Renowned Chinese respiratory specialist Zhong Nanshan said that there is no evidence showing that COVID-19 originated in Wuhan, noting that it is irresponsible to jump to conclusions without getting facts straight.

Zhong Nanshan (Photo: CGTN)

Zhong made the remarks at a press conference in Guangzhou on Wednesday, stressing that so far there is no targeted therapeutic COVID-19 drug and international cooperation is still needed for new experiments.

The fight against the COVID-19 should not be reliant on "herd immunity," Zhong added, saying that the production of an effective COVID-19 vaccine is at present the top priority, and the development requires international cooperation.

Last week, UK Chief Scientific adviser Sir Patrick Vallance recommended that 60 percent of British population to be infected with COVID-19 to get herd immunity for the disease, which provoked controversy around the world.

Herd immunity, also known as community immunity, occurs when a sufficient portion of a population is immune to a specific disease (usually through vaccination and/or prior illness), so that it can make the spread from person to person unlikely.

According to this theory, the greater the proportion of a population that is immune or less susceptible to a disease, the lower the probability that a susceptible person will come in contact with an infected person.

"There is no evidence of immunity for life after one infection of the virus," Zhong added.