China Airlines crew COVID-19 cluster, also known as the China Airlines pilot cluster or the China Airlines Novotel cluster, was a cluster of COVID-19 infections associated with China Airlines in Taoyuan City, Republic of China (Taiwan). It was the second cluster involving infected airline pilots in Taiwan since the outbreak of the COVID-19 pandemic.
On 26 February 2021, the Central Epidemic Command Center (CECC) announced that crew members of Taiwanese airlines, classified as frontline personnel with high exposure risk, were eligible for publicly funded COVID-19 vaccination under the third priority category among the first three groups. Critics argued that pilots should have been prioritized for vaccination. In response, Minister of Health and Welfare Chen Shih-chung stated that the vaccination priority list had long been announced and questioned why objections had not been raised earlier. On 24 April, the CECC criticized China Airlines for the slow pace of vaccination, noting that only 44 of its 1,720 pilots had been vaccinated, compared to 235 pilots at EVA Air, more than five times as many. Starlux Airlines had also not encountered problems in arranging vaccination appointments.
As of 12 May 2021, according to case charts released by the CECC, the pilot cluster consisted of 44 confirmed cases, including 13 pilots, seven antibody-positive pilots, ten family members of pilots, two family members of antibody-positive pilots, five quarantine hotel employees, three family members of quarantine hotel employees, one quarantine hotel contractor, two flight attendants, and one shuttle bus driver employed by a quarantine hotel.
The Novotel hotel complex consisted of Building 1 (the main building) and Building 2, with Building 2 having been registered with the Taoyuan City Government as a quarantine hotel. However, due to insufficient room capacity in Building 2 beginning in February 2021, the hotel adopted a system of managing designated rooms in separate sections without applying to the city government for approval as a "multi-floor quarantine hotel". Some quarantined flight crew members were transferred from Building 2 to the seventh- and eighth-floor staff dormitories of Building 1, while ordinary guests were also accommodated on the eighth floor.
Hotel staff did not maintain clear separation between quarantined and non-quarantined individuals. The kitchen and a temporary waste disposal area were located on the same floor, and kitchen staff and housekeeping personnel shared elevators while simultaneously serving both quarantined guests and ordinary customers. Employees delivered meals wearing disposable raincoats purchased from convenience stores that provided inadequate protection. Because of late check-out and early check-in arrangements, housekeeping staff were sometimes left with only one hour to prepare rooms, and some rooms were reassigned to new guests without being disinfected. In addition, personnel self-management measures were found to be inadequate.
On 13 May 2021, genomic sequencing revealed that the subsequent Luzhou, Wanhua, and Yilan clusters involved the same SARS-CoV-2 B.1.1.7 lineage as the China Airlines Novotel cluster. The CECC concluded that the clusters might be related, although no epidemiological links had yet been identified. Since both the Wanhua cluster and the China Airlines cluster involved identical viral sequences, experts inferred that they represented the same transmission chain detected in different locations and were likely part of a single large community outbreak in Taiwan rather than multiple parallel chains of transmission. However, authorities emphasized that identical genomic sequences or the presence of the Alpha variant did not necessarily establish a direct connection to the China Airlines cluster, and that further investigation was required to determine the source. At the time, the related outbreaks included eight cases linked to the Yilan amusement arcade cluster and twenty cases associated with the Luzhou Lions Club cluster, which subsequently gave rise to seven Wanhua tea-house-related cases.
On 14 May 2021, the cluster involving pilots, hotel employees, and other associated individuals concluded with a total of 37 infections, while 412 individuals had completed quarantine and been released.
Timeline On 20 April, a male Indonesian cargo pilot in his 40s employed by China Airlines traveled to and from Australia on cargo duty. After developing symptoms of an itchy throat, he tested positive for COVID-19 in Australia.
On the same day, two imported cases (Cases 1078 and 1079), both China Airlines cargo crew members, were announced in Taiwan. The two had traveled together to and from the United States on duty on 14 April and stayed in quarantine at a hotel overseas until returning to Taiwan on 16 April. Case 1078 developed symptoms on 18 April, while Case 1079 developed symptoms on 17 April. Investigations into the sources of infection were ongoing. A total of 131 contacts were initially identified, of whom two were placed under home isolation and 129 under self-health management.
