On Sunday, 13,146 local COVID-19 cases were reported in mainland China, 11,691 cases of which are asymptomatic. The number has been the highest since the latest outbreak, which has infected more than 100,000 people. 

The region that is most severely hit is Northeast China's Jilin Province, and the curve has not seemed to be declining. The mass majority of cases in China have been found in recent days where a new Omicron variant was discovered, in East China's Jiangsu Province, neighboring Shanghai.

438 cases were confirmed particularly in Shanghai on Sunday, among which 7,788 are asymptomatic, as per Chinese Vice Premier, Sun Chunlan, who made an official visit to the city on Saturday to help battle the virus.

Zhang Boli, an academic from the Chinese Academy of Engineering and head of the Tianjin University of Traditional Chinese Medicine (TCM) said that the Omicron variant can still be controlled if proactive measures are taken, adding that the significant number of asymptomatic cases in the current outbreak is due to the characteristics of the variant itself, but is also linked with the speedy mass testing rollout. 

Zhang noted that the increase in vaccination has increased herd immunity; consequently, those getting infected are showing lighter or no symptoms. According to health officials, the Chinese mainland had given out a total of over 3.27 billion doses of COVID-19 vaccine as of Sunday.

However, the chief epidemiologist of China's Center for Disease Control and Prevention, Wu Zunyou, disagreed and said that the reason China witnesses more asymptomatic cases and less severe cases is not due to the characteristics of Omicron, as other countries are witnessing more deaths caused by Omicron compared with that of Delta. 

"It is the result of our effective epidemic prevention work, namely the early identification of the epidemic, timely response, and the whole-process management for all infected people, including the asymptomatic cases, giving them traditional Chinese medicine to improve their immunity and prevent severe infection," Wu said on Friday. 

Unlike Zhang Boli, Wu believed that epidemic control would be challenging for a city with infections exceeding 10,000 in a short period of time. First, more patients would need treatment and more people who had been in close contact with infected people would need to be quarantined, he explained. Also, medical staff would be put under increased pressure. 

Shanghai taking measures to limit the spread of the virus

The hospital system in Shanghai is on the verge of being overwhelmed, but medical staff and supplies from all over the country are flooding in to help resist the outbreak. Food and other daily needs are also being sent to maintain a state of normalcy for the residents. 

Antigen self-testing kits are being distributed to help in screening across the city and boost efficiency, according to local infectious disease expert Zhang Wenhong and prevent the transmission in a timely manner. 

New variant

Suzhou, in Jiangsu Province, discovered a confirmed coronavirus patient infected with a mutation VOC/Omicron variant BA.1.1. The variant was unidentified in previously found strains worldwide, which poses new threats to the already critical situation in the region.

Jilin Province, another hard-hit region by the epidemic, recorded 4,455 cases on Sunday.