What is West Nile Virus & Should I Be Worried?

October 5, 2021

Clinical Contributors to this Story

Cristina Cicogna, M.D. contributes to topics such as Infectious Disease.

By: Katie Woehnker 

After a summer of spotted lantern fly invasions and murder hornets, mosquitoes are back for a piece of the action.

As reports of West Nile virus (WNV) are on the rise, our infectious disease specialist, Cristina Cicogna, M.D., shares bite-sized information about the mosquito transmitted virus.

What is West Nile virus?

“West Nile Virus is the most common cause of infectious disease spread by mosquitoes to humans in the U.S.,” Dr. Cicogna shares. “While found in over 300 species of birds, this virus can also infect other animals like dogs, cats, horses, squirrels and other mammals.”

Which mosquitoes carry West Nile virus?

The mosquito species, Culex pipiens, are identified as the primary spreader of West Nile virus. These buggers are often referred to as the common house mosquito or the northern house mosquito, and are found in urban and suburban areas.

Why do mosquitoes carry disease?

Mosquitoes can carry an array of diseases, like Zika virus or malaria, and their thirst for blood is essential for disease transmission.

“There is a transfer of fluids between you and the mosquito at the time of the bite,” shares Dr. Cicogna. “When an infected mosquito bites you, they draw in your blood, and leave their saliva behind, directly inoculating the virus in your bloodstream.”

“Not all mosquitoes carry diseases, most species just cause a pesky annoyance,” Dr. Cicogna adds.

What are symptoms of West Nile virus?

Most people will not develop symptoms from West Nile virus.

According to the CDC, about one in five will develop a fever along with the following symptoms:

  • Headache
  • Body ache
  • Rash
  • Joint pain
  • Diarrhea
  • Vomiting
  • Fatigue
  • Weakness

In about one in 150 cases the virus will infect the brain or the nerve cells resulting in a more serious illness, resulting in symptoms of severe headache, disorientation, coma, tremors or paralysis.

There is no vaccine to prevent West Nile virus or specific medicines for treatment. Over-the-counter pain relievers can help to bring down your fever and alleviate some discomfort.

How long after a mosquito bite do you get West Nile?

Signs and symptoms of West Nile virus usually appear within four to ten days after being bitten.

What are mosquitoes attracted to?

“There are many contributing factors to why a mosquito may choose you to bite – the way you’re dressed, your scent, what you eat or even your genetic makeup,” Dr. Cicogna adds.

Mosquitoes are attracted to:

  • Stagnant water
  • Dark, bold colors like black or navy blue
  • Floral perfumes found in deodorants, lotions and bath products
  • Strong body odor
  • Alcohol consumption
  • Blood type O
  • Carbon dioxide (working out may draw them to you as you exhale more frequently)
  • Pregnant women

How do I stop getting bitten by mosquitos?

“The best way to protect yourself from mosquitoes is to take the proper safety precautions while hanging outside,” advises Dr. Cicogna.

  • Wear clothing that covers your arms, legs and feet
  • Wear loosely fit clothing, mosquitoes will bite through tight clothes
  • Use insect repellent
  • Use screens and netting to protect your indoor spaces
  • Remove any areas of standing water where mosquitoes like to breed. For standing water that cannot be removed and will not be used for drinking, consider treatment with a product that kills the mosquito larvae. Be sure to always follow the product label instructions.

“Mosquitos are most active in the warmer weather, so most bites and infections will happen during the summer and warmer months. However, don’t let the fall season fool you, it’s still fairly warm and it may be a few more weeks before they enter hibernation.”

Next Steps & Resources:

The material provided through HealthU is intended to be used as general information only and should not replace the advice of your physician. Always consult your physician for individual care.