On 23 April, the Central Epidemic Command Center (CECC) received an official report from China Airlines and immediately initiated contact tracing and testing operations related to the Australian-confirmed pilot and his activities in Taiwan. Two contacts subsequently tested positive: Case 1090, a teenage male household member of the Indonesian pilot confirmed in Australia, and Case 1091, a male colleague in his 50s. Both were confirmed on 23 April. A total of 58 contacts were initially identified, including the two positive cases, eight who tested negative, 23 awaiting results, and 25 awaiting testing. Contact tracing remained ongoing. Expanded testing of cargo crew members under quarantine or self-health management was also initiated.
On 24 April, epidemiological investigations into the Australian-confirmed case continued. One retrospective testing case, Case 1092, a male cargo crew member in his 40s, tested positive. He had flown to New Zealand and the Netherlands between 9 and 16 April and remained asymptomatic during the trips. Tests conducted on 9 and 13 April were negative. After returning to Taiwan on 16 April, he completed three days of quarantine and tested negative upon release on 19 April. On 22 April, he flew to Japan and returned the same day, beginning another three-day quarantine period. During the afternoon, he underwent retrospective testing as a contact of the Australian-confirmed pilot and tested positive (Ct value 35; second sample Ct value 23; serum antibody negative). He was confirmed on 24 April. In response to the pilot infections, comprehensive nucleic acid and serological testing for all China Airlines flight crew members was launched on the same day.
On 25 April, another retrospective testing case, Case 1100, a male cargo crew member in his 50s, tested positive. In addition, Case 1101, a male cargo pilot in his 30s who had completed quarantine, was confirmed. Case 1100 had traveled to the United States between 13 and 17 April and returned to Taiwan on 18 April, undergoing three days of quarantine. He tested negative at his own expense on 21 April but later tested positive during retrospective testing related to the Australian-confirmed pilot. Case 1101 had traveled to Germany with three other crew members on 18 April and quarantined at a hotel in Germany before returning to Taiwan on 22 April. His test upon completing quarantine on 24 April returned positive (Ct value 28; repeat test Ct value 34; serum antibody negative), and he was confirmed on 25 April. Investigations into the source of infection remained ongoing. A total of 1,272 individuals were expected to be tested.
On 26 April, two additional retrospective testing cases were confirmed. Case 1102, a male cargo pilot in his 30s, had traveled to the United States between 6 and 9 April and returned to Taiwan without symptoms during his three-day quarantine, testing negative on 14 April. He flew to the United States again between 19 and 22 April and remained asymptomatic during quarantine upon his return. Beginning on 24 April, he developed symptoms including cough and fever (37.8 °C). A test conducted on 25 April before the completion of quarantine returned positive (Ct value 18), and he was confirmed on 26 April. Case 1105, a male cargo pilot in his 40s, had traveled to the United States between 8 and 10 April and tested negative on 15 April after returning to Taiwan. He reported experiencing loss of appetite beginning on 19 April. He tested positive (Ct value 32) on 25 April through the flight crew testing program and was confirmed on 26 April. Investigations into the source of infection continued. Three household contacts were placed under home isolation, while workplace contacts were being traced.
On 27 April, one additional confirmed case, Case 1111, was announced. She was an Indonesian woman in her 40s who had been placed under home isolation on 21 April as a contact of the pilot confirmed in Australia on 20 April and Case 1090, the teenage household member confirmed on 23 April. Tests conducted on 21 and 22 April were negative. On 26 April, she developed symptoms including dry throat, body aches, dizziness, a bitter taste in the mouth, nausea, and insomnia. She tested positive (Ct value 22) and was confirmed on 26 April. One household contact had their home isolation period extended until 10 May.
On 28 April, one imported and two locally transmitted cases were announced. The two local cases were Case 1113, a teenage male household member of a pilot who had tested positive for antibodies on 27 April, and Case 1114, a woman in her 40s from the same household. Neither had recent travel histories or symptoms. Case 1113 tested positive during contact tracing on 26 April (Ct value 36; repeat test on 27 April with Ct value 41; IgM negative and IgG positive antibodies) and was confirmed on 28 April. Apart from the pilot, the other two household members tested negative by PCR but were both IgM negative and IgG positive. Case 1114 tested positive during contact tracing on 26 April (Ct value 34; repeat test negative on 27 April; IgM negative and IgG positive antibodies). Aside from the pilot, the remaining two household members tested negative by PCR; one was IgM negative and IgG positive, while the other tested negative for antibodies.