The United States kicked off a mass vaccination drive Monday hoping to turn the tide on the world's biggest coronavirus outbreak, as the nation's death toll passed a staggering 300,000.
The start of the desperately awaited vaccine program coincided with several European countries announcing new lockdowns amid spiralling infections, highlighting the long road to ending the global pandemic.
New York nurse Sandra Lindsay became the first person in America to receive the Pfizer-BioNTech shot, live on television, six days after Britain launched the West's vaccine campaign against Covid-19.
"It didn't feel any different from taking any other vaccine," said Lindsay, a critical care nurse at the Long Island Jewish Medical Center, imploring all Americans to "do our part" by getting vaccinated.
"I hope this marks the beginning of the end of the very painful time in our history," she added.
The vaccinations come at one of the darkest phases of the pandemic, with cases in the US and many other countries soaring, and health experts struggling against vaccine scepticism, lockdown fatigue and uneven adherence to safety rules.
On Monday, the Netherlands prepared to enter its strictest lockdown since the pandemic began, Britain announced new restrictions on London, and Turkey said it would go into a four-day lockdown over the New Year holidays.
From Tuesday, people in France will no longer need to fill out forms justifying their reason for leaving home, but will instead be subject to a new 8:00 pm-6:00 am curfew.
The US -- which has the globe's highest death toll, and the largest number of reported cases at 16.3 million -- passed 300,000 deaths just hours after vaccinations began.
"First Vaccine Administered. Congratulations USA! Congratulations WORLD!" President Donald Trump wrote on Twitter earlier in the day, while President-elect Joe Biden tweeted "Stay hopeful - brighter days ahead."
Vaccinations also took place in California, Pennsylvania and Ohio, while Canada administered its first dose to a caregiver in Montreal.
London lockdown
An initial 2.9 million doses are set to be delivered to 636 sites around the country by Wednesday, with officials saying 20 million Americans could receive the two-shot regimen by year end, and 100 million by March.
Doses are being shipped in boxes containing dry ice that can keep supplies at -70 degrees Celsius (-94 degrees Fahrenheit), the temperature needed to preserve the Pfizer-BioNTech drug.
Trials have shown the vaccine to be 95 percent effective.
But experts face a battle to convince enough Americans to take it to make it effective in a country where the anti-vaccine movement is strong.
"My biggest concern is the level of hesitancy in the country. I really hope we are going to be able to change that," Moncef Slaoui, head of the government's vaccine rollout program Operation Warp Speed, told CBS.
Worldwide, there have been at least 1.6 million deaths since the outbreak emerged in China last December, and 71.6 million cases overall.
Also launching vaccinations Monday was the United Arab Emirates which began administering shots by Chinese drugs giant Sinopharm in Abu Dhabi.
New strain
Britain's health minister announced that London will move into the highest level of restrictions from Wednesday with theatres, pubs and restaurants forced to close except for takeaway food.
Matt Hancock said scientists had identified a "new variant" of the virus in the south of England that may be causing infections to spread faster, though he added it was "highly unlikely to fail to respond to a vaccine."
Dutch Prime Minister Mark Rutte said schools and all non-essential shops would shut from Tuesday for five weeks over Christmas, while Turkish President Recep Tayyip Erdogan announced a nationwide curfew from December 31 to January 4.
Germany, which will enter a partial lockdown Wednesday with non-essential shops and schools closed, is pressuring EU authorities to speed up approval of a vaccine to match the mass inoculations in the US and Britain, according to local media.
Despite the start of the US vaccine program, internet giant Google confirmed it would not require workers to return to the office until at least September 2021, and health officials cautioned people not to grow lax.
"It's going to take months before the vaccine hits critical mass. So, this is the light at the end of the tunnel, but it's a long tunnel," said Governor Andrew Cuomo of New York state, where 35,000 people have succumbed to Covid-19.