Epidemiology and Control of Hand, Foot and Mouth Disease in Singapore, 2001-2007

Abstract

Introduction: We reviewed the epidemiology of hand, foot and mouth disease (HFMD) in Singapore after the 2000 epidemic caused by Enterovirus 71 (EV71), with particular reference to the cyclical pattern, predominant circulating enteroviruses and impact of prevention and control measures in preschool centres. Materials and Methods: We analysed the epidemiological data from all clinical cases and deaths of HFMD diagnosed by medical practitioners and notified to the Ministry of Health, as well as laboratory data on enteroviruses detected among HFMD patients maintained by the Department of Pathology, Singapore General Hospital, and the Microbiology Laboratory, KK Women’s and Children’s Hospital from 2001 to 2007. Results: The incidence rate was highest in the 0 to 4 years old age group, with males being predominant. Three deaths were reported between January and February 2001. Nationwide epidemics occurred periodically; the predominating circulating virus was Coxsackievirus A16 (CA16) in the 2002, 2005 and 2007 epidemics, and EV71 in the 2006 epidemic. During the epidemic years between 2005 and 2007, 2 peaks were observed. The number of institutional outbreaks had increased 10-fold from 167 in 2001 to 1723 in 2007, although most of these outbreaks were rapidly brought under control with an attack rate of less than 10%. Conclusion: HFMD remains an important public health problem in Singapore with the annual incidence rate per 100,000 population increasing from 125.5 in 2001 to 435.9 in 2007, despite stringent measures taken in preschool centres to prevent the transmission of infection. A high degree of vigilance should be maintained over the disease situation, in particular, surveillance of EV 71 which continues to cause severe complications and deaths in the region. Key words: Coxsackievirus A16, Enterovirus 71, Epidemic, Preschools