Download now


A quick Q&A on Covid-19 vaccines

Last updated:

At last, some good news about Covid-19 – early trials have shown that one vaccine in development is 90% effective, paving the way for more. Here’s an update

Need to speak to a GP today?

Book appointment

Quick facts

  • Early trials show one vaccine is 90% effective within 28 days
  • It involves two doses, given 7 days apart
  • More than 100 other Covid-19 vaccines are currently being tested

A vaccine has always been the best hope for conquering Covid-19.

The good news is, two will be in production by the end of the year. Another may be available by early 2021. But we can’t look to this as a quick solution yet, and we should keep following government guidelines.

The race for a Covid-19 vaccine – latest news

Early trial data has shown a vaccine, developed by US pharmaceutical giant Pfizer and German company BioNTech, is 90% effective. It’s hoped that up to to 50 million doses will be produced this year, and up to 1.3 billion in 2021.

‘This promising news was released in a press statement last Monday,’ says Dr Annette Alaeus, Livi’s infectious diseases specialist. ‘We’re all eager to see the final result.’

Later this month, drugs company AstraZeneca will announce trial results of a Covid-19 vaccine it’s developing with Oxford University. Mass production of this vaccine is already underway.

Another vaccine, being developed by Moderna, could be available by early 2021 – and there may be others.

While there are still hurdles to clear, and big logistical challenges to overcome, experts are cautiously optimistic that the end of the pandemic could now be in sight.

With so many reports in the news, you might have more questions than answers. This quick guide will help.

How do vaccines work?

Vaccines contain a weakened or inactive section of a virus or bacterium, or a blueprint to make it. They can’t cause the disease. Instead, vaccines trick your body into thinking it has a particular infection, so your immune system produces antibodies against it.

Then, if you encounter the virus or bacterium again, your body is already equipped to defeat it.

How did they develop it so quickly?

On average, it takes 10.7 years to develop a vaccine. So to have what may be an effective vaccine in under a year is an extraordinary scientific achievement.

The Ebola vaccine, for example, which was previously the fastest ever developed, took 5 years to become a reality.

Around 80% of the genetic code of Covid-19 matches the SARS virus, so earlier research gave scientists a head start. And the code for Covid-19 – which provided lots of new information – was mapped less than 5 months after it emerged.

There has also been global collaboration and cooperation on a scale never seen before.

‘Due to this massive effort from so many companies and academic institutions to quickly get a vaccine for Covid-19, we might even discover vaccines against other coronaviruses that may appear in the future,’ says Dr Alaeus. ‘This could mean we’ll be better prepared for a possible new pandemic.’

More than 100 vaccines are in development, and 10 are in phase 3 trials – the final phase of testing before a vaccine or medicine is available to the public. Some 43,538 people are enrolled on the final trials of the Pfizer vaccine.

What do we know about the Covid-19 vaccine?

Two doses are given 7 days apart. Early results suggest this provides 90% protection within 28 days – but the final results may not be this strong.

More than a third of people on the Pfizer vaccine trial are from ethnically diverse backgrounds, and the upper age limit was 85. We don’t know whether the vaccine is as effective in these higher-risk groups, but our ability to make antibodies does deteriorate as we age.

There will also be logistical issues. For example, the vaccine has to be stored at around -70[1] °C – 4 times colder than a domestic freezer.

How quickly will a vaccine be available?

Because of funding agreements, the US government owns the first 100 million doses of the new Pfizer/BioNTech vaccine. But the UK government is said to have secured early access to 90 million doses.

The UK and all EU countries have secured early access to the AstraZeneca and other vaccines too, although we don’t know when these will be available.

Who will be vaccinated first?

National governments will decide who gets the vaccine in their countries.

In the UK this is likely to be the over-50s, frontline healthcare and social-care workers, and adults with underlying health problems like diabetes and asthma.

Read more about what we know now about Covid-19 and how to stay safe this winter.

This article has been medically approved by Dr Annette Alaeus, Livi infectious diseases specialist.

Other Articles

Covid-19 – Jan 26, 2022 
How to help your body recover from Covid-19
Dr Annette Alaeus, Livi’s infectious diseases expert, has advice on how to give your body the best recovery from Covid-19 — in both the short and long term
Covid-19 – Dec 20, 2021 
What do you need to know about the Covid-19 booster jab?
Why do we need another dose of the Covid-19 vaccine, who should get it and how will our bodies react? Dr Annette Alaeus, Livi’s Head of Infectious Diseases, answers your questions