Figure 1 is a vertical stacked column graph of the onset dates, from Saturday 12 October 2013 to Wednesday 13 November 2013, of the 17 cases, with dates of mass vaccination indicated. One case had onset date on Saturday 12 October. Two cases had onset on Tuesday 22 October. Three cases each had onset on Saturday 26 and Sunday 27 October. Arrows indicate the mass vaccination program on Thursday 31 October, Friday 1 November and Saturday 2 November. Five cases had onset on Saturday 9 November. Two cases had onset on Monday 11 November. One case had onset on Wednesday 13 November. Sixteen of the seventeen cases are shaded blue, indicating that vaccine strain virus was not detected. One of the cases with onset on 11 November is shaded red, indicating that vaccine-strain virus was detected from this case. A footnote states that this result does not preclude infection with wild-type virus.