People shouldn't expect to acquire natural immunity from COVID-19 infections as there is still more to learn about the virus, an expert of China's Center for Disease Control and Prevention (CDC) warned at a press conference on Friday.

"Theoretically the immunity can be generated after the infection but it shouldn't be our choice to make at the current situation," said Wang Huaqing, chief expert on the immunization program of CDC. 

He explained the Omicron strain can still cause severe cases and deaths, especially among seniors and people with underlying diseases. He said expecting to obtain immunity from infections rather than vaccines is "a dangerous choice."

He also cited academic journal research saying uncertainty remains in immunity caused by infections as current research shows the immunity from infection could be less effective compared to immunity from vaccines. 

Full vaccination now is better than Omicron-specific vaccination later

Wang also clarified that the current priority for everyone is to complete full vaccination against COVID-19 as soon as possible, rather than waiting for a COVID-19 vaccine specifically targeting on the Omicron strain, which is, for now, the mainstream virus strain spread globally. 

"The research into a vaccine against Omicron will provide us with an extra option," Wang said. 

Although China is undergoing clinical trials of Omicron vaccines, "it still takes times to confirm its results," said Wang. 

The COVID-19 vaccines in use show significant effects in preventing severe symptoms and deaths, he added.

Could vaccination trigger other illness?

Wang also mentioned research conducted by experts from multiple fields is required to determine if the vaccination is relevant with other illnesses as there are some discussions reportedly on the internet saying people get other illnesses after having the vaccines such as leukemia.

To determine if the two things are relevant, signs of illness following vaccination is just a precondition, according to Wang.

He said the experts also need to consider if the relevance is reasonable and how significant it is. In addition, if there are more similar cases will also help for the research.

Wang stressed that whoever experiences severe discomfort after vaccination should see doctors. "We are still ... learning of the abnormal reactions to the vaccines," he said. "The relevance between vaccines and some illness must come from experts from multiple fields."

Vaccination among people over 60

As of May 26, the country has administrated 3.3 billion COVID-19 vaccine shots. About 1.29 billion people have received at least one shot and nearly 1.26 billion people are fully vaccinated, accounting for 91.47 percent, 89.07 percent separately of the population nationwide. 

About 217.6 million people aged over 60 have been fully vaccinated, making up 82.42 percent of the population aged over 60 in the country.

China reported 102 new COVID-19 cases on May 26 with most of the new infections in Beijing and Shanghai. According to a local official in Beijing, the early transmission chains of the latest resurgence in the national capital have been basically cut off. 

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