Researchers in Britain have discovered that just one dose of the Pfizer/BioNTech vaccine doesn’t sufficiently protect people against other coronavirus variants.
In light of the findings, researchers are calling on public health officials to administer second doses to as many people as possible. Professor Danny Altmann at Imperial College London, who co-authored the research, explained:
We’re looking rather vulnerable to variants after one dose.
Single dose of COVID vaccine doesn't provide enough protection against variants
For the study, researchers followed 731 British health workers for several months. Nearly half of those who participated in the study caught coronavirus in the first wave of the pandemic, while the rest had not been infected. The study found that those who were not infected suffered a much weaker immune response after one dose of the Pfizer vaccine than those with a previous infection.
For those who had not been infected previously, one dose of the Pfizer vaccine provided antibodies that were 11-25 fold lower when it came to the B117 variant than the original coronavirus strain ‘resulting in the majority of individuals falling below the protective threshold.'
The research findings were also concluded to apply to the P1 variant first discovered in Brazil as well as the B1617 and B1618 variants, which were first detected in India.
For those infected previously, one dose of the Pfizer vaccine provided a strong enough immune response to fight off both the British and South African variants. Professor Rosemary Boyton who co-authored the study, revealed:
The study is basically showing that if you’ve had prior COVID-19, and then you’ve had a single dose vaccine, you are really in a different league in terms of your immune response. It’s almost like the infection has acted as a prime and the first dose has acted as a boost.
Two doses of the Pfizer vaccine will provide the best protection
Dr Altmann revealed that the study serves as a precautionary tale, warning people to continue to be vigilant against COVID even after they’ve had their first jabs:
One dose in terms of all of our measurable immune parameters of [the Pfizer vaccine] really does look very, very feeble and all the more so against variants.
And yet whatever the level of immunity that it’s induced, it’s certainly been enough to have had some impact. But it’s really very, very weak compared to two doses. My message from that would be hang on in there for your second dose.
Despite the warnings, researchers are still urging the public to get vaccinated against COVID as both doses of Pfizer is still efficient to protect against the virus and its strains:
We’re actually saying the vaccines are incredibly good. But what we are saying for a country for example like the UK that has the majority of its vaccinated people on one dose and also has one eye on the horizon for any incoming variants of concern, that’s a potential real vulnerability. And a solution would be to keep up your guard on the surveillance of variants and get the second dose to people.