What is the mortality and morbidity associated with West Nile virus infection?

Updated: Apr 02, 2018
  • Author: Jess D Salinas, Jr, MD; Chief Editor: Elizabeth A Moberg-Wolff, MD  more...
  • Print

Reports indicate that less than 1% of persons who are infected with the West Nile virus develop severe illness; of individuals who have severe illness secondary to the infection, 3-15% die.

Severe disease particularly affects the elderly. Advanced age is by far the greatest risk factor for neurologic disease, long-term morbidity, and death, especially in persons older than 75 years. Of the 119 patients who died of West Nile virus in the United States in 2013 (out of 2469 cases), the median age was 78 years. [13, 14]

The total number of reported deaths from the West Nile virus in the United States between 1999 and 2016 was 2017 (4% of cases), including 1888 from neuroinvasive disease. [18]

Did this answer your question?
Additional feedback? (Optional)
Thank you for your feedback!