# Neonatal CNS Human Parechovirus Infections in Western Pennsylvania in the 2024 Season

## TL;DR

This study examines the 2024 season's neonatal infections caused by human Parechovirus A in Western Pennsylvania, focusing on their frequency, symptoms, and seasonality.

## Contribution

The study provides updated insights into the post-pandemic seasonality and clinical features of neonatal PeV-A infections.

## Key findings

- PeV-A was detected in 5.6% of febrile infants, with infections occurring from June to September.
- PeV-A positive infants showed higher temperatures, rash, and leukopenia without pleocytosis.
- None of the PeV-A infected infants developed severe disease.

## Abstract

Human Parechovirus A (PeV‐A) is a virus with near‐universal infection by age five; however, neonatal infections can lead to meningoencephalitis, sepsis, and death. Prior to the COVID‐19 pandemic, PeV‐A showed biennial seasonality with late summer peaks, but multiple viruses have had shifted circulation post‐pandemic. PeV‐A is not universally included in neonatal sepsis testing; thus, the frequency and clinical spectrum of PeV‐A neonatal meningoencephalitis are not fully described. We sought to evaluate the epidemiology, seasonality, and clinical presentation of neonatal PeV‐A in the 2024 season. We collected remnant cerebrospinal fluid samples from febrile infants under 60 days at a single children's hospital in Southwestern Pennsylvania and assessed for PeV‐A and enterovirus (EV). Six out of 107 (5.6%) febrile infants were positive for PeV‐A and 24 (22.4%) were positive for EV. PeV‐A infections occurred from June to September. PeV‐A positive patients had a distinct combination of higher maximum temperature, rash, and leukopenia without pleocytosis. None of these infants had severe disease. Systematic surveillance of PeV‐A is required to completely understand ongoing PeV‐A circulation patterns, expected clinical course, and long‐term developmental implications.