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Third dose versus booster – what’s the difference?


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We’re familiar with hearing the terms ‘booster jab’ and ‘third dose’, but what’s the difference? They’re not the same, and both are really important in protecting us against coronavirus. 

The Joint Committee on Vaccination and Immunisation (JCVI) announced in September that people with severely weakened immune systems at the time of their first and/or second COVID-19 vaccination, would receive a third dose as part of the standard vaccination schedule.   

Its purpose is to increase their level of protection against the virus, because they will not have reached the same levels of immunity as others after their two primary doses. Then, around six months later, that person should receive a booster jab. 

Booster jabs help maintain and extend the length of protection received from first and second vaccinations. They’re being rolled out to eligible people starting by invitation to those most at risk. That roll out will extend to all people aged 50 years old and over, and this week the government has said that anyone eligible can now get their booster jab from their nearest walk-in vaccination centre, so long as it’s been six months since their second jab. You can also book an appointment online via the National Booking System.

The invitation people receive to come forward for their third dose or booster jab will have taken into account their health at the time of their first or second vaccinations. But if you’re concerned about whether you’ve been invited for the right one at this stage, please contact your GP. 


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