China hunts down Delta variant as Covid outbreak spreads to 14 province. Photo: Financial Times

The current outbreak, which first emerged in the eastern city of Nanjing, has spread to over half of China's 31 provinces and caused more than 1,000 symptomatic infections in three weeks, according to a CNN tally of the National Health Commission's daily reports.

Authorities have rushed to impose stringent lockdowns, mass testing, extensive quarantine and travel restrictions -- a strict playbook it has previously used to swiftly stamp out sporadic flare-ups.

Such measures have been deployed at a scale and intensity unseen in China since the initial outbreak in early 2020. Those officials who failed to implement the measures promptly or thoroughly enough are now finding themselves facing disciplinary actions.

Across the country, at least 47 officials, ranging from the heads of local governments, health commissions, hospitals and airports, have been punished for negligence, according to official statements and state media reports.

In Nanjing, the capital of Jiangsu province,15 officials were held accountable for allowing infections to spread at the Nanjing Lukou International Airport, according to a statement from the Communist Party's Central Commission for Discipline Inspection (CCDI).

The airport is where the outbreak is believed to have first started, with nine cleaners found to be infected on July 20 during a routine coronavirus test. Authorities have linked the cluster to a flight from Russia which arrived on July 10.

Three officials at the airport are under investigation by the provincial disciplinary authorities, and two of them have been detained. Others, including Nanjing's vice mayor, have received penalties ranging from suspension to severe warnings, according to the statement.

In Zhangjiajie, a tourist hotspot in southern Henan province famed for its pillar-like karst formations that inspired the movie Avatar, 18 officials were punished for their slack response in dealing with the flare-up, according to another statement from the CCDI.

Zhangjiajie was placed under citywide lockdown last month after a theater performance attended by thousands of people fueled concerns of a super-spreader event linked to the Nanjing cluster.

The city of Yangzhou, in neighboring Nanjing, has become a Covid hotspot. As of Tuesday, it has reported 394 symptomatic infections, including 26 "severe cases" and six patients who are critically ill.

On Sunday, Yangzhou's disciplinary commission issued warnings to six officials and criticized two others for mishandling a mass testing site, causing the virus to spread among test takers. So far, the cluster has caused more than 30 infections, according to state media.