Germany has banned gatherings of more than two people in public at a time just as Chancellor Angela Merkel went into quarantine because of her recent contact with a doctor who had tested positive for coronavirus.
Ms Merkel's spokesman said the German chancellor, who is 65, was informed about the doctor's test shortly after holding a news conference yesterday announcing new measures to curb the spread of the virus.
For at least the next two weeks, people will not be allowed to form groups of more than two in public unless they live together in the same household or the gathering is work-related.
As part of a bundle of stricter rules, restaurants can only offer takeaway services and hairdressers and beauty, massage and tattoo parlours must close.
Ms Merkel's spokesman Steffen Seibert said she had gone to the affected doctor for a precautionary vaccine against pneumococcal infection.
Meanwhile, Italy has banned travel within the country in yet another attempt to slow the spread of Covid-19. New data yesterday showed a further 651 people had died from the disease, lifting the number of fatalities to 5,476.
The interior and health ministries have now warned people they have to stay where they are, unless urgent business or health reasons forced them to move to another town or region.
A month after the first death from the highly infectious virus was registered in Italy, the government also issued an order freezing all business activity deemed non-essential in an effort to keep ever more people at home and off the streets.
Among the sectors targeted were the car, clothing and furniture industries.
Italy has registered more deaths than any other country in the world, while the number of confirmed cases is second only to China, with the tally rising by 5,560 to 59,138.
However, offering a ray of hope, the latest figures represented an improvement on Saturday, when the death toll rose by 793 and new cases increased by 6,557.
The number of deaths in Spain rose by nearly 400 in its largest one-day jump to date. More than 1,700 people diagnosed with the coronavirus have now died in Europe's second worst-hit country.
France - where the death toll stood at 562 on Saturday - reported its first known death of a doctor from coronavirus.
In Britain, Boris Johnson has threatened a total lockdown within 24 hours amid growing concern at the failure of the public to heed demands for 'social distancing' to prevent the coronavirus spreading.
He said the UK could follow France, Italy and Spain, where people's movements have been restricted by police, curfews have been imposed, parks closed and all stores except food shops and pharmacies shut.
His comments came after a weekend in which thousands of people spurned the government's "stay home" advice to take advantage of weekend sunshine to crowd towns and parks and go shopping.
Mr Johnson said: "I don't think you need to use your imagination very much to see where we might have to go, and we will think about this very, very actively in the next 24 hours.
"We need to think about the kind of measures we've seen elsewhere - other countries that have been forced to bring in restrictions on people's movements altogether."
It came as Mr Johnson also announced 1.5 million people with underlying health conditions and at the highest risk from the coronavirus would be asked to stay at home for at least the next three months, with medicines and pre-ordered food parcels delivered to their doorstep.
The UK death toll rose yesterday by 48 in just 24 hours to 281, with 665 new cases pushing the total confirmed to more than 5,600. Those who died included an 18-year-old, Britain's youngest victim.
Worldwide, more than 316,000 people have been infected and nearly 13,600 have died.