China’s aviation authority suspended a China Southern Airlines flight route on Sunday after 17 passengers on a June 11 flight tested positive for the coronavirus.
It is the regulator’s first use of its new “circuit breaker” flight regulations, which came into effect on June 4 as domestic carriers expanded flights and days before China reintroduced international flights after months of border restrictions to prevent the import of the virus.
The Civil Aviation Administration of China (CAAC) suspended the airline’s Dhaka, Bangladesh, to Guangzhou, China, flight—the weekly flight CZ392—for four weeks starting June 22 because of the infected passengers. The airline’s other flights won’t be affected.
The circuit-breaker rules mandate that all incoming passengers to China must be tested for the coronavirus. If five or more passengers on the same flight test positive, that airline will be suspended for one week. If 10 or more passengers on one flight test positive, the suspension increases to four weeks. The rules apply to all flights into China, and passengers are tested on arrival.
The CAAC on June 8 relaxed its flight restrictions for international carriers after the U.S. threatened to block Chinese airlines in retaliation for China’s ban, which included the three major U.S. airlines, Delta Air Lines, United Airlines, and American Airlines.
International carriers are currently limited to one flight per week to one city in China of their choice. If none of their passengers tests positive for the coronavirus for three consecutive weeks, the airlines will be able to increase capacity to two flights per week.
The circuit breaker is designed to cut the number of coronavirus cases imported into China. China Southern Airlines had been operating two flights per week between Dhaka and Guangzhou since the beginning of June. Both those flights will be canceled under the circuit-breaker rule.
The airline’s domestic routes won’t be affected by the measure. It will be able to resume its Dhaka-Guangzhou route when the four-week ban elapses.
The China Southern Airlines flight suspension comes as China grows more wary of a “second wave” of COVID-19. Beijing reported a new cluster of 79 local infections this weekend, prompting authorities there to lock down parts of the city.
Beijing had not recorded a local case in 56 days before the new outbreak, which is tied to a large seafood market. Local cases are especially worrisome because they suggest the virus has been spreading undetected among city residents, making the outbreak harder to trace. Imported cases, on the other hand, are more easily attributable to travelers.
China’s air travel industry, battered by nationwide travel bans, on Friday recorded 1 million daily domestic passenger trips for the first time since January. The tally represents 61.5% of the total trips made on the same day last year, before the pandemic.
Correction: an earlier version of this story stated that China Southern Airlines was a member of the SkyTeam Alliance. China Southern left the SkyTeam Alliance on Jan. 1, 2019.
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