Lessons from Europe’s third coronavirus wave

Europe is facing a dangerous, new surge of COVID-19 cases, just as Italy, France and Germany suspend use of the AstraZeneca vaccine. Dr. Barry Bloom, former dean of the Harvard T.H. Chan School of Public Health, talks with The World’s Marco Werman about what lessons the surge might offer US scientists and public health officials devising strategies to beat the new variants.

TRANSCRIPT:

Marco Werman:
Most Italians are shuttered indoors today, and that’s because Italy saw a 15% spike in COVID cases last week powered by more contagious coronavirus variants. Meanwhile, Italy, Germany and France have all suspended the use of the AstraZeneca vaccine after reports that several people who received the vaccine developed the blood clots. Dr. Mariangela Simao with the World Health Organization, said it’s routine to look into any potential adverse side effects when they occur. She also said the general data has not found a higher rate of blood clots linked to the vaccine.

Mariangela Simao:
We are seeing this is a precautionary measure because we are still investigating.

Marco Werman:
For the latest, we reached out to Dr. Barry Bloom, former dean of the Harvard School of Public Health. I asked him to describe the surge we’re now seeing in Europe.

Dr. Barry Bloom:
The surge is not unexpected as a variant that was originally found in the UK called B.1.1.7, which seems to spread about 50% more rapidly and produce more serious consequences when people are sick, is spreading across the continent. And hence the concern about the AstraZeneca vaccine is a major concern.

Marco Werman:
So, yeah, let’s talk about that. Italy, France and Germany have all suspended the use of AstraZeneca. I mean, what impact is that likely to have?

Dr. Barry Bloom:
So AstraZeneca is the least expensive of the vaccines. It only requires refrigerator temperature. It can be stored for a couple of months. So for getting a vaccine out quickly, even though it’s a two dose vaccine, it’s very appealing. What has happened is that in the last months, there have been reports of excessive clotting thrombosis. Twenty-two reports from multiple countries and all had the AstraZeneca vaccine. And that has caused a kind of panic in the countries because of alarm raised in the press.

Marco Werman:
I mean, a lot of experts still say the benefits of the AstraZeneca vaccine outweigh the risks. Do you agree with that? And do you also understand why countries like Italy and France have suspended its use for the time being?

Dr. Barry Bloom:
How does one know whether, when you vaccinate 3 million people with the AstraZeneca vaccine and somebody dies of a heart attack and somebody gets thrombosis and somebody has a stroke and somebody commits suicide, how do you know if that’s related to the vaccine? It turns out it’s pretty hard. And the way WHO has dealt with it is you ask, ‘What is the rate we know about heart attacks or strokes or suicide or thrombosis prior in those countries to there being the availability of a vaccine or COVID?’ And the answer is: ‘It’s very, very low.’ And if 3 million people are vaccinated and only 22 got thrombosis, that turns out to be statistically in the same range that would happen if there were no vaccination in the same countries. That is not proof that the vaccine didn’t do that. But what it certainly is evidence that it hasn’t raised the level of thrombosis greater than would be expected if there were no vaccine. And on that basis, WHO is saying there is yet no evidence that the vaccine caused the thrombosis. From a science point of view, lack of evidence is not evidence that the vaccine isn’t making harm. And that leads to the uncertainty that these countries have.

Marco Werman:
So how long will it take to answer that question, to see whether the scientists can connect the dots? In other words, how long do you think this suspension of AstraZeneca vaccine will last?

Dr. Barry Bloom:
At the technical level, I think one wants to know is did they all come from the same batch? Did they all come from the same manufacturer? That is, could some artifact have occurred in one batch, or in one factory, that makes the vaccine that could explain it. And I would point out that the US had received an early request for approval of the AstraZeneca vaccine, and there had been problems with getting detailed information that the US FDA requires. And that has led AstraZeneca to run a trial in the US. So we will get pretty good data, I think by the toughest review standards on the AstraZeneca vaccine, perhaps in a month or so. And we will be looking very hard, I am sure, for thrombosis of that vaccine as produced in the US and tested on people in the US.

Marco Werman:
Dr. Barry Bloom is former dean of the Harvard School of Public Health. Thank you very much for your explanations.

Dr. Barry Bloom:
Happy to be helpful and be safe and get your vaccine.