Enterovirus 71 (EV71) is a member of the family picornaviridae. EV71 and coxsackieviruses A16 and A10 are known as common causative viral agents for hand, foot, and mouth disease (HFMD) in humans. However, EV71 is the only causative viral agent associated with significant morbidity and mortality, owing to its involvement of the central nervous system (CNS). The neurovirulence of EV71 was first noted in 1975 in Bulgaria when 44 patients died of a polio-like disease. Epidemics of CNS diseases caused by EV71 were reported subsequently in Australia, Europe, and Asia.
In 1998, a large outbreak of HFMD caused by EV71 occurred in Taiwan. More than 80 children died of encephalomyelitis, which clinically manifested as shock syndrome and pulmonary edema. After this outbreak of HFMD, EV71 infection became endemic in this area, causing 140 deaths each year in 2000 and 2001. With the tendency of globalization, EV71 may eventually spread to other parts of the world.
A joint UK and Chinese team working at the UK's national synchrotron facility near Oxford determined the structure of EV71 in 2012. Researchers observed movements resembling breathing in the virus, and found that this accompanied the infection process, together with a small molecule picked up from the body's cells and used to switch state. This particular molecule must be discarded in order to start an infection, and new research will be aimed at creating a synthetic replica that would bond strongly to the virus and stop the infection process. EV71 contains four viral proteins which act in different functions. Study indicates that EV71 infects host cells through VP1 produced by the splitting of precursor of VP0. Figure 1 shows EV71 structure:
Fig. 1 Model of Enterovirus 71 Virus