Epidemiology of hand, foot and mouth disease outbreaks in Sabah, Malaysia: One year cross-sectional study

Introduction

Hand, foot and mouth disease (HFMD) is a contagious illness typically caused by enteroviruses. However, the causative agent of HFMD can vary by type and region. To better understand the epidemiological characteristics, we conducted a retrospective study of HFMD outbreaks in a Malaysia state over the course of one year.

Material and Methods

A cross-sectional descriptive analysis was conducted on all notified HFMD outbreaks and confirmed HFMD cases within Sabah state in Malaysia via the national public health disease surveillance system. Clinical specimens (throat swabs, ulcer swabs, rectal swabs or stool cultures) taken during the outbreaks were tested by polymerase chain reaction and positivity yield rates were reported.

Results

A total of 215 HFMD outbreaks occurred predominantly in childcare centres (40.9%), involving 1232 cases in the state. The most commonly affected age group was children aged 0 to 4 years, with males accounting for 56.0% of the cases. The majority were of native ethnicity (76.4%), followed by Chinese ethnicity (8.6%). No fatalities were detected. Of the 485 clinical specimens sent, 41.0% tested positive for viruses, with stool cultures exhibiting the highest positivity rate. Among the positive specimens, 52.3% tested positive for PanEnterovirus, followed by Coxsackievirus A16 (24.6%) and Enterovirus 71 (23.1%). Further viral isolation tests on PanEnterovirus samples revealed that 1.9% were identified as Coxsackievirus A16.

Discussion

During outbreaks of HFMD in the Malaysia state, male children under the age of five were notably affected. It was reported that the duration of viral shedding lasted longer in stools compared to other swab samples, potentially leading to a higher diagnostic yield. The co-circulation of both Coxsackievirus A16 and Enterovirus 71 in the state highlights a potential risk to public health, emphasizing the importance of regular laboratory surveillance in the country.