THE first volunteers to get the Pfizer coronavirus vaccine have said they felt like they had a "severe hangover" after the injection.
Some of the 43,500 people to get the Covid-19 jab have compared its side effects to those of the flu vaccine, including headaches and sore muscles.
⚠️ Read our coronavirus live blog for the latest news & updates
It comes after Pfizer revealed findings from its major clincal trial suggest the jab was more than 90 per cent effective in preventing the killer bug.
Trial volunteer Glenn Deshields, 44, from Austin, Texas, compared the side effects to "a severe hangover" but said symptoms quickly cleared-up.
Another volunteer, 45-year-old Carrie from Missouri, said she experienced a headache, fever and body aches, after her first shot in September.
The side effects - which she compared to those from the flu jab - were worse after having her second dose last month, she said.
REAL DEAL
As the trial is double blind, the participants do not know if they are receiving the vaccine or a placebo.
But Carrie, who works in publishing, believes she was given the Covid jab, due to the side effects she experienced.
Mr Deshields also reckons he got the real McCoy after suffering hangover-like symptoms after his injection.
He subsequently scheduled an antibody test through his doctor and it came back positive, so he was confident he had not received the placebo.
He said his own immune reaction to the shot made him confident about the vaccine, but he was nevertheless "very excited" by Monday's news.
He added: "My grandfather, one of his first memories was of the bells ringing when World War I ended.
"It was a horrific war and horrible things happened and people were just happy it was over with.
"In my mind I felt the same way... I kind of felt it was something like that. Thank god, it's going to be over at some point."
Bryan, an engineer from Rome, Georgia, said he felt "a little bit of pride" on hearing the news but added that taking part in the study was "the least I could do to help out" as "a lot of people are needlessly suffering from the virus" in America.
He believes he was given the placebo - he felt no immune response and, having received his two shots, came down with Covid shortly after his daughter caught it last month.
The 42-year-old's whole family ultimately caught it but have all recovered.
MAJOR BREAKTHROUGH
Pfizer and its vaccine partner BioNTech announced on Monday that their coronavirus vaccine was more than 90 per cent effective in protecting people from Sars-CoV-2, the virus that causes Covid-19.
Brits are expected to be among the first in the world to receive the vaccine, Health Secretary Matt Hancock today revealed.
The UK's medicines regulator could approve the jab within days of a licence application being submitted due to rolling analysis of the data, he said.
Mr Hancock said the military and NHS staff are on standby to roll out a vaccine from the start of December and will work "seven days a week", with GPs, new vaccination centres and pharmacists all playing a role.
But there are many hurdles to overcome before the "vast task" of vaccination could begin, he warned.
This includes getting regulatory approval of the new Pfizer/BioNTech vaccine and assessment of its safety data.
Once it gets the green light, the elderly and health and care staff will be first in line, though most other people will not get a jab until 2021.
Asked whether a vaccine could be available by Christmas, Mr Hancock said that was "absolutely a possibility", adding that vaccination clinics would be open on bank holidays and weekends.
Data on the jab from Oxford University and AstraZeneca is just weeks away, with Sir John Bell, who is part of the Oxford team, saying he expects two or three jabs to be available by the new year.
Mr Hancock said the UK's Medicines and Healthcare products Regulatory Agency (MHRA) has been working closely with both Pfizer and AstraZeneca, gathering information as clinical trials progress.
He told BBC Radio 4's Today programme: "The MHRA, which is one of the best medical regulators in the world, they've been working closely with the companies - with Pfizer and AstraZeneca - so that they've been looking at the data all the way through in what's called a rolling review.
"(This is) rather than waiting, as is normal, for the end of the process, for all the data to be then handed over for them to start looking at it.
"So that means that the regulator will be able to make a judgment on whether this is clinically safe, and not just take the company's word for it, but do that within a matter of days from a formal licence application."
Mr Hancock said Oxford's vaccine was easier to deploy than Pfizer's, which needs to be kept at a temperature of minus 70C.
Pfizer's jab is also being manufactured in Belgium, he said, but a lot of work had been carried out to deploy vaccines as soon as they become available.
"We'll be among the first countries in the world to be able to start to do this," he said.
Most read in Health News
Earlier, Mr Hancock said experts needed to see Pfizer's full safety data and he would not approve a vaccine until it had undergone all its safety checks.
READ MORE SUN STORIES
The Health Secretary said that once a vaccine becomes available, it will be delivered through care homes, GPs and pharmacists, as well as "go-to" vaccination centres set up in venues such as sports halls.
There are currently more than 200 coronavirus vaccine candidates being tested around the world, 40 of which are currently undergoing clinical trials.