Coronavirus could kill 45m warns top Hong Kong medical official

Covid-19, the name given to the novel coronavirus, could kill 45 million people worldwide and infect 60 per cent of the global population if it can't be contained, a leading expert has warned.

Professor Gabriel Leung, chair of public health medicine in Hong Kong, made the comments while en route to a meeting of the World Health Organisation.

He warned that an "attack rate" of 60-80 per cent meant that even if the fatality rate was as low as 1 per cent, the death toll would be staggering.

People wearing protective suits stand near an entrance at the Cheung Hong Estate, a public housing estate, during evacuation of residents in Hong Kong. Photo / AP

Leung told The Guardian that recent cases of infections in people who had never visited China could be the "tip of the iceberg" and said "60 per cent of the world's population is an awfully big number".

"Is 60-80 per cent of the world's population going to get infected? Maybe not. Maybe this will come in waves. Maybe the virus is going to attenuate its lethality because it certainly doesn't help it if it kills everybody in its path, because it will get killed as well," he said.

Epidemiologist Professor Leung is one of the world's leading experts on coronavirus outbreaks and played a leading role in the Sars outbreak.

He earlier warned that outbreaks were likely to be "growing exponentially" in China, writing in The Lancet that "independent self-sustaining outbreaks in major cities globally could become inevitable" because of the movement of people who were asymptomatic.

Leung stressed that containment was essential and that if anyone within a quarantine facility tested positive, a 14-day period should be restarted for everyone inside.