The Epidemic of Enterovirus 71 in Taiwan, 2011-2012

Yi-Chen Tsai, Chiu-Hsiang Lin, Wan-Ting Huang,Ni-Chun Yeh, Hung-Wei Kuo, Jen-Hsiang Chuang

2012 Vol.28 NO.5

Correspondence Author: Yi-Chen Tsai

  • Epidemic Intelligence Center, Centers for Disease Control, Taiwan


The enterovirus 71 (EV71) epidemic did not abate in late 2011 but continued to occur in early 2012. Because of the absence of large-scale EV71 outbreaks in Taiwan after 2008, most children less than three years of age have not been immunized to EV71. Therefore, the high proportion of community specimens tested positive for EV71 increases the likelihood of a larger outbreak of EV71 to occur after March 2012. From July 1, 2011 to March 1, 2012, Taiwan Centers for Disease Control had confirmed 70 patients with severe enterovirus infections (3 deaths); all were confirmed as EV71 infections. The median age of the 70 patients was 2 years (range 3 months to 8 years); 49 (70%) were aged less than three years. Clinical presentations of the 70 patients included myoclonus with autonomic dysfunction (n=42), acute encephalomyelitis (n=33), respiratory failure (n=4), and cardiac failure (n=1). The median interval from initial symptom onset to the recognition of severe presentations was 3 days (range 0.5–16 days); in 54 (77%) patients the intervals were 3–7 days. Although EV71 infections are generally mild and most children recover, few of them may develop severe complications or death. Because EV71 continues to circulate in the community, health care providers should pay particular attentions to the “warning signs” indicative of severe complications, such as “lethargy, consciousness disturbance, poor activity and limb weakness”, “myoclonic jerk”, “recurrent vomiting”, and “tachypnea or tachycardia”. These patients should be referred to the designed hospitals for appropriate clinical management.