Echovirus 11 outbreak among neonates in Selangor, Malaysia: An epidemiological investigation

Abstract

Introduction

Community outbreaks involving enteroviruses, particularly Echovirus 11 pose a significant threat to neonates. We aim to present descriptive findings from an epidemiological investigation of a disease outbreak among neonates in two confinement centres located in an urban district of Selangor state, Malaysia, between November and December 2023.

Material and Methods

We conducted a walk-through survey, environmental inspection and laboratory investigations in two confinement centres designated as A and B. Rectal swabs were collected to detect the presence of enteroviruses with further viral sequencing.

Results

In total, ten neonates in the two confinement centres were infected with Echovirus 11, resulting in a total attack rate of 40.0% among the 17 neonates and 8 adult staff members. All infected neonates were of Chinese ethnicity. No epidemiological link was found between cases in confinement centre A and those in centre B. None of the adult close contacts tested positive for Echovirus 11. Sixty percent of the infected neonates presented with fever, while approximately 33.3% exhibited symptoms of meningoencephalitis. All cases required hospitalization, with the exception of one fatality, resulting in a mortality rate of 10.0%. Although disposable diapers were used for all neonates, they were not disposed of immediately after being changed. Disinfection of the bathing basin consisted solely of using Dettol antiseptic liquid.

Discussion

The likely source of this Echovirus 11 outbreak was community-acquired, with the fecal-oral route identified as the most probable mode of transmission. Echovirus 11 infection, when not manifested as hand-foot-and-mouth-disease, is not a notifiable disease in Malaysia. Regular disinfection with Dettol (which contains the key active ingredient Chloroxylenol) was deemed inadequate. Therefore, emphasizing the importance of thorough handwashing with soap and water, implementing measures such as prohibiting new admissions or ensuring proper disposal of diapers are essential steps to prevent future outbreaks.