Postnatal Care–associated Echovirus 11 Infection in Malaysia: Severe Disease With Variable Outcomes

BACKGROUND: Echovirus 11 (E11) is a common circulating enterovirus globally and in Malaysia. In recent years, severe neonatal E11 infections have been increasingly reported in Europe and Asia. An increase in severe E11 cases reported in Malaysia highlights significant potential for transmission in postnatal environments in hospitals and the community. METHODS: We present clinical and laboratory findings for 5 neonates admitted with laboratory-confirmed E11 infection in Kuala Lumpur, Malaysia, between September 2023 and January 2024. E11 was diagnosed by virus culture or polymerase chain reaction. The E11 VP1 genes were sequenced and compared to other global E11 sequences. RESULTS: Patients were between 2 and 9 days of age. Four cases presented with multiorgan failure with prominent liver dysfunction requiring intensive care, and 2 died. Two had the unusual complication of thrombotic microangiopathy. The fifth patient had uncomplicated meningitis. All cases had E11 viruses of D5 genotype, similar to recently reported global sequences. Two patients with identical virus sequences had been in the same neonatal unit of another hospital, implying a common source. The other 3 were community-acquired cases with related viral sequences. Three cases were admitted from different confinement centers, which are postnatal community care facilities for newborns and mothers. CONCLUSIONS: E11 genotype D5 is the main cause of the recent global upsurge of severe neonatal E11 infections. Severe multiorgan disease and hemorrhagic hepatitis syndrome are associated with poor prognosis. E11 transmission in postnatal settings shows the importance of stringent infection control practices, especially in community confinement centers, which are becoming increasingly widespread.