The authors declare no conflict of interest.”
“Background Hand, Foot and Mouth Disease (HFMD) is a mild exanthematous and febrile disease, which often poses a persistent global public health problem. In recent years, outbreaks of HFMD have been reported from many parts of the world such as Malaysia [1, 2], Taiwan [3–6], Singapore , Mainland China , Brunei , Western Australia , the Unites States  and Germany . The two major etiological agents for HFMD are
Enterovirus 71 (EV71) and Coxsackievirus A16 (CA16), which belong to the Enterovirus genus of the Picornaviridae family  and usually co-circulate during HFMD outbreaks [4, 14, 15]. In addition to INK 128 cost HFMD, EV71 is also associated with herpangina, myocarditis, encephalitis, aseptic meningitis, acute flaccid paralysis, and pulmonary oedema or haemorrhage. EV71 usually infects children, while sometimes it can infect adults by intra-familial transmission [16, 17]. Generally, children and adults infected present different symptoms. selleck products Data from a recent study indicated that 21% of
EV71-infected children experienced severe complications including central nervous system (CNS) complications and cardiopulmonary failure. By contrast, 53% of infected adults were asymptomatic, and all symptomatic adults recovered completely from uncomplicated illness . However, there were several reports about adults infected with severe complications. 4��8C It was reported that in November 2006, a 37-year-old woman suffered from acute encephalitis due to intra-familial transmission
of EV71 . In 2000 a 19-year-old man even died from EV71 encephalitis in Singapore . CA16 appeared to have been attracting very little interest probably due to its association with often mild and benign clinical symptoms. Therefore, there had been much less data about CA16 than EV71. Both EV71 and CA16 were divided into several subtypes by vp1s (referred to nucleotide sequences, the same below) or vp4s (referred to nucleotide sequences, the same below). Data from molecular epidemiological studies indicated that EV71 consisted of 3 genotypes A, B (B0~B5) and C (C1~C5) [14, 19–24]. However, C4 was being proposed as genotype D recently [25, 26]. Based on phylogenetic analysis of vp4s, CA16 was classified into three distinct genetic lineages A, B, and C. Lineage A was represented by only one isolate of the prototype G10 . In a recent report, CA16 was divided into two distinct genogroups A and B based on vp1s, which was probably a more accurate description for vp1s containing more nucleotides and genetic information. The prototype G10 was the only member of genogroup A. Genogroup B was divided into two separate lineages (1 and 2) . In fact, lineage B and C viruses in the analysis based on vp4s represented lineage B1 and lineage B2 viruses, respectively, in genogroup B as determined using complete vp1 sequences .