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

Picornaviruses including Enterovirus species A-D (EV) and Parechovirus 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) during 2007 through 2016. The overall prevalence for EV was 16% (862/5362) and 7% (271/4016) for PeV. Among all picornavirus CSF detections EV was 76% and PeV-A was 24%. Multiple EV types co-circulated each year with a total of 31 EV types detected in the 10-year period; majority belonged to EV-B species (96%). Two PeV-A types were detected; PeV-A3 was the dominant PeV-A type (95%). Top five picornaviruses (PeV-A3, 26%; E30, 11%; E6 10%; E18 9%, E9 7%) in the CSF of infants accounted for two-third 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.