As the year drew to a close, the emergence of the Omicron variant pushed the number of daily new Covid-19 cases past one million for the first time, according to an AFP tally.
France became the latest country to announce Omicron was now its dominant coronavirus strain on Friday. In Britain, the United States, and even Australia -- long a refuge from the pandemic -- the variant's prominence is driving record new cases.
To party, or not?
Parts of the Pacific nation of Kiribati became the first to welcome in the new year from 1000 GMT.
But from Seoul to San Francisco, celebrations have again been cancelled or curtailed as infections rise.
In Sydney, which in normal times bills itself as the "New Year's Eve capital of the world", the vast harbour where people gathered to watch the city's famous fireworks was notably uncrowded.
With tourists still unable to enter the country and many residents fearful of the rapid spread of Omicron, tens of thousands were estimated to have attended, rather than the one million-plus who normally flock to the foreshore.
Still, the city saw New Year's Eve in with a bang -- igniting six tonnes of technicoloured fireworks that lit up the Opera House and floating barges, turning the Harbour Bridge rainbow-like.
"I'm just trying to focus on the positive things that happened this year, rather than dwelling on all the bad things that have happened," 22-year-old medical student Melinda Howard told AFP as she waited for the show.
Dubai is planning a pyrotechnics spectacle at the Burj Khalifa, the world's tallest tower, despite a slew of infections in the United Arab Emirates.
Meanwhile the northern emirate of Ras Al Khaimah will attempt to break two world records with a huge fireworks display.
In South Africa -- the first country to report Omicron back in November -- a curfew was lifted late Thursday to allow festivities to go ahead.
Health officials said that a dip in infections in the past week indicated the peak of the current wave had passed -- crucially without a significant increase in deaths.
'Only one desire'
In Rio, celebrations on Copacabana Beach will go ahead in a scaled back format -- though crowds of revellers are still expected.
"People have only one desire, to leave their homes, to celebrate life," 45-year-old Copacabana beach waiter Francisco Rodrigues said.
Some Brazilians are more circumspect, such as Roberta Assis, a 27-year-old lawyer. "It's not the moment for large gatherings," she said.
Authorities in Seoul are showing similar caution, barring spectators from a traditional midnight bell-ringing that will instead be live-streamed.
In India, fearing a repeat of a devastating virus surge that overwhelmed the country in April and May, cities and states have imposed restrictions on gatherings, with Delhi implementing a 10:00 pm curfew.
Mumbai police on Friday issued evening bans on people visiting public places such as the city's beaches and seafront promenades, normally popular sites for seeing in the new year -- with the restrictions set to last two weeks.
The World Health Organization has warned of trying times ahead, saying Omicron could lead to "a tsunami of cases".
"This... will continue to put immense pressure on exhausted health workers, and health systems on the brink of collapse," WHO chief Tedros Adhanom Ghebreyesus said.
Many Western leaders have been hesitant to reimpose strict controls seen in 2020, for fear of sparking a new economic downturn.
But on-again-off-again restrictions have still prompted frequent, vocal and occasionally violent anti-lockdown, anti-vaccine and anti-government protests.
Experts and non-experts alike hope that 2022 may be remembered as a new, less deadly phase of the pandemic."Hopefully 2022 is going to be better for everyone," said 31-year-old reveller Oscar Ramirez in Sydney.
"Everyone in the world needs a big change."