There's really no other way to say it: Canada's (and Europe's) public health authorities are currently making a real hash of things as regards the AstraZeneca COVID-19 vaccine, and are actively contributing to the already worrying levels of vaccine hesitancy.
First, they tell us it's not proven to be safe and efficacious for over 65s, whereas in actual fact all they meant was that the initial test data did not include sufficient test subjects over that age. There is no reason to suspect that the vaccine is any less safe or effective for 66-year olds as it is for 64-year olds, and an abundance of real world data from the UK and Europe has shown it to be perfectly safe and very efficacious for any age group, ESPECIALLY over-65s. Anyway, both Canada and Europe changed their minds on that and, having put unnecessary worries in many people's minds, recommended that the vaccine be used for seniors too.
Then, there was the whole blood clot issue, as a result of which several European countries and Canada have ruled that people under the age of 55 should not get the AstraZeneca vaccine because of a risk of vaccine-induced blood clots (vaccine-induced prothrombotic immune thrombocytopemia, or VIPIT, if you really want the jargon). This is an extremely rare response that has occurred 25 times in Europe out of about 20 million AstraZeneca doses administered, lower than the rate of blood clots expected in the general population. There have been no blood clot events at all reported in Canada out of the 300,000 or so doses administered here.
However, some of the cases are an even rarer event, cerebral venous sinus thrombosis (CVST), which can cause fatal bleeding in the brain, and has led to the death of 9 people in Europe. They mainly seems to occur in people who have low blood platelet counts, arguably a pre-existing condition, and mainly affect people between the ages of 20 and 55 (or 63 according to some studies), the majority of them women.
Be that as it may, the week after the European Medicines Agency issued a report saying that it had investigated the issue and concluded that the vaccine is not associated with an increase in the overall risk of blood clots, and that the benefits of the vaccine far outweigh its possible risks, Canada has nevertheless issued its blanket warning that under-55s should not get the vaccine, at least for now. Most provinces have already followed suit, regardless of the fact that under-55s are not actually eligible to receive it yet in most provinces anyway.
This advice will probably change too, like the over-65s ban did, but not before lasting damage has been done among a jittery population already prone to vaccine hesitancy for much less scientific reasons.
Incidentally, advice to people who have already had the AstraZeneca shot - like me - is hard to find, but VIPIT symptoms usually occur within 4 to 20 days after the vaccination. So, if you haven't had any symptoms (persistent and severe headaches, seizures, blurred vision, shortness of breath, chest or abdominal pain) in that time, then you are probably fine.
UPDATE
A new report from the UK shows more and more cases of the AstraZeneca blood clot issue are occurring, a total of 30 cases from 18 million shots (all women between the ages of 25 and 65), of which 22 were the more serious CVST event, and there have been a total of 7 deaths.
British (and European) health authorities, however, insist that the vaccine is a good one, and that the benefits greatly outweigh the risks. As one Cambridge scientist points out, the risk of a blood clot outcome is around one in half a million, and a month's delay on vaccinating half a million people would, statistically, result in around 85 severe cases of COVID-19 requiring hospitalization, of which around 5 would be expected to die.
Looked at that way, AstraZeneca seems like a pretty safe bet. And, after all, no medication is completely safe for everyone. How many medicines have you ever taken where the impossibly fine print mentions "possible" side effects that include nausea, vomiting, shortness of breath, and ... yes ... death?
UPDATE UPDATE
More recent studies show that the risks of getting a blood clot are much higher for those who contract COVID-19 than for those who receive a vaccine, by a factor of between 8 and 10. That particular statistic really turns the overreaction to the blood clot issue on its head. Unfortunately, the damage to public confidence in the vaccines has already happened.
And here's a handy-dandy graphic to put things into perspective, for those with short attention spans:
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