Hand, foot and mouth disease (HFMD) has become a common infection. Causing mouth ulcers and spots on hands and feet, HFMD is a highly contagious infection that normally affects young children. Though it is less associated with older children and adults, it does affect them too.
HFMD is caused by virus that can be spread from person-to-person. It can be passed through direct contact with unwashed hands or surfaces contaminated with faeces. Plus, it can also be transmitted through contact with saliva or respiratory secretions.
The symptoms normally begin to develop between three to seven days after the initial infection. This period is known as the incubation period. Some of the symptoms are; fever, sore throat, blisters in the mouth and red spots on the hands and feet that will develop into blisters.
While the disease is less common in the United States, it is an outbreak in some countries in Asia that affects thousands of people. In China, the number of HFMD exceeded 90,000 in 2015 with HFMD fatalities reported. The number of HFMD also saw an increase in Japan. There were 4,252 cases reported between 12 March and 1 April 2015, which was a spike of 80% from the same reporting period in 2014. The number of HFMD cases reported in Singapore also prompted the U.S. Centers for Disease Control and Prevention (CDC) to issue travel notice to travellers in 2015.
HFMD is caused by the Enterovirus genus (group). This group of viruses includes polioviruses, coxsackieviruses, echoviruses and enteroviruses.
Coxsackievirus A16 is the most common cause of HFMD in the United States, but the other coxsackieviruses have been linked to the disease.
Enterovirus 71 is closely linked to HFMD and outbreak of the disease.
EV-71 has been implicated in HFMD outbreak in Southeast Asia.EV-71 is a non-polio enterovirus.
The more pathogenic EV-71 strain include encephalitis, aseptic meningitis, acute flaccid paralysis, pulmonary haemorrhage and myocarditis are linked to HFMD complications.
In December 2015, the China Food and Drug Administration (CFDA) approved the first vaccine against EV-71, an inactivated vaccine made by the Institute of Medical Biology at the Chinese Academy of Medical Sciences. The vaccine developed by the institute showed vaccine efficacy of 97.4%. Overall, the team identified 155 confirmed cases of EV-71 associated HFMD with four occurring in the vaccine group and 151 in the placebo group. This vaccine targeted children aged 6 to 71 months, with each child requiring a total of two doses one month apart. A second vaccine, also an inactivated vaccine, developed by Sinovac Biotech Ltd was approved in January 2016. The vaccine showed a 97.5% vaccine efficacy (6 month) and a 94.8% vaccine efficacy (12 month) against EV-71 associated HFMD cases and 89.3% (6 month) and 88% (12 month) for EV-71 associated cases. This vaccine targets children aged 6 to 35 months, with each child requiring a total of two doses one month apart. Despite differences in the seed strains used, manufacture processes and dosages, the Phase 3 trials conducted in various regions of China, have indicated satisfactory safety and efficacies again EV-71 related diseases and EV-71 associated HFMD cases.
These new vaccines have the potential to significantly reduce suffering and death from EV-71 disease in China and potentially, the rest of the world. However, manufacturing capacity and policy challenges remain for market entry and regulatory applications in other countries, especially those with large populations of infants and children.
Leong Kim Weng is a writer who writes about parenthood's articles. He uses this platform to reach out to the young parents. Writing for www.parentsdojo.com has given him the opportunity to learn and share interesting perspectives with others.