Enterovirus 71

Virus, Non-Enveloped

VirusEnterovirus 71
StructureNon-enveloped
GenomeSingle stranded RNA, positive sense
FamilyPicornaviridae
Primary HostHumans
Disease(s) CausedHand, Foot, and Mouth Disease, meningitis
SymptomsHand, Foot, and Mouth Disease: fever, rash, loss of appetite, ulcers/blisters on mouth, hands, feet
Meningitis: fever, stiff neck, rash, vomiting, seizures, weakness
Potential ComplicationsParalysis
Transmission ModeFecal-oral
Sites of Community OutbreaksSchools, daycares, hospitals, workplace
Importance of Enterovirus 71

Enterovirus 71 (EV71) is a non-enveloped member of the Picornaviridae family with a single stranded RNA genome. EV71 is one of the causative agents of hand, foot, and mouth disease (HFMD), a disease that affects primarily infants and children. Outbreaks tend to occur more in tropical areas. Recently, outbreaks have been more common in Asia.

Symptoms of HFMD include fever, sore throat, and reduced appetite. Blisters in the mouth appear a few days after the onset of fever. Palms and soles of the feet may break out in a rash with blistering. In rare cases, neurological complications can occur, such as meningitis, encephalitis, and flaccid paralysis. The disease typically resolves itself in 7-10 days.

Importance of Disinfection: Survival of Enterovirus 71 on Surfaces and Potential for Transmission via Fomites

EV71 is a non-enveloped virus, which confers it a higher level of resistance to inactivation by environmental factors. Enteroviruses have been known to persist on surfaces at room temperature for several days. EV71 was shown to remain infectious dried on a plastic surface for up to 3 days in a hot, humid environment.

EV71 is highly contagious and is transmitted primarily via the fecal-oral route. Transmission can also occur by coming into contact with infected secretions, such as saliva and the fluid from blisters. Virus can be shed for up to 4 weeks via the respiratory tract and up to five weeks via feces. Contaminated fomites play an important role in the spread of EV71. For instance, a susceptible child could pick up EV71 from playing with toys shared with an infected child that have not been properly disinfected.

As with many non-enveloped viruses, EV71 is resistant to many disinfectants. A study has shown that at least 95% ethanol solution is necessary to produce a 99.99% reduction in EV71 on volunteers' hands after a 30 second contact time. 75% ethanol was not effective, nor was a common hand disinfectant product containing 0.5% chlorhexidine gluconate in 70% isopropanol. Another study showed that out of 16 disinfectants tested, only 2% glutaraldehyde, quaternary ammonium with 7% HCL, and 0.3-0.5% chloramine solutions were effective against Coxsackie B3, another enterovirus.

References
  • Chan, Y. F., and Bakar S. Abu. "Virucidal activity of Virkon S on human enterovirus." The Medical journal of Malaysia 60.2 (2005): 246.
  • Chang, S-C., et al. "Efficacy of alcohols and alcohol-based hand disinfectants against human enterovirus 71." Journal of Hospital Infection83.28 (2013): 8e293.
  • Sattar, S. A., et al. "Chemical disinfection of non-porous inanimate surfaces experimentally contaminated with four human pathogenic viruses."Epidemiology and infection 102.3 (1989): 493.
  • Solomon, Tom, et al. "Virology, epidemiology, pathogenesis, and control of enterovirus 71." The Lancet infectious diseases 10.11 (2010): 778-790.