Britain on Tuesday became the first Western country to start a mass coronavirus vaccination campaign, with a 90-year-old woman receiving the initial jab as more positive developments were announced for vaccines against the pandemic.

Kicking off Britain's "V-Day", Margaret Keenan said she felt "privileged" to be given the injection, the first of millions expected to be administered in the hard-hit country over the coming months.

Covid-19 vaccine
Britain has started the first rollout of the Pfizer-BioNTech coronavirus vaccine Photo: POOL / Dominic Lipinski

The Pfizer-BioNTech jab is one of several vaccines bringing hope for an end to the pandemic that has killed more than 1.5 million people worldwide and ravaged economies.

Frontrunners Pfizer-BioNTech and US biotech firm Moderna have reported efficacy of 95 percent and 94 percent respectively and have given data to regulators.

But Oxford University and AstraZeneca became the first Covid-19 vaccine makers to publish final-stage clinical trial data in a scientific journal.

Covid-19 vaccine
Margaret Keenan, 90, became the first person to get the newly approved coronavirus vaccine as Britain began its innoculation roll-out Photo: POOL / Jacob King

The study, published in the respected Lancet medical journal, confirmed that their vaccine works in an average of 70 percent of cases.

But the focus remained on the launch of the Pfizer-BioNTech jab.

The UK's second jab went to a man named William Shakespeare.

The over-80s, care home workers, and at-risk health and social care staff will be at the front of the line for vaccination.

Almost 40 percent of the new cases detected over the last seven days worldwide have been in Europe, the region topping 20 million cases on Tuesday. But the rate of infection appears to be stabilising.

California lockdown
The extent of the crisis in the US is illustrated by the lockdown in California, the most populous American state, where authorities forced most offices to close and banned gatherings among different households. Photo: AFP / Frederic J. BROWN

Russia, one of Europe's hardest-hit countries in terms of cases, on Saturday began vaccinating high-risk workers with its own jab, Sputnik V, and Beijing has also begun an emergency inoculation campaign with a medicine made in China.

The United States is expected to grant emergency authorisation for the Pfizer-BioNTech vaccine later this week, announcing on Tuesday that no concerns had been found in trial data.

Despite the vaccination news, virus restrictions continue to be reimposed -- roughly 30 million people in the US state of California are now under stay-at-home orders.

Covid-19 vaccine
Graphic on what it would take to vaccinate the world to end the Covid-19 pandemic. Photo: AFP / John SAEKI

And the World Health Organization has warned that successful vaccines on their own will not immediately end the crisis.

Covid-19 vaccine
A patient with COVID-19 symptoms is transported on a trolley at IMSS Hospital General #1 in Tijuana, Baja California State, Mexico Photo: AFP / Guillermo ARIAS

US President Donald Trump signed an executive order "to ensure that American citizens have first priority to receive American vaccines."

But he faces questions over whether the White House missed an opportunity to shore up sufficient doses in the months ahead.

Covid-19 vaccine
A child kisses volunteer Fatima Sanson, dressed up as Mrs. Claus, in Belo Horizonte, Minas Gerais state, Brazil Photo: AFP / DOUGLAS MAGNO

President-elect Joe Biden warned meanwhile that coronavirus vaccination efforts in the United States will "slow and stall" if Congress does not urgently come up with funding.

America's floundering efforts to quell the pandemic have been widely criticised -- the nation is the world's worst-hit with more than 283,000 deaths.

California ordered most offices to close and banned gatherings among different households.

Bars and services such as hair salons were shut and restaurants were allowed to serve takeaway only. Non-essential travel was also temporarily restricted statewide as California experienced record new Covid-19 cases.

"The overwhelming majority of Californians are now in this new stay-at-home order protocol," said state Governor Gavin Newsom, who earlier warned that the state hospital system risked being overwhelmed.

The US Food and Drug Administration on Tuesday said data from trials of Pfizer-BioNTech drug revealed "no specific safety concerns".

The data "suggest a favourable safety profile, with no specific safety concerns identified that would preclude issuance of an EUA (emergency use authorisation)", it said.

The FDA is also expected to give the green light to the Moderna vaccine.

Canadian Prime Minister Justin Trudeau said Pfizer and BioNTech will deliver their first doses to his nation within weeks.

In India, two pharmaceutical firms -- including Serum Institute, the world's biggest manufacturer of vaccines -- on Monday sought fast-track approval for coronavirus shots.

India is the second-worst hit nation having already recorded more than 140,000 deaths.

And in Brazil's Sao Paulo state -- Latin America's coronavirus epicentre -- authorities will launch a campaign from January providing the Chinese-developed vaccine CoronaVac to healthcare workers, older people and other vulnerable groups first.

Even as hopes rise for vaccines and a resulting economic recovery, governments are being forced to tighten restrictions to contain surges in infections.

German Chancellor Angela Merkel urged regions with high coronavirus rates to tighten curbs, while Denmark said it will close middle and high schools, bars, cafes and restaurants in half of the country.

But Austrians got a boost when the government lifted its measures earlier this week.

"We couldn't wait with the shopping, even if it might be a bit crowded today," Robert Bauer told AFP as he shopped in Vienna.

Israel has announced a nationwide night-time curfew from December 9 following a steep increase in virus cases. And Hong Kong announced a ban on evening dining at restaurants and the closure of fitness centres to contain a new wave of cases.

Copyright AFP. All rights reserved.