"Instead of growing up a virus in a 50,000-litre drum and inactivating it, we could deliver RNA and our bodies make the protein, which starts the immune response", said Penn's Dr Drew Weissman.
Justin Trudeau says Canada has signed an agreement with Pfizer to receive up to 249,000 doses of its vaccine, developed with partner BioNTech, by the end of the year. In trials, the vaccine was shown to have around 95% efficacy.
"I don't think we envision any countries creating a mandate for vaccination".
"But now, vaccines are coming", Trudeau said on Monday.
The excitement in Britain, which has Europe's highest virus-related death toll at more than 61,000, was palpable.
He also said he expects the supply of vaccines to arrive in a steady stream, rather than all at once.
That, in turn, could mean that the province will be unable to conduct a large-scale vaccination of long-term care residents and will have to focus its early efforts on the staff that work in those facilities instead.
Intergovernmental Affairs Minister Dominic LeBlanc told CBC News in an interview that aired Sunday that the government wants to start discussions on health transfers, while keeping the focus on COVID-19.
Britain to start vaccination against COVID-19 by 14 December
General Practitioners, GPs, in England have been told to be ready to start giving the vaccine against COVID-19 by 14 December. The scale of the operation was laid bare last night and described as "one of the greatest challenges the NHS has ever faced".
"We've rehearsed", said the medicines and healthcare regulatory agency CEO June Raine.
In the past month, 74 people with COVID-19 were hospitalized.
The Scottish Government has received 65,000 doses of the Pfizer jab so far, with more on the way. This could take up to a day.
How will states decide which vaccines go where?Hospitals treated six COVID-19 patients in September, and 14 in October.
Then, each box must be unpacked manually and the temperature downloaded to check if it hasn't changed in transit. Such scheduling should allow claimants to still receive damages in the very unlikely event that they suffer serious side effects from the vaccine.
Pfizer's vaccine involves a two-dose regimen, administered 21 days apart, and necessitates careful handling with its sub-freezing storage requirements at minus 70 degrees Celsius.
If everyone in the United Kingdom was to be inoculated, with the population standing at about 68 million, 136 million doses would be required. The fridges, which are not portable, each hold around 86,000 doses.
Both Hancock and Prime Minister Boris Johnson say they are willing to take the vaccine in public, although the government says ministers will not jump the age-based queue.
The vaccine won't just be provided by hospitals.
The NHS hopes authorities will soon approve a safe way of splitting up the dose packs so the shots can get to nursing homes during December.