SARS and COVID-19: Pandemics at the Speed of Flight

Air travel means a disease can reach any major city within a day. In 2002 a new coronavirus disease, SARS, emerged in southern China; in February 2003 an infected doctor staying at a Hong Kong hotel unknowingly spread it to guests who carried it to Canada, Vietnam and Singapore. Coordinated tracing and isolation contained SARS by July 2003, after about 8,000 cases. COVID-19, caused by a related virus, was first identified in Wuhan, China, in late 2019.

The WHO declared a Public Health Emergency of International Concern on 30 January 2020 and described the outbreak as a pandemic on 11 March 2020. Countries responded with lockdowns, travel restrictions and, from December 2020, vaccines developed at record speed. The COVAX initiative aimed to share vaccines fairly, but richer countries received doses much sooner. These pandemics show how connection spreads disease and how inequality shapes responses.