Clinical and molecular characterization of hand-foot-and-mouth disease in Thailand, 2008-2009.

Hand-foot-and-mouth disease (HFMD) is caused by a group of enteroviruses, most commonly coxsackievirus A 16 (CA16) and enterovirus 71 (EV71). In general, the disease is mild and self-limited except in the case of EV71 infections, which may incur serious complications. This research focused on virus characterization of HFMD cases in Thailand from 2008-2009, related clinical findings and complications of specific enterovirus subtypes. Specimens (stool, vesicle fluid, throat swab/sputum) from 48 cases were collected during 2008-2009. Reverse transcriptase-polymerase chain reaction (PCR) followed by direct sequencing and phylogenetic analysis served to detect enterovirus and determine subtype. Enterovirus was found in 58.3% (28/48) of cases, specifically EV71 (n=23), CA16 (n=4), and CA10 (n=1). Two patients infected by EV71 had brainstem encephalitis (one death). Eight patients required hospital admission due to dehydration. Of these, 3 were PCR positive for EV71, 1 for CA16, and the reminder negative. This study demonstrated EV71 as the most prevalent present cause of HFMD in Thailand in 2008-2009. Potentially fatal complications of HFMD should be taken into consideration. Surveillance of epidemiology and monitoring of disease severity should be continued, and as a prevention measure, sanitation and hygiene should be improved.