Combating West Nile Virus Disease — Time to Revisit Vaccination
Carolyn V. Gould, J. Erin Staples, Claire Y.‐H. Huang, Aaron C. Brault, Randall J. Nett
Abstract
It is time to revisit the need for human West Nile virus (WNV) vaccines.Since its initial detection in the United States in 1999, WNV has become the leading cause of domestic arthropod-borne viral (arboviral) disease.Spread by infected culex-species mosquitoes, WNV has caused more than 55,000 reported cases of human disease, more than 27,000 of them neuroinvasive, and 2600 deaths between 1999 and 2021, according to data from the Centers for Disease Control and Prevention (CDC).WNV is also an ongoing public health threat in many areas of the world; the largest recorded outbreak in Europe occurred in 2018.Despite development and expansion of WNV-specific mosquito surveillance and control programs over the past two decades, a consistently high burden of disease is reported each year in the United States. 1 At a subnational level, the occurrence of WNV is both geographically focal and sporadic, making it difficult to predict outbreaks and leading to regional and temporal variation in disease burden; for example, in Maricopa County, Arizona, more than 1400 WNV disease cases and 100 resulting deaths were reported in 2021, as compared with only 3 cases the previous year.In addition to morbidity and mortality, WNV disease results in substantial costs to patients and society.Between 2004 and 2017, a total of 3109 California residents were hospitalized with WNV, with estimated hospital costs averaging $59.9 million per year. 2 Primary prevention of WNV and other domestic arboviral diseases currently includes personal protective measures to reduce vector exposure and community-based mosquito control programs.But these approaches have limitations.Adherence to personal protective measures, such as wearing long sleeves and long pants, avoiding outdoor activities during periods of high vector activity, and using insect repellent, is often low.Intensive, reactive vector-management programs have been effective in reducing the size of WNV outbreaks but are costly and typically initiated only after many cases have already occurred. 1Proactive strategies, such as larvicide application and intensive, early-season adult mosquito control,The findings and conclusions in this article are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.