We summarized the characteristics of patients from each report in Table 1 . The mean age of the pooled patients from all studies was 8.0 ± 4.4 years, and mean ages of the patients were significantly different among the different reports (p = 0.032). For the pooled data, the proportion of patients who showed ARDS or respiratory failure during hospitalization was 75%; this proportion was also significantly different among the different reports (p = 0.014). Overall, the CFR was 69.4%, and no significant difference between reports was observed. For the pooled data, median number of days from onset to admission was 6.0 and the median number of days from onset to outcome was 14.0; there no significant differences among the reports for both data sets.