Epidemiology of causative agents for Enterovirus infections among children aged under 5 years old in the sentinel sites of hospital-based laboratory surveillance network, Fiscal Year 2017

Abstract

Hand, foot, and mouth disease (HFMD) is a major public health problem. Most of cases are usually diagnosed based primarily on clinical symptoms without laboratory confirmation from specimen collection. Bureau of Epidemiology (BOE), Department of Disease Control (DDC), has conducted sentinel sites of hospital-based laboratory surveillance to monitor causative agents causing HFMD and enterovirus infections among children aged under 5 years old. There were 27 hospitals participating as the sentinel sites during the fiscal year of 2017. All samples of suspected HFMD cases and enterovirus infections were sent to the Emerging Infectious Disease Health Science Center, Chulalongkorn Hospital, for reverse transcription polymerase chain reaction (RT-PCR) testing. There were 707 cases (746 samples) being tested for those pathogens using RT-PCR. More samples were collected and sent for laboratory analysis in October 2016 than any other periods. Most of the samples were throat swab (92.66%). The causative agents were detected in 357 out of 746 samples (47.86%). Coxsackievirus was mostly detected (62.75%), followed by Enterovirus 71 (30.81 %), and others such as Echovirus and Rhinovirus (6.44%). Subtypes of Coxsackievirus were identified and revealed that the highest proportion of detection was Coxsackievirus A 16 (39.64%). From this study, one death due to Enterovirus 71 was confirmed. Data from a questionnaire completed by parents of the cases were extracted. There were 390 (55.24%) parents who responded to the questionnaire interview. Of all the pediatric cases whose specimens had been collected, pre-kindergarten children accounted for 48.87%, while those in kindergarten age group represented 52.97%. Most common symptoms were mouth blisters or ulcers (76.15%), fever (74.62%), rash on the palms, soles of the feet, upper and lower limbs or buttocks (58.21%). Based on chart review, complications of myocarditis were observed in 1 case, pneumonia in 2 cases, and encephalitis in 1 case. Medical staff at each hospital can play a crucial role in establishing cooperation from other health staff to ensure specimen collection is carried out to meet the established target. In the meantime, a hospital screening point can also play a significant role in helping detect an unusually large number of suspected HMFD cases or a cluster of HFMD cases in the same local area at the early stages of the outbreak. Expanding the network of laboratories capable of performing diagnosis to detect these health threats to cover all the regions or all medical science centers across the country can be helpful to detect the outbreak at its early stages. This will in turn ensure early medical treatment so as to prevent complications. Development of diagnostic techniques that are accurate, easy and convenient to use can also benefit field investigation, consequently resulting in early detection and timely and effective response.