This case recounts the efforts of Hong Kong public health authorities first to identify and then control a dangerous new flu virus not previously known to infect humans. The case focuses on the authorities' communication with the public, as they must seek to quell public fears notwithstanding their own incomplete knowledge of the disease. The case, too, describes the crisis management decision to undertake a massive slaughter of Hong Kong chickens, once they are shown to be the host of the deadly but difficult-to-transmit virus.