Changing epidemiology of human enteroviruses (HEV) in a hand, foot and mouth disease outbreak in Vellore, south India

Grace Mary George; Hubert Darius-J Daniel; Lydia Mathew; Dincy Peter; Leni George; Susanne Pulimood; Asha Mary Abraham; Shoba Mammen

doi:10.1016/j.ijmmb.2022.04.005

Changing epidemiology of human enteroviruses (HEV) in a hand, foot and mouth disease outbreak in Vellore, south India

Indian J Med Microbiol. 2022 Jul-Sep;40(3):394-398. doi: 10.1016/j.ijmmb.2022.04.005. Epub 2022 Apr 28.

Authors

Grace Mary George¹, Hubert Darius-J Daniel¹, Lydia Mathew², Dincy Peter², Leni George², Susanne Pulimood², Asha Mary Abraham¹, Shoba Mammen³

Affiliations

¹ Department of Clinical Virology, Christian Medical College, Vellore, India.
² Department of Dermatology, Christian Medical College, Vellore, India.
³ Department of Clinical Virology, Christian Medical College, Vellore, India. Electronic address: shobamammen@cmcvellore.ac.in.

PMID: 35491281
DOI: 10.1016/j.ijmmb.2022.04.005

Abstract

Purpose: Hand Foot and mouth disease (HFMD) is a major childhood exanthematous disease causing outbreaks that have become a major public health threat in recent years. In Vellore district of Tamil Nadu, south India, occasional outbreaks are common among the paediatric age group, most commonly in those under 5years of age (U5s). CoxsackieA6, A4, A5, A9, A10, B2 and B5 are the common serotypes causing outbreaks. This study aimed to identify the molecular serotype of the causative agent, co-circulating in this region.

Methods: Adapting the WHO case definition, cases during an HFMD outbreak between October and December 2017, were identified by a clinical criterion of fever, mouth ulcers and rash in the extremities. Vesicle fluid from these lesions were collected in viral transport medium and transported cold to the Clinical Virology laboratory of a tertiary care hospital in Vellore. Identification of the causative agent was undertaken by two real time PCRs (EV1 and EV2) followed by sequencing the VP1-2C region and constructing a phylogenetic tree.

Results: Among the 31 HFMD patients included in this study, 23 (74.2%) were U5s, 3 (9.7%) were between 6 and 15 years and the remaining 5 (16.1%) were adolescents (>15 yrs). The outbreak ran a mild clinical course, with 22(71%) patients having fever as a prodromal symptom. Papulovesicular lesions characteristic of HFMD were present on all 31 (100%) patients' palms and soles, buttocks of 19 (61.3%), oral mucosa of 12 (38.7%), and all over the body in 4 (12.9%) patients. Coxsackie A6(75%) and Coxsackie A16(25%) were the pathogens associated with this outbreak.

Conclusions: Changing epidemiology of HFMD was seen in this outbreak since; other serotypes apart from the classical Coxsackievirus serotypes causing HFMD outbreak were also found co-circulating. EV1 PCR was a better screening assay than EV2 PCR in this region. Continued surveillance and molecular serotyping are necessary for HFMD outbreaks in any region.

Keywords: Changing epidemiology; Coxsackie A16; Coxsackie A6; Hand foot mouth disease.

MeSH terms

Adolescent
Child
Child, Preschool
China / epidemiology
Disease Outbreaks
Enterovirus* / genetics
Hand, Foot and Mouth Disease* / epidemiology
Humans
India / epidemiology
Phylogeny
Real-Time Polymerase Chain Reaction