Fig 2. Age-specific EV71 serostatus in Taiwan in 1997, 1999, 2007, and 2017.

Infants did not have significantly different seropositive rates among different years (p = 0.62). The rates in 2–11-year-old children were significantly lower in 2007 and 2017 than those rates in 1997 and 1999 (p<0.001). The seropositive rate of the 6- to 19-year-olds in 2017 was significantly lower than those rates in 1997, 1999 and 2007 (p<0.001). The seropositive rates of 20- to 29-year-old adults were not significantly different among the 4 different years.