Zhang Wenhong, head of the infectious disease department at Fudan University's Huashan Hospital in Shanghai, said it is vital to stay confident, calm and clear-minded, and to not give up the fight against the virus.

"The infections in the mainland are still in the early stage of an exponential rise," he said on the microblogging platform Sina Weibo. "Because of a surge of cases in a relatively short span, many regions have appeared to be flustered."

With local authorities implementing targeted lockdowns and speeding up screening of key areas, Zhang said the virus' spread will eventually be slowed.

Based on discussions with virologists at the University of Hong Kong, he said the virulence of the new strain has decreased, and that fully vaccinated people and those with normal immune systems are unlikely to develop serious symptoms.

Only 0.1 percent of the 2,266 patients being treated in Shanghai over the past six months have been classified as having severe cases, and no one has died, he added.

Based on Hong Kong data, the death rate of people who aren't fully immunized is 23 times higher than those have received two shots.

Though the virus has become milder and less lethal, Zhang argues against relaxing virus containment policies.

"If China opens up too quickly, many people will get infected quickly, leading to a staggering number of hospitalizations, strained medical systems and an impact on society," he said. The consequences would be unimaginable for the elderly and those with underlying health problems who have not been vaccinated for fear of side effects, he said.

While it is vital for China to continue its strategy of achieving zero infection and bring the wave of Omicron infections under control, "it doesn't mean that we will impose lockdowns and mass testing persistently", he said.

When the outbreaks are stamped out, it is essential to seize the window of opportunity to develop smarter and more sustainable strategies, such as launching an extensive booster vaccine plan for seniors, ensuring the supply of oral antiviral medicine and affordable home testing kits, and developing fully trained triage medical services and home quarantine protocols, he said.