Coronavirus could infect 60% of the world's population if it is left 'unchecked,' a leading disease expert warned

• Current rates of coronavirus infection suggest that 60-80% of the global population could potentially get the virus if it is not brought under control, reports The Guardian.
• Dr Gabriel Leung told the paper that experts must assess how well Chinese containment efforts have worked so far, in case other countries should be replicating those measures.
• His comments come as the World Health Organization (WHO) starts a two-day meeting to accelerate scientific understanding and the global response to the viral outbreak.
• The WHO director Dr Tedros Adhanom Ghebreyesus tweeted on Sunday that the relatively small number of cases outside of China may yet be "the tip of the iceberg."
• Visit Business Insider's homepage for more stories.

A leading epidemiologist has suggested that without effective control, the coronavirus could infect between 60% of the world's population due to its current estimated "attack rate," if it is left "unchecked."

"60% of the world's population is an awfully big number," Dr Gabriel Leung told The Guardian's Sarah Boseley.

The paper reports that it is based on the rate at which infected people are passing the virus on - which experts believe currently stands at 2.5 people per sufferer, according to Reuters.

Dr Leung, a SARS expert who also managed Hong Kong's response to the swine flu outbreak of 2009, spoke to The Guardian en route to a global research forum currently being convened by the World Health Organisation (WHO) in response to the coronavirus crisis.

His priority at the WHO meeting will be to call for an urgent assessment of which of containment measures trialed in China have actually worked - and, if necessary, to impose them in other affected countries.

His comments come after the WHO director Dr Tedros Adhanom Ghebreyesus said that infection rates outside of China could "accelerate" and be "the tip of the iceberg."

In an opinion piece for The New York Times, Dr Leung outlined the questions that the epidemiologists, public health experts, politicians and health research funders will bring to the WHO meeting.

"In magnitude, scale and velocity, this coronavirus, known as 2019-nCoV, is too big a problem for any one team to solve," he wrote. The death toll from the virus topped 1,000 people on Monday, Chinese authorities said.

He added: "We need to get a clear view of the contagion and plug the holes in our understanding of the disease to inform public health decisions that affect hundreds of millions of lives."

Doctors at the London School of Hygiene and Tropical Medicine have estimated that the virus will peak in mid-February, by which pointit is set to infect around 500,000 people in the city of Wuhan where it originated.

In his NYT op-ed, Dr Leung pointed out that scientists must now get a handle on the "clinical iceberg," that is, what number of cases are going undetected.

Some only get mild symptoms of the coronavirus or go without symptoms at all for up to two weeks.

"Out of view is some proportion of mildly infected people, with minor symptoms or no symptoms, who no one knows are infected," he wrote.

However, he warned that calculating this with such a fast-moving situation is not as simple as it sounds. Mysteries remain for scientists at the WHO meeting to look at.

"The challenge involves trying to quantify how many infections were actually prevented through measures such as wearing masks, closing schools and locking down cities," he wrote.

In an earlier report for The Lancet on January 31, Dr Leung and colleagues wrote that authorities should be prepared to impose "substantial" and "immediate" public health measures to prevent "self-sustaining outbreaks" of the virus in major cities outside of China.