Air China Flight 112

Air China Flight 112 was a scheduled international passenger flight on 15 March 2003 that carried a 72-year-old man infected with severe acute respiratory syndrome (SARS). This man would later become the index passenger for the infection of another 20 passengers and two aircraft crew, resulting in the dissemination of SARS north to inner Mongolia and south to Thailand. The incident demonstrated how a single person could spread disease via air travel and was one of a number of superspreading events in the global spread of SARS in 2003. The speed of air travel and the multidirectional routes taken by affected passengers accelerated the spread of SARS with a consequential response from the World Health Organization (WHO), the aviation industry and the public.

The incident was atypical, in that passengers sitting at a distance from the index passenger were affected and the flight was only three hours long. Until this event, it was thought that there was only a significant risk of infection in flights of more than eight hours duration and in just the two adjacent seating rows. Other flights at the time with confirmed passengers with SARS did not have the same extent of infection spread.

Some experts have questioned the interpretation of the incident and highlighted that some passengers may have already been infected. The role of cabin air has also come under question and the incident involving Flight 112 has led to some experts calling for further research into patterns of airborne transmission on commercial flights.

Background

The 2003 SARS epidemic was caused by the then newly emerging subtype of coronavirus (SARS-CoV), which was previously unknown in humans. It was first noted in Guangdong, China in November 2002. Three months later, it surfaced in Hong Kong, Vietnam, Singapore, and Canada. Transmission was primarily through inhalation of droplets from a human cough or sneeze and people affected presented with a fever greater than 38 °C (100 °F) and dry cough, typically appearing as atypical pneumonia.

By 28 February 2003, the SARS epidemic had reached Hanoi and was considered of global concern, causing the WHO headquarters in Geneva to issue a global health alert on 12 March 2003, the first since the 1994 India Plague epidemic. Led by the WHO, management of the event consisted predominantly of contact tracing, isolating the affected person and quarantining their contacts. The last known case of human-to-human transmission of SARS was in 2004.

Of the more than 8,000 people that were reported to develop SARS between November 2002 and July 2003 worldwide, more than half were from mainland China (particularly Beijing), 20% were healthcare workers and 29 countries reported 774 deaths. Although the overall fatality rate was 15%, it rose to 55% in those over 60.