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LONDON: The UK has become the first country to approve the Pfizer / BioNTech vaccine for widespread use.
The government has ordered 40 million doses and the first batch of 800,000 doses is expected to ship from Belgium, where the vaccine is manufactured, in the next few days.
It will suffice to immunize 400,000 people (two doses per person).
The UK drug regulator, the Medicines and Healthcare Products Regulatory Agency (MHRA), has also started an ongoing review of other vaccines in late-stage human trials, such as the AstraZeneca / Oxford vaccine and the Moderna vaccine.
If these vaccines also meet the high standards of efficacy and safety set by the agency, they will also be approved for mass deployment.
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The fastest a vaccine has been developed is the mumps vaccine, which took just four years from conception to commercialization. These latest vaccines broke that record by some margin, taking less than a year to develop.
But that does not mean that the corners have been cut. The MHRA has painstakingly studied the records of more than 40,000 vaccine trial participants from various backgrounds.
The vaccine’s efficacy – that is, how effective it is at preventing symptomatic COVID-19 under the test conditions – is 95 percent. That number is expected to drop slightly under real-world conditions.
And there were no serious side effects, although these will continue to be monitored as the vaccine is implemented.
(File Photo: AFP / Justin Tallis)
Health workers are expected to receive the vaccine first, as they are one of the most vulnerable groups. In addition, hospitals have the necessary ultra-cold freezers to store the vaccine, so logistically speaking, this is a good place to start.
DON’T LEAVE THE MASK YET
This is all fantastic news and good reason to be optimistic about the future.
But Peter Openshaw, professor of experimental medicine at Imperial College London, said it would be a “terrible mistake” to relax COVID control measures at this time.
So don’t throw away your mask and hug your grandma just yet. A report by The Royal Society, the world’s oldest independent scientific academy, says the restrictions are likely to remain in place for a few months, perhaps even a year.
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When you receive the COVID vaccine, you should not expect immediate protection against infection. White blood cells known as B lymphocytes first need to detect the antigen in the vaccine and then generate specific antibodies against it.
If you are exposed to the coronavirus, these antibodies stick to the virus and neutralize it.
The response of your immune system, generated by B lymphocytes, is known as the primary response and takes about two weeks to activate. Therefore, for two weeks after receiving the jab, you are still at risk of becoming ill from COVID.
Additionally, many COVID vaccines require two injections to provide complete protection. And the interval between strokes varies from 21 to 28 days.
A person receives a dose of the coronavirus disease (COVID-19) vaccine from BioNTech and Pfizer in this undated brochure photo, as Britain became the first Western country to approve a COVID-19 vaccine, in Mainz, Germany. (Photo: Reuters / BioNTech SE 2020 Brochure, all rights reserved)
Therefore, it will take about six weeks after the first shot for the vaccine to provide complete protection against COVID-19.
WE DON’T KNOW IF VACCINES STOP TRANSMISSION
Although the vaccines in late-stage trials appear to be very effective in preventing symptomatic COVID, we still cannot be sure that they will prevent transmission of the virus.
To do this, we would need a vaccine that provides so-called sterilizing immunity. This is where immune cells can bind to the virus to prevent it from entering cells where it can begin to replicate.
So even six weeks after getting the first puncture, you may still be infected with the coronavirus, even if you don’t get sick.
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Studies from the preclinical phase of the Oxford vaccine found that rhesus macaques that were immunized with the vaccine were protected from serious disease and had no evidence of lung damage.
But they still had a coronavirus infection in their upper respiratory tract and viruses shedding from their noses. If this is the same with humans, it would suggest that while they will be protected from symptomatic disease, they could still spread the virus.
At this stage, we don’t know if the Pfizer or Moderna vaccines don’t stop transmission either, though hopefully more studies will find out.
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Also, if you have been vaccinated, there is a small chance, at least one in twenty, that the vaccine will not protect you.
So even if you’ve been vaccinated, and full deployment may not be complete until the summer of 2021, you should still wear a mask, work from home if you can, and practice social distancing.
As for good hand hygiene, let’s try to keep it up: Viruses, probably including SARS-CoV-2, will always be with us.
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Manal Mohammed is Professor of Medical Microbiology at the University of Westminster. This comment first appeared on The Conversation
