Emergence of Parechovirus A3 as the Leading Cause of Central Nervous System Infection, Surpassing Any Single Enterovirus Type, in Children in Kansas City, Missouri, USA, from 2007 to 2016.

Picornaviruses, including species A to D (EV) and species A (PeV-A), are the leading reported causes of pediatric central nervous system infections in the United States. We investigated the molecular epidemiology of EV and PeV-A over 10 years in cerebrospinal fluid (CSF) collected from children seen at Children's Mercy-Kansas City (CMKC) from 2007 through 2016. The overall prevalence for EV was 16% (862/5,362) and 7% (271/4,016) for PeV. Among all picornavirus CSF detections, EV was 76%, and PeV-A was 24%. Multiple EV types cocirculated each year, with a total of 31 EV types detected in the 10-year period; the majority belonged to EV-B species (96%). Two PeV-A types were detected; PeV-A3 was the dominant PeV-A type (95%). The top five picornaviruses (PeV-A3, 26%; E30, 11%; E6, 10%; E18, 9%; E9, 7%) in the CSF of infants accounted for two-thirds of all detections, and PeV-A3 was the leading picornavirus detected. Routine testing and reporting of PeV-A in addition to EV, especially in children under 6 months old with acute febrile illnesses, could reduce hospital stays and antibiotic usage.