Another doctor has now come forward with claims that medics could be binning between 1,000 and 3,000 doses of the Pfizer vaccine in the UK every day.
The Pfizer vaccine is currently Britain's main vaccine programme and its rollout has come with many challenges.
The jab must be stored in -70C and once thawed, it has to be used within a matter of days.
The Pfizer vials are advertised to contain five doses but an extra one to two doses can often be obtained.
Clinics are reportedly finding it difficult to judge how many people to book in for vaccine appointments each day due to inconsistencies in their supply numbers and patient no-shows.
The reported tossing away of doses comes amid as the global demand for vaccines far outnumbers current.
The UK is aiming to vaccinate 15 million people within the next few weeks with millions of older people and key workers already having had their jabs.
The country currently has one of the highest levels of vaccine coverage, along with Israel and the UAE, but many poorer countries are yet to start any immunisations.
This week a row erupted between the UK and EU as the bloc is hit by delays to vaccine supplies.
It threatened to block Pfizer vaccine exports from Belgium to the UK after AstraZeneca told the EU it could not meet agreed supply targets up to the end of March due to vaccine production problems.
Meanwhile, the World Health Organisation is urging the UK to pause its vaccination programme once vulnerable groups have received their jabs to help ensure the global rollout is fair.
WHO spokeswoman Margaret Harris said she wanted to appeal to people in the UK, telling them “you can wait”, because ensuring equitable global distribution is “clearly morally the right thing to do”.
Prime Minister Boris Johnson has said he aims to offer all UK adults the first dose by autumn, but WHO says countries should be aiming for “two billion doses” to be “fairly distributed” around the world by the end of 2021.
WHO directors have previously said that vaccine nationalism could cost high-income countries 4.5 trillion US dollars.
Watch: COVID-19: Northern Ireland seeks UK reassurance on jabs after EU said it would block exports
Doctor claims doses being wasted
An anonymous doctor from Sussex has claimed that thousands of vaccines are likely being binned in the UK every day.
They wrote in the Independent on Saturday: “I'm a doctor and I’m writing to tell you that the news about coronavirus vaccines being binned in Britain is absolutely true.”
The doctor put this down to a combination of factors - as well as reports of some centres unexpectedly receiving extra vaccines.
They said it’s notoriously difficult to be precise about how many people to invite to a vaccine centre on any given day, which means there are often extra doses left over at the end of the day.
They wrote: “In the clinics I’ve worked at, I’ve seen between one to three doses being thrown away at the end of the day. Yes, you’ve read that correctly – vaccine doses being thrown away, when we’re in the middle of the worst national emergency since the Second World War, and these vaccines are essential in our fight against Covid-19.”
The doctor said that if this is the case across more than 1,000 vaccine centres nationally, it means between 1,000 and 3,000 doses are being “needlessly discarded” each day.
GPs told to bin extra doses
Medical staff have also claimed that local authorities warned GPs they could not use extra doses on any staff or patients who have already had their first jabs.
The instructions were reportedly sent out across the country earlier this month, according to The Telegraph.
Dr Robert Morely, director of professional support at the Birmingham Local Medical Committee, told the publication that the orders are "extremely counterproductive, nonsensical and ludicrous".
He said: “This is ridiculous, bordering on the criminal, to actually be wasting vaccines when you have the worst global healthcare crisis for a century."
Dr Morley also said that GPs are struggling to book the exact number of appointments per vaccine due to the uncertainty of the supply chain. He added that some patients do not turn up after booking at short notice.
Instead of throwing away the leftover doses, Morley said: “The logical thing to do would be to use it as a second dose for healthcare workers, for example, who may be there in the building.”
More than 100,000 reportedly wasted
Doctors also said more than 100,000 doses of the Pfizer/BioNTech vaccine could have been thrown away during the first few weeks of the rollout after Public Health England (PHE) took weeks to revise its guidance on dosages.
The initial instructions on administering the vaccine when the UK approved the jab at the beginning of December said that five doses could be obtained from each vial.
But by December 17, Britain’s medical regulator MHRA confirmed to the Daily Mail that “small” amounts of the jabs were actually going unused.
The same day, NHS England issued guidance to the health staff on that vaccinators could administer the sixth dose after MHRA had approved it.
Dr Brian McGregor, a GP who chairs the BMA's Yorkshire regional committee, told the Telegraph that NHS England ordered his local clinical commissioning group to throw away any unused doses.
McGregor claimed they had been warned they would be "performance managed" on the issue.
"They control our contracts, payments, vaccine supply, regulation, and can make life unbearable," the doctor added.
Dr Julia Patterson, founder of Every Doctor, a campaign to protect the NHS and its workers, echoed the claims saying at least six different workplaces had told her organisation doctors had been forced to bin leftover doses.
The BMA's chair of council, Dr Chaand Nagpaul, told the newspaper: "Reports of vaccination sites feeling pressured to discard unused doses of the Pfizer vaccine are extremely concerning.
“This is absolutely unacceptable and morally wrong. Any wasted dose denies a real person the chance to be protected from serious illness or even death.”
An NHS spokesman told media outlets at the time: "There is absolutely no reason why vaccines should be wasted.
"Local vaccination sites should be managing their appointment lists to ensure all appointments are filled and they have a back-up list of patients and staff who can receive the vaccine at short notice."
Yahoo News has contacted NHS England for comment.
Watch: COVID-19: Pfizer vaccine is a big boost - now we have to decide how best to use it