"I still have great confidence in the COVID-19 pandemic finishing by the end of 2022," Zhang Wenhong, a Shanghai-based top infectious disease expert, said in an interview with China Media Group on January 15.

"This might be the last 'cold winter,'" he said.

Zhang said whether it is due to the level of herd immunity, the immune barrier established by vaccines or the expected launch of new treatment drugs in 2022, the end of the pandemic is near.

When asked about concerns surrounding the Delta and Omicron variants of SARS-CoV-2, the virus that causes COVID-19, Zhang said they are merely mutations of the same virus and all viruses change over time. However, it would be of serious concern if SARS-CoV-2 had mutated with other coronaviruses, he said, adding that "it's very unlikely."

"I believe that with the experience we have accumulated in dealing with COVID-19, we will still be able to cope with it no matter how the virus mutates in the future," he said.

Is Omicron less of a threat?

Countries with relatively low infections "better be invested in keeping that number very, very low," said an official from the World Health Organization (WHO). In this context, China faces great challenges to maintain the "dynamic zero-COVID" policy as Omicron ravages the world, Zhang said. 

Omicron's lethality cannot be overlooked even as the world loses morale and weakens measures against the disease, he said, adding that it only posed a greater challenge for China to keep imported cases under check.

Globally, the confirmed cases increased by 55 percent in the week of January 3 to 9, with over 15 million new cases and over 43,000 new deaths in just one week, according to the WHO's weekly report.

The seemingly milder symptoms of Omicron led people to lower their guards and a rapid surge of cases was seen across the globe, with the U.S. topping the charts for daily cases.

More than 800,000 new infections are being reported each day according to the New York Time's tally, and that number could be an undercount of actual infections given that more people are testing themselves at home and not reporting results to healthcare providers.

Omicron is responsible for more than 98 percent of COVID-19 cases in the U.S., replacing Delta in less than a month, according to the U.S. Center for Disease Control and Prevention.

The country is also seeing a 50-percent increase in deaths and a record-breaking hospitalization rate for coronavirus patients straining its healthcare system.

Even so, the U.S. health authorities, including the U.S. Food and Drug Administration Commissioner Dr. Janet Woodcock and U.S. top infectious disease expert Dr. Anthony Fauci are telling people to expect getting infected eventually.

"I think in many respects, Omicron, with its extraordinary, unprecedented degree of efficiency of transmissibility, will ultimately find just about everybody," Fauci said during a virtual chat last Tuesday with the Center for Strategic and International Studies Commission.

With Omicron's high transmissibility and immune escape capability, current vaccines developed are targeting severe illness and deaths prevention instead of preventing contracting the virus.

In a country with more than 200 million people being fully vaccinated, the current observed case-fatality ratio is reportedly 1.3 percent, according to data by the New York Times and Johns Hopkins University, whereas the infection fatality rate of seasonal flu is 0.1 percent.

"That is to say, you can't really ignore it," Zhang said, discussing the lethality of Omicron. "And if you really do nothing, it will bring very serious consequences."

Read more: Too soon to treat COVID-19 like flu as Omicron spreads: WHO

Is a fourth booster needed?

"Not urgently needed" is Zhang's perspective for Chinese residents, but a third booster shot can indeed increase one's neutralizing antibody level by at least 10 folds as more international data has indicated.

A recent research showed that a protein-based COVID-19 vaccine developed by China's vaccine maker Sinopharm can elicit stronger antibody response against Omicron when given as a booster.

As for the requirement of a fourth booster dose from a global viewpoint, experts have mixed views.

Israel has rolled out fourth COVID-19 vaccine dose for people over 60 and medical staff, and its study suggested that a fourth dose of COVID-19 vaccine boosts antibodies by five folds a week after the shot is administered.

A European Union's drug regulator expressed doubt on it last week. Marco Cavaleri, head of vaccines strategy at the European Medicines Agency, said in a media briefing that repeated vaccination within short intervals is not a sustainable long-term plan.

With the case number from China being small thanks to effective containment measures, Zhang expects more data from abroad for analysis.

"People with low immunity and advanced age may get the fourth dose, but there is no need to worry about it now, and we can have more international experience for us at that time."