Before now, a vaccine has never been developed and approved for public use in under four years.

The Pfizer/BioNTech Covid-19 vaccine has smashed that record. It was announced on Wednesday morning it would be rolled out in the UK next week after just a few months of research and development.

Studies have shown the jab to be 95% effective and works in all age groups. No safety concerns arose from clinical trials.

In total, Australia has agreed to buy 135 million vaccine doses, including 10 million from Pfizer. Australia also has deals for 34 million doses from AstraZeneca, 40 million from Novavax Inc and 51 million from CSL Ltd.

Usually it takes 10 years and this time it’s taken 10 months, so of course people are going to wonder if any shortcuts have been taken.Dr Jennifer Rohn

While the news is undoubtedly welcome and paves the way for a path out of the coronavirus pandemic, concerns about safety have been simmering in public throughout the year.

“I think the concern is quite understandable in some ways,” UCL medicine cell biologist Dr Jennifer Rohn told HuffPost. 

“Usually it takes 10 years and this time it’s taken 10 months, so of course people are going to wonder if any shortcuts have been taken.”

It’s undeniable that coronavirus vaccines have been developed with unprecedented speed. The previous record was four years, when the mumps vaccine was distributed in the 1960s.

Have there been any shortcuts?

In short, the answer is no. Rather than the result of shortcuts or the loosening of safety standards, the speed with which Covid vaccines have been developed is due to the phenomenal money and effort thrown at the problem – the UK government alone has spent £6bn in total to develop and procure them.

Even though some phases of the clinical trial process have run in parallel rather than one after another, the safety checks have still been the same as they would for any new medicine.

The trials take place in three sequential stages – also known as phases. The research will show whether a vaccine generates antibodies but also protects people from disease. They will also identify any safety issues.

Once the trials are complete, the information gathered by researchers is sent to regulators for review.

This is thoroughly analysed by clinicians and scientists before being approved for widespread use. Then, after approval from regulators, people can start to receive the vaccine.

PA Media

In total, Australia has agreed to buy 135 million vaccine doses, including 10 million from Pfizer.

How have the regulators acted so quickly?

Regulators have been carrying out “rolling reviews”, which means that instead of going through reams of information at the conclusion of the trials, they have been given access to the data as the scientists work.

A rolling review of the vaccine data started several months ago, PA Media reports.

This means regulators can start to look at scientific data earlier than they traditionally would do, which in turn means the approval process can be sped up.

Regulators sometimes have thousands of pages of information to go over with a fine-tooth comb – which understandably takes time.

We know a lot about vaccines and what we’re seeing in the trials is exactly what we expect to see…Dr Jennifer Rohn

June Raine, head of regulator MHRA, said a rolling regulatory process had been conducted as the vaccine was developed, but standards had been maintained.

She told a Downing Street press conference on Wednesday morning: “That doesn’t mean that any corners have been cut, none at all.”

Dr Raine said experts had worked “round the clock, carefully, methodically poring over tables and analyses and graphs on every single piece of data”.

More than 1,000 pages of data had been examined, she said.

How can it be ready next week if it’s only just been approved?

Pharmaceutical companies have already started manufacturing their vaccines so a stockpile would be available if they passed trials and gained approval

Usually large-scale production and distribution begins only after regulatory approval.

But in the case of Covid-19 vaccines, pharmaceutical firms have begun manufacturing before final approval had been granted – taking on the risk that they may be forced to scrap their work.

Has the vaccine been developed from scratch?

Again, the answer is no.

“There’s been an enormous amount of groundwork on these prototypes so we were quick off the mark from a research point of view,” says Rohn. “The actual trials are taking a long time and that’s where nothing is being compromised.

“No reputable regulatory body will approve this without a completed and successful series of clinical trials.”

What about possible long-term side effects?

While the immediate need for the vaccine does mean the longer term effects of the vaccine cannot be known just yet, it’s incredibly unlikely that there will be some mysterious and damaging side-effect that only becomes apparent later on.

Former chief scientific adviser, Sir Mark Walport, said earlier this month that from a “long history” there was “no reason” to expect that a new coronavirus vaccine would have long-term side effects.

He added: “If there are going to be side effects, there are the immediate ones.”

These of course would have been picked up in trials already conducted. In most clinical trials, any safety issues are usually identified in the first two to three months – a period which has already lapsed for most vaccine frontrunners.

Rohn said: “We know a lot about vaccines and what we’re seeing in the trials is exactly what we expect to see – a robust immune response, we’re seeing antibodies and T cells. Nothing that’s going in is incredibly earth-shattering – it’s RNA and protein.”

Does it matter if I don’t get the vaccine?

Yes, massively. But unfortunately the false belief that it doesn’t has been propagated by a number of people with large social media followings such as former Stone Roses singer Ian Brown.

There are three things to be considered here. 

Firstly, Ian Brown as no medical or scientific qualifications whatsoever so ignoring what actual scientists have to say about actual science in favour of him is a bit… daft.

Secondly, not everyone can be vaccinated. People undergoing certain medical treatments or those with compromised immune systems may not be able to safely take a vaccine.

As such, they are relying on the wider population to take the vaccine, develop herd immunity, and therefore indirectly protect them from Covid-19.

The third thing to consider is that herd immunity for a disease is typically achieved when 70% to 90% of a population is vaccinated.

So while Mr Brown alone deciding to not take the vaccine is not problematic, tweeting and encouraging his 148,000 followers to do the same very much is.

“It’s quite a shocking thing to say: ‘I’m going to sit back and reap the benefits of vaccination without actually getting the vaccine myself,’” says Rohn.

“I think that’s completely selfish because not everyone can get vaccinated. There are people who are too vulnerable and they’re immunocompromised and they’re relying on everyone else to do the right thing.”

How will the UK prioritise which groups will receive the vaccine?

Here is its new priority list:

  1. Older adults resident in a care home and care home workers
  2. All those 80 years of age and over. Front line health and social care workers
  3. All those 75 years of age and over
  4. All those 70 years of age and over
  5. All those 65 years of age and over
  6. All Individuals aged 16 to 64 with underlying health conditions.
  7. All those 60 years of age and over
  8. All those 55 years of age and over
  9. All those 50 years of age and over
  10. The rest of the population (priority to be determined)

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