Figure 4 explains the timeline that takes place over a 21 day period, tracing the epidemiological information for IP#2, beginning on January 16, 2009. On January 31, 2009, IP#2 was quarantined as a result of being located within a 3 km perimeter of IP#1/IP#1a. The final entry on the timeline, February 5, 2009, marks the date that submitted samples were found RT-PCR positive for H5, which means a presumptive case of NAI.