Herd Immunity No Longer an Option Due To Delta Variant

Head of Oxford Vaccine Group says vaccination won’t result in herd immunity due to emerging coronavirus strains.

Herd Immunity No Longer an Option Due to Delta Variant
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Herd Immunity No Longer an Option Due to Delta Variant

Recently a vaccines expert and head of the Oxford Vaccine Group, Professor Sir Andrew Pollard, told British MPs to stop focusing on herd immunity. COVID strains like the Delta variant have made it apparent that even fully inoculated people may still become infected; this possibility only increases with potential new mutations.

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Sir Andrew warned the All-Party Parliamentary Group: ‘anyone still unvaccinated at some point will meet the virus.’

What is herd immunity?

Herd immunity is when enough people in a population or community have become protected or resistant to a disease or virus through previous infection or immunisation that the illness can no longer spread.

The percentage of people that need protection from a virus to halt its spread varies, but according to Our World in Data, 75%-80% of people will needcoronavirus protection to reach herd immunity.

The Government recently announced that three-quarters of the UK’s adult population are now fully vaccinated. The Department of Health and Social Care released figures showing a whole 86,780,455 COVID shots have been given, with 89% of people receiving their first dose and 75% now being fully vaccinated.

However, Sir Andrew has warned that while vaccines may slow the spread of coronavirus, highly transmissible strains such as the Delta variant may not be contained altogether by jabs.

Sir Andrew continued: ‘We know very clearly with coronavirus that this current variant, the Delta variant, will still infect people who have been vaccinated, and that does mean that anyone who's still unvaccinated, at some point, will meet the virus.’

I think we are in a situation here with this current variant where herd immunity is not a possibility because it still infects vaccinated individuals.

Sir Andrew revealed to MPs that a new variant that’s even better at transmitting amongst vaccinated people couldn’t be ruled out, meaning the vaccine programme should no longer be geared towards reaching herd immunity.

However, the vaccines expert was hopeful that the UK would soon see ‘increasing confidence’ around their pandemic situation:

I think this next six months is a really important consolidation phase and in that shift from the epidemic to the endemic, which is the living with COVID. That doesn't mean that we live with it and put up with it - we still have to manage those cases of patients who become unwell with it.

Even if you can get infected it’s still important to get vaccinated

Despite vaccines effectively protecting people against coronavirus, a small number of breakthrough cases will always be expected. This is because no vaccine is 100% effective.

Additionally, the Delta variant, the UK’s dominant strain, can cause more severe infections and spread faster than the early forms of COVID, even amongst vaccinated people.

However, this doesn’t mean that coronavirus vaccines are useless or ineffective. In fact, COVID vaccines become even more critical when it comes to mutated strains of the virus. Even if vaccinated adults become infected, they are sick for a much shorter period, and their risk of severe illness and hospitalisations are drastically reduced. Those who are fully inoculated are also infectious for a shorter amount of time, reducing the transmissibility of the virus.

COVID-19: Immunity from infection could be more effective than jabs against Delta variant COVID-19: Immunity from infection could be more effective than jabs against Delta variant