With the rollout of vaccines around the world, many of us are beginning to believe the end is in sight for the nightmare that has been the Covid-19 pandemic.
But, while steps are being taken around the world that will ultimately restore some sense of normality, a key question remains unanswered.
How long will it take before life is back to how it was before? A life that didn't involve masks, social distancing, being told to sit down at pubs, and Zoom parties.
While there are likely to be unseen events that could bolster or hinder the path towards pre-pandemic life, new calculations predict roughly when that could be.
Bloomberg has built the biggest database of Covid-19 vaccines given around the world and, by their calculations, it will take seven years.
Number-crunchers at the publication say it will take that long to reach leading US doctor Anthony Fauci's estimate for the herd immunity threshold of 75 per cent of people inoculated globally.
Vaccination numbers already fluctuate wildly from country to country, and some nations are expected to hit that threshold much more quickly.
While we haven't started the process here in New Zealand, some nations, like Israel for example, may hit the threshold fairly soon.
The middle-eastern nation is on track to see 75 per cent coverage by autumn but it could take Portugal four years, China seven years and Latvia almost nine years to reach herd immunity if vaccine distributions don't change. The US is predicted to reach herd immunity just in time for New Year's 2022.
The rate of vaccination likely to change, but there are also likely to be disruptions — such as supply issues and whether the vaccines are effective against variants like those that emerged in South Africa and Brazil.
Bloomberg's experts explained the calculations were "volatile" — with the global vaccine rollout already being marred by supply disruptions. Those disruptions have come with only a third of the world's countries starting vaccine campaigns.
However, the publication noted the pace of vaccination is expected to accelerate worldwide as more and more jabs become available — they pointed to major vaccine-manufacturing hubs in India and Mexico, and said production is just getting started.
Bloomberg's calculator is based on two doses for full vaccination and will be tweaked once the vaccine made by Johnson & Johnson, which only requires one dose, is made available. While the vaccines haven't been approved for children, Bloomberg included them in their calculation because they too can be infected, and transmit, the virus.
The calculations also don't account for any level of natural immunity experienced by those who've previously had the virus — experts believe some immunity is offered after an infection but it is not yet clear on how long it lasts.
Adding to the uncertainty is the disparity between developing and developed nations in terms of accessing and rolling out the vaccines.
It's important to look at the global picture because the pandemic is a global event by definition, so if a country doesn't reach herd immunity the virus could take hold there as well as be exported to other nations, risking an international resurgence.
Concerned by what is happening so far, the World Health Organisation overnight issued a demand to vaccine makers to dramatically boost production.
WHO chief Tedros Adhanom Ghebreyesus told reporters that while the number of Covid-19 vaccines administered (115 million) had now overtaken the number of infections worldwide (104 million), more than three-quarters of the jabs had been handed out in just 10 wealthy countries.
"Almost 130 countries, with 2.5 billion people, are yet to administer a single dose", Tedros complained.
"Unless we suppress the virus everywhere, we could end up back at square one," the WHO chief said, calling on vaccine manufacturers to implement "a massive scale-up in production."
Even in developed regions like Europe — the worst-affected region in the world — there are problems.
There have been 760,000 deaths linked to the virus in Europe. The slow vaccine rollout has sparked public anger and plunged the bloc's leadership into crisis.
EU member states needed to work more closely with drug firms to increase the pace of inoculation, the WHO's regional chief said.
"We need to join up to speed up vaccinations," the WHO's Europe director Hans Kluge told AFP in an interview.
"Otherwise, competing pharmaceutical companies (must) join efforts to drastically increase production capacity … that's what we need." Despite the troubled start to the vaccine rollout in the 27-nation bloc, German Chancellor Angela Merkel and French President Emmanuel Macron defended Brussels' strategy.
"I fully support the European approach," Macron told an online news conference after talks with Merkel. "What would people say if countries like France and Germany were competing with each other on vaccines?" "It would be a mess, and counter-productive," he said.
- with agencies