Vaccination to Protect Against COVID-19 Illness and Death - Where Next?
In the UK vaccinations using two main vaccine options Pfizer BioNTech and Oxford-AstraZeneca are well under way in the most vulnerable age groups, those over 70 and those with the highest risk of exposure to covid-19 infection such as healthcare workers and those in care homes looking after vulnerable residents.
As we approach the wider roll-out of vaccination for younger age groups and those who are at risk because of underlying health problems even more difficult decisions will need to be made. Government directives are based on medical and scientific advice on those most at risk of being exposed to covid infection and those whose risk of more serious illness and possibly death from COVID-19 if they become infected.
The next phase of vaccination will be further complicated by the need to start revaccinating with the second dose of vaccine in groups who have already had their first dose but who remain vulnerable. Professional advisers are on a steep learning curve as they juggle priorities across the wider population and some possibility that vaccine supply may slow down as world-wide demand increases. The UK is in a very favourable position as new vaccines come along, and as we have a very strong national research teams to test the many questions that will arise until we can finally control this pandemic. Nevertheless, everything will take time and many questions remain to be answered.
One of the most interesting new studies reported this week is a trial to test what the impact might be of mixing vaccine doses. We reported last year that first and second doses of a given vaccine should be of the same type. This still holds true, and at present, anyone who has had one dose will be offered the same vaccine for their second dose. However, if second vaccine doses are delayed, it makes sense to ask the question “are there any reasons why a different vaccine from that given in the first dose cannot be used for the second dose?” .
It will be several months before we know the answer to this but by testing it in a well-controlled trial, we will at least know whether it is a viable and useful option. About 800 peopled will be asked to volunteer for the trial and everyone will be monitored fully throughout the study and for a period of follow-up.
To control this pandemic fully will need answers to many more questions over time but the progress made to date is phenomenal. We also believe that the huge research effort into to Covid-19 treatment will benefit many other conditions -perhaps including MS. Let’s hope we are right!