The coronavirus remains active on human skin for nine hours, Japanese researchers have found, in a discovery they said showed the need for frequent hand washing to combat the Covid-19 pandemic.

Israel started cautiously emerging from a second coronavirus lockdown Sunday after a month of tight restrictions, re-opening preschools, kindergartens, beaches and national parks, with numbers of new infections falling.

The number of people in South Africa who have tested positive for coronavirus has topped 700,000, official figures showed overnight, another grim milestone for the continent's worst-hit country.

Millions of French people enjoyed a last night of freedom on Friday before a Covid-19 curfew in Paris and other large cities came into force at midnight, for a least a month, prompted by an alarming surge in new cases.

The antiviral drug remdesivir, considered one of the most promising Covid-19 treatments, turns out to do little to prevent deaths from the disease, according to a WHO-backed study.

Remdesivir, which was part of the experimental cocktail given to US President Donald Trump when he caught the new coronavirus last month, was one of several reviewed in a large study of more than 11,000 people across 30 countries.

A $60 double-dose experimental coronavirus vaccine is being made available to some residents in an eastern Chinese city, health officials have said, the first details of a mass rollout for an as-yet unproven vaccine.

More than half of countries in the EU, plus the UK, were on Thursday labelled red in a new map issued by the bloc's disease control agency aimed at guiding decisions on travel restrictions.

The World Health Organization's European office said Thursday that the soaring number of Covid-19 cases in Europe has caused "great concern", but said the situation was still better than the peaks in April.

Almost 10 million people in the Chinese city of Qingdao have now been screened for the coronavirus, officials said Thursday, as authorities rushed to quash an outbreak through an ambitious programme of mass testing.

France on Wednesday became the latest European country to toughen anti-coronavirus measures, imposing a curfew in Paris and eight other cities from Saturday, while Germany and Ireland also ramped up restrictions. 

"We have to act. We need to put a brake on the spread of the virus," President Emmanuel Macron told public television, announcing a shutdown between 9:00 pm and 6:00 am that will remain in force for as long as six weeks.