Dr. Jamal I-Ching Sam
Department of Medical Microbiology,
Faculty of Medicine, University of Malaya,
Enteroviruses have been the focus of study in Malaysia since 1992 as part of surveillance of acute flaccid paralysis cases. There have been no wild-type polio cases since 1992, while non-polio enteroviruses such as coxsackieviruses A and B, and enterovirus A71 (EV-A71) have been reported. Greater attention was paid to hand, foot and mouth disease (HFMD) viruses following outbreaks of fatal EV-A71 in 1997, followed by further national outbreaks in 2000, 2003, 2006, 2008/9, and 2012, all associated with mortality. HFMD was declared a notifiable disease in October 2006, and national guidelines on public health management of HFMD were issued in 2007.
Seroprevalence studies suggest that the main driver of this cyclical pattern of outbreaks is population immunity to EV-A71, although the contributions of genetic variation and other environmental factors (which may explain apparent peaks in May-June) are unclear. Non-EV-A71 viruses may cause a large proportion of cases in some years, such as coxsackievirus A16 in 2007 and 2015, and coxsackievirus A6 in 2012/2013. However, as virological confirmation and typing is not routinely performed for all cases, there is a significant gap in knowledge of the causative agents in HFMD.
The content is authorized by Dr. Jamal I-Ching Sam on October 29, 2017.