Findings from a new Scottish study support offering a third vaccine dose to people previously on the shielding list and who are known to be clinically extremely vulnerable to COVID-19.
The study, led by Public Health Scotland and supported by the University of Edinburgh, considered whether people classed as clinically extremely vulnerable had the same level of protection from COVID-19 after two doses compared to the rest of the population.
People are designated to be clinically extremely vulnerable to COVID-19 if they have certain medical conditions or take specific medicines that affect their immune system. A weakened immune system not only puts some people at greater risk of experiencing complications with COVID-19, it may also reduce the effectiveness of the vaccines they receive.
Researchers found that people previously in this group had 66% protection against severe COVID-19 disease after two doses of any COVID-19 vaccine compared to 93% protection in those without high-risk conditions.
Discussing the findings, co-author of the study, Professor Helen Colhoun of the University of Edinburgh, said: “It is clear that getting vaccinated with two doses is an effective way of reducing the risk of getting severely ill from COVID-19.
“However, our study did show that people who were previously asked to shield as a result of being clinically extremely vulnerable to COVID-19 did have lower protection after two doses than those without their conditions.
“We found that out of over 3.5 million people who have had two vaccine doses in Scotland up to the 2nd of September 2021, there were just 330 cases of severe COVID-19. Almost half of these are in people designated as extremely vulnerable and most of the remainder have been in people with moderate risk conditions.
“The fact that we see an increase in protection from the first to the second dose gives hope that a third dose might increase protection further.”
On the 1st of September, the Joint Commission on Vaccinations and Immunisations (JCVI) recommended a third dose of vaccine for people who are most immunosuppressed.
Dr Nicholas Phin, Director of Public Health Science at Public Health Scotland, said: “The findings of this study confirm that all the vaccines approved for use in the UK continue to be highly effective at reducing severe illness and death from COVID-19.
“Whilst those who are clinically extremely vulnerable get, on average, a substantial level of protection to COVID-19, it will vary from person to person and by the nature of their vulnerability. We therefore welcome the JCVI advice and the subsequent rollout of the programme that prioritises a third dose for those who are known to be at most-risk from COVID-19.
“If you are contacted to receive a third dose then please do take the opportunity to bolster your protection against COVID-19. If you have not had any doses of a COVID-19 vaccine yet, you can protect yourself and others by registering online or finding your nearest drop-in vaccination centre via the NHS Inform website.”