U.S. President Donald Trump has said he disagrees with the assessment of the country's top immunologist, Anthony Fauci, on the dire situation the United States faces as cases of the novel coronavirus continue to spread.

President Donald Trump has formally started the withdrawal of the United States from the World Health Organization, making good on threats to deprive the U.N. body of its top funding source over its response to the coronavirus.

Brazilian President Jair Bolsonaro tested positive for the new coronavirus Tuesday after consistently downplaying the risks of the disease, as the World Health Organization acknowledged "emerging evidence" of airborne transmission.

A coronavirus outbreak among Rohingya refugees has been "successfully contained", Bangladesh officials have said after fears that the disease spread rapidly in overcrowded camps.

Iran announced on Tuesday 200 more deaths from the coronavirus, the most in a single day since the Middle East's deadliest outbreak began in February.

Beijing on Tuesday reported zero new coronavirus cases for the first time since the emergence of a cluster in the Chinese capital in June that prompted fears of a domestic second wave.

A total of 335 people have been infected since a cluster emerged at the city's massive Xinfadi wholesale market in early June.

More than five million residents of Melbourne will be locked down for six weeks after coronavirus cases surged in Australia's second-biggest city, authorities announced Tuesday.

The United States passed another grim coronavirus milestone Monday as the death toll from the virus climbed past 130,000, according to a tally kept by Johns Hopkins University.

An international group of 239 scientists on Monday urged authorities including the World Health Organization to recognize that the coronavirus can spread in the air at distances well beyond two meters (six feet), and to revise their prevention guidelines accordingly.

The pharmaceutical firm Regeneron on Monday announced it was entering the late stages of its human clinical trials investigating a drug to both treat and prevent COVID-19.