West Nile Virus and Other Domestic Nationally Notifiable Arboviral Diseases — United States, 2019

Abstract

What is already known about this topic? West Nile virus (WNV) is consistently the leading cause of domestically acquired arboviral disease, but other arboviruses cause sporadic cases and outbreaks of neuroinvasive disease, resulting in substantial morbidity and mortality. What is added by this report? In 2019, WNV neuroinvasive disease incidence was 53% lower than the median annual incidence during 2009-2018. More Powassan and eastern equine encephalitis virus disease cases were reported than in any previous year. What are the implications for public health practice? Health care providers should consider arboviral infections in patients with aseptic meningitis or encephalitis, perform recommended diagnostic testing, and promptly report cases to public health authorities. Surveillance is important to identify outbreaks and guide prevention strategies, which include wearing insect repellent, long pants, and long-sleeved shirts when outdoors.