado School of Public Health, said: “There have been no cases in some years, and there are so many cases in some years.”

The virus was first discovered in women in the West Nile district of Uganda in 1937, and was subsequently identified in birds in the Nile Delta region in 1953. World Health Organization..

Mosquito-borne illnesses are known to cause fever and headaches and, in severe cases, can cause nerve-infiltrating illnesses and death. Still, 80% of people infected with the virus show no symptoms, Pastura said.

Approximately 1 in 150 infected mosquito bites develop neuroinvasive diseases such as encephalitis, cerebral infections, and meningitis. According to the US Centers for Disease Control and Prevention, about 10% of severely infected people die of illness, and survivors may have long-term nervous system problems.

However, this year, 79 (57%) of Colorado cases were classified as nerve infiltration cases, the highest number since 2013. The greatest risk of severe cases is in people over the age of 60 or with immunosuppressive disease. CDPHE.

For decades, the virus remained in the Eastern Hemisphere, but in 1999 it began to cross the Atlantic Ocean and invade the Americas.

The first reported cases in Colorado were confirmed in 2002, and by the following year the number of cases had reached “epidemic levels” and 2,948 cases had been confirmed, said Jennifer House, a state public health veterinarian.

“2003 had a year called the epidemic. Almost all of Colorado was free of the virus, so there was no immunity to birds, horses, or people,” House said. .. “Since then, it has existed in the state and has been seen by people every year since its outbreak in 2003.”

Mosquitoes infect potentially deadly viruses through birds and spread the disease to people, horses, and rarely pets. Medical experts know how insects can infect and spread the disease, but House said it is impossible to eradicate.

“We can’t get rid of it because it’s transmitted by birds and they move, so there’s no way to get rid of the virus,” says House.

Although the virus cannot be eradicated, health officials have devised several ways to reduce the likelihood of infection, including mosquito capture, testing, and outreach education, officials say.

For example, Larimer County, which reported 17% of all cases reported in Colorado between 2003 and 2020, collected more than 100 mosquito traps throughout the county.

Larimer is one of the five “hotspot” counties with the highest risk of infection. According to state data, the Boulder, Delta, Mesa, and Weld counties are others, and since 2003, this group has accounted for 53% of all cases in the state.

A spokeswoman for the Larimer County Health Department, Kori Wilford, said every June, Larimer County authorities would implement surveillance measures to monitor mosquito traps and analyze captured insects.

“They will see mosquitoes, see Culex pipiens, the mosquito that infects the West Nile virus, and then test them and start looking for infection,” Wilford said.

Other methods used in Larimer County vary by municipality. Labrand regularly sprays in the air, but Fort Collins does not spray until the number of mosquitoes reaches a certain threshold.

Aerial spraying, a popular mosquito control method, “helps minimize the problem of mosquito discomfort and stop the spread of mosquito-borne diseases such as West Nile fever,” Wilford said. increase.

Other communities, such as Broomfield County, have contracted with mosquito control agencies to implement mitigation measures such as aerial spraying.

Spraying, testing and analysis reduce the number of infected mosquitoes, but not 100% eradication. Health officials also issued public service announcements on the virus, “Fordies”:

• Drainage: Mosquitoes breed in water. Drain the water in the garden every week. Bird baths, gutter clogging, and children’s pools are common breeding grounds.
• Dress: Wear lightweight long-sleeved shirts and long trousers outdoors. As mosquitoes bite your clothes, spray them with an insect repellent.
• Protection: Apply a modest amount of insect repellent to exposed skin. Use repellents approved according to the label. During peak season, infected mosquitoes can be found throughout the front range, so use repellents wherever you live, work, or recreate.
• Dawn / Dusk: The best way to avoid the West Nile virus is to avoid mosquito bites. If possible, stay indoors during peak mosquito hours. From sunset to 1.5 hours after sunset appears to be the most active “feeding time” for West Nile virus-carrying species.

These rules must be followed from June to the first frost of the year, Haus said.

Haus said he expects the number of cases to continue to grow until the first frost.

Authorities know how the virus spreads and some factors that contribute to the “bad year,” but House says it’s nearly impossible to predict how each season will occur. rice field.

“It involves a number of factors, including climate, early spring rainfall, stagnant water, and the subsequent hot and dry summers, so it’s actually very complicated,” says Haus.

Eighty percent of people infected with the virus are asymptomatic, but Pastura said people should still take the potentially deadly virus seriously.

“You can’t get West Nile fever without being bitten by a mosquito,” Pastura said. “Wear insect repellent, avoid activities in places where mosquitoes are likely to occur at dusk or dawn, consider wearing long pants and sleeves, consider wearing permethrin on clothing, and mosquitoes are active. Sometimes stay indoors. “