Health authorities have reported a spike in new coronavirus cases in Germany, the Netherlands, Sweden, Ukraine, Greece and India.
Germany is in a third wave of the coronavirus pandemic, Chancellor Angela Merkel told MPs in her conservative party, two sources at the meeting told Reuters on Tuesday.
"We are now in the third wave," they quoted her as saying and said she warned that any easing of lockdown measures introduced late last year and extended until March 7 would have to be done carefully and gradually.
Confirmed coronavirus infections in the Netherlands rose by nearly 19 per cent over the past week as more people got tested following a week of icy conditions, the country's public health institute said on Tuesday.
The percentage of positive tests in what the institute called a "third wave" of infections declined slightly from 11.5 per cent to 9.8 per cent.
"Because the majority of the population has not yet been vaccinated, it is very important to prevent infections as much as possible and to keep this third wave as low as possible," the institute said.
"This is only possible if a relaxation (of the lockdown) is done with great caution and step-by-step."
Meanwhile, authorities in Sweden's capital of Stockholm urged people to use face masks when on public transportation, shops and workplaces.
"We want people to use face masks in public transport around the clock, especially during rush hour," the city's infection control doctor Maria Rotzen Ostlund said.
Stockholm has had a 27 per cent infection increase in recent weeks.
Swedish chief epidemiologist Anders Tegnell said Sweden "unfortunately is seeing an upswing again," adding the variant first reported in the UK "has increased at a very fast pace".
Sweden has reported 12,713 confirmed deaths and a total infection number of 642,099, an increase of 10,933 cases since Friday.
The number of cases in western Ukraine has risen sharply since the end of a strict two-week lockdown last month, officials said.
In the city of Ivano-Frankivsk, the Emergencies Ministry put up a hospital of 10 tents with 120 beds in case of an sudden influx of patients.
The rise in infections has put doctors under severe strain.
Viktor Boyko, the chief of the hospital in the western city of Kolomyya said there aren't enough doctors to help the ill, while physicians are "burning out" amid all the suffering of patients they can't treat.
"Vaccination should help, we are glad that the vaccine is coming and soon we will have a reliable shield against this disease," Boyko said.
Greek health authorities also noted a spike in new coronavirus cases, about half of which were in the greater Athens region.
A total 2147 new infections were recorded on Tuesday, up from 880 a day earlier despite the ongoing lockdown, bringing the total to more than 180,000.
Authorities also recorded 22 new deaths on Tuesday, raising the total to 6343 confirmed deaths.
Indian officials said on Tuesday that mutated versions of coronavirus were not responsible for an upsurge in cases in two states.
Maharashtra in the west and Kerala in the south account for 75 per cent of India's current active cases of about 147,000 and both states have registered a sudden rise in new infections in recent days.
A top government health official confirmed the long-time presence of two mutants - N440K and E484Q - in those two states as well as elsewhere in the country and abroad.
Authorities have also found the UK variant in 187 people in India, the South African one in six and one case of the Brazilian mutation.
"There is no reason today for us to believe, on the basis of scientific information, that these are responsible for the upsurge of the outbreak," Vinod Kumar Paul, who heads a government committee on vaccines, told a news conference.
"We are constantly watching the behaviour of mutations in our country."
Though cases have come down sharply since a September peak, Paul said India was still vulnerable, especially given that even previously badly affected cities like Pune in Maharashtra were getting hit again.
He urged people to wear masks and avoid social events.
India has reported more than 11 million cases - the most in the world after the United States - and about 156,000 deaths.
Australian Associated Press
