West Nile Virus Stats and Facts

FACTS

1. West Nile virus (WNV) can cause a fatal neurological disease in humans.
2. Approximately 80% of people who are infected will not show any symptoms.
3. West Nile virus is mainly transmitted to people through the bites of infected mosquitoes.
4. The virus can cause severe disease and death in horses.
5. Vaccines are available for use in horses but not yet available for people.
6. Birds are the natural hosts of West Nile virus.
7. WNV can cause neurological disease and death in people. WNV is commonly found in Africa, Europe, the Middle East, North America and West Asia.

STATS

• Infection with WNV is either asymptomatic (no symptoms) in around 80% of infected people, or can lead to West Nile fever or severe West Nile disease.
• About 20% of people who become infected with WNV will develop West Nile fever.
• As of July 23rd, 34 states have reported West Nile virus infections in people, birds, or mosquitoes in 2019.
• In 2018, 49 out of 50 states and the District of Columbia reported West Nile virus infections in people, birds, or mosquitoes. Overall, 2,647 cases of WNV were reported in humans, and there were 167 (6.3%) confirmed deaths in 2018. This data shows an increase from the number of human cases reported in 2017 (2,097). It also brings attention to the increase in lives lost, when compared to the 146 (7%) confirmed deaths in 2017 and the 106 (4.9%) confirmed deaths from WNV in 2016.
• The majority (4 out of 5) of people infected with West Nile virus will experience no symptoms.
• Approximately 20% of people affected by the virus will experience flu-like symptoms including fever, headache, nausea, muscle pain, and swollen lymph glands.
• Other symptoms may include a stiff neck, rash, sleepiness or disorientation.
• Less than 1% of those infected will develop West Nile Encephalitis or Meningitis, which can lead to coma, tremors, convulsions, paralysis, and even death.