November 25, 2020

COVID-19 Vaccine: A fresh start

There is no doubt that 2020 has been a long, hard year. With the endless threat of new measures and long lockdowns, it is safe to say we could do with some good news. Finally, we have a glimmer of hope.

First, Pfizer (Pharmaceutical company) announced the interim results of its vaccine, shown to be over 90% effective in preventing symptomatic COVID-19 in late stage trials. Then we heard of Sputnik V – the Russian direct investment fund vaccine also showing 92% efficacy in human trials. A little while later Moderna (Biotechnology company) announced it’s vaccine showed even higher levels of efficacy– 94.5%. Finally, in the last couple of days, Oxford University and AstraZeneca (Pharmaceutical company) announced that their partnership vaccine was 70.4% effective, however this value increased to 90% when given as a half dose followed by a full dose.2,3


What do these efficacies actually mean?

The definition of efficacy is: the performance of a treatment under ideal and controlled circumstances. Effectiveness is different as it relates to the performance of a drug under real-world or unideal conditions.4

Taking the Pfizer/BioNTech (Pharmaceutical/Biotechnology company) vaccine as an example, 90% efficacy would mean that out of 94 people with confirmed COVID-19, the vaccine prevented symptoms for 90% of those who received the vaccine compared with placebo. This is very high and will probably change by the end of the study.4

At the moment, it is expected that regulatory bodies will pass vaccines that are deemed safe and have efficacy values above 50%.


What still needs to be done before the vaccine for COVID-19  is rolled out?

Clinical trials must of course show that the vaccine is safe. After which release will be contingent on 2 other factors:

  • The UK’s regulatory body Medicines and Healthcare products Regulatory Agency (MHRA) must deem the new vaccine safe, effective and of high enough quality.
  • Large scale development of the vaccine to allow for billions of doses.5


Based on these blockers, when can we all expect to be vaccinated?

This will depend most likely on age. The UK government is hoping to vaccinate some of the most at-risk groups before the end of the year, such as those in care homes and over the age of 80. This has been decided as the older you are, the more likely you are to become seriously ill or die from COVID-19.

In springtime, over 50s are thought to be prioritised, after which wider groups of people may be offered a vaccine. It is not yet known whether people with underlying health conditions and those from ethnic minority backgrounds will be prioritised in the same way elder age has.6

Great achievements are being made and even with the barrier that lie ahead we could never envisage the speed of vaccines development for COVID-19 earlier on this year – finally there is hope.


  1. Image – Picture of Influenza vaccine (