Figure 1. Chronology of major events during the early phase of the coronavirus disease epidemic and laboratory-confirmed cases in Hong Kong, December 30, 2019–February 14, 2020. A, unexplained pneumonia reported in Wuhan, China; B, HK begins temperature screenings at border checkpoints for travelers from Wuhan; C, HK launches preparedness and response plan for novel infectious disease of public health significance, serious response level; D, first death reported in Wuhan; E, World Health Organization (WHO) names disease 2019-nCoV acute respiratory disease and the virus 2019-nCoV (refer to Y for subsequent renaming); F, China confirms human-to-human transmission; G, HK introduces health declaration form system on inbound travelers by air from Wuhan; H, WHO declines to declare COVID-19 a public health emergency of international concern; I, first first confirmed COVID-19 case in HK, halt of sale of high-speed rail tickets to and from Wuhan; J, HK activates emergency response level; K, HK closes public leisure and cultural facilities until further notice; L, WHO declares COVID-19 a public health emergency of international concern; M, United States declares COVID-19 a public health emergency, imposes entry restriction; N, HK imposes 4-week school suspension, 1-week extension for home-office arrangement for civil servants; O, first COVID-19 death outside China in the Philippines; P, HK medical workers strike to call for border shutdown; Q, first COVID-19 death in HK, closure of 4 more border control points; R, 46 foreign airlines cancelled flights to mainland China; S, HK implements further port hygiene measures; T, HK offers home-office arrangement for civil servants until February 16; U, first death of a doctor in China (Wuhan); V, HK begins mandatory 14-day quarantine on persons entering from China; W, HK reports COVID-19 cluster involving 9 people in a gathering on January 26; X, HK reports COVID-19 cluster involving 5 residents (2 families) in the same building; Y, WHO and ICTV rename disease COVID-19 and virus SARS-CoV-2; Z, HK extends home-office arrangement for civil servants until February 23, school suspension until March 16. HK, Hong Kong.