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A new, more contagious virus variant is spreading, vaccines are in short supply, and production likely won’t keep up with gigantic demand for months. Under these conditions, how can the available vaccine doses best help protect people from life-threatening disease?
What seems like an exercise in health care is now a reality: while the seemingly more contagious variant B.1.1.7 of coronavirus is spreading, vaccination programs in European countries are only gaining speed very slowly.
With this in mind, Britain has decided to take an unusual step: people should not receive the second vaccination dose of the Biontech / Pfizer and Astrazeneca products approved there around three weeks after the first dose, but up to twelve weeks later.
“Prioritizing the first dose of vaccine for as many people as possible protects as many people as possible in the shortest amount of time and therefore also has the greatest influence on preventing deaths, serious illnesses, and hospital admissions.” writes the British NHS health service. “In practice, this means that the second dose of the vaccine is given at the end of the recommended vaccination schedule of up to twelve weeks.”
So the idea is: it is better to protect as many people as possible to some extent than optimally fewer, to avoid as much suffering as possible. However, it is impossible to predict whether the plan will work.
The manufacturer Pfizer noted that the phase III study looked at the effectiveness of the vaccine after two doses administered three weeks apart. Research shows that some protection builds up in some cases as early as twelve days after the first vaccination. But it does not provide any data beyond a 21-day period, because then the second vaccination in the study took place.
Therefore, the decision is made in the absence of secure information. Even if some figures are currently circulating about how well a single dose of vaccine supposedly protects: today no one knows exactly whether these values are still correct after two, three or six months. That can only be found out through studies.
One thing is certain: two doses are more effective than one. However, postponing the second vaccination could give the wrong impression that it is not important and therefore cause a relatively large number of people to no longer attend the second vaccination appointment.
“No significant commitments can be expected”
However, some scholars consider the British approach to be sensible in the current situation. For example, vaccine researcher Leif-Erik Sander of the Berlin Charité said, according to the Science Media Center, that he currently considers a strategy to be more effective, “in which as many people as possible get vaccinated as soon as possible is more effective, that is, without withholding the vaccine doses for the second vaccination. ” According to the recommendation of the Permanent Commission on Vaccination, the second vaccination dose of people who have already received the first dose has priority over the first vaccination of others, and for this “the vaccine should be put aside.”
“In my opinion, accepting a possibly longer interval until the second vaccination is harmless, at least for the mRNA vaccines, since the vaccines in the studies showed a very high level of protection against Covid-19 only ten days after the first injection, “says Sander. . The second vaccination could easily be delayed a bit, “with no significant reductions in efficacy expected.” But that’s certainly only a temporary strategy. And it is important that all vaccinated people receive a second vaccine.
Why are vaccines given in more than one dose? “To increase the quantity, quality and longevity of the antibody response”, explained the immunologist Akiko Iwasaki. The expert emphasizes that she is still in favor of giving people a second dose of vaccine, but due to the current urgency, the second dose can be postponed until there is more vaccine. The infection rate of variant B.1.1.7 convinced them of this.
According to the Science Media Center, Peter Kremser, a specialist in tropical medicine at Eberhard Karls University in Tübingen, also considers the British approach to be “fundamentally very useful.” “As with other vaccines, you can probably give the second dose after two or three months, since the first dose seems to be very effective. If the effect of the first vaccination does not diminish rapidly over time, the second vaccination could also take place later, for example after six months. We don’t know yet. “
American immunologist Anthony Fauci said on Friday that the United States would not follow the British example and delay the administration of the second dose of vaccine. The optimal time for the second dose is known from clinical studies. But he also said there were arguments in favor of the British approach.
The British Medical Association, whose members now have to rebook existing second vaccination appointments for thousands of people, has very practical criticism of the procedure in Britain. The logistical effort is huge and moving would be terrible for high-risk patients.
However, there is a comparatively simple way to vaccinate more people in a timely manner: With the best tools, you can get six rather than five doses of vaccine from a bottle of Biontech vaccine. However, so far, the EU pharmaceutical authority has allowed Ema to extract five doses of the vaccine, and in the product information for Comirnaty repeatedly instructs doctors to discard the rest, despite Ema herself confirming to SPIEGEL’s request that Biontech had informed them of the sixth dose prior to approval. would have. Now the authority wants to check if the product information changes. As a result of the change, Germany would have 800,000 vaccine doses per week instead of the previous 670,000 doses per week, if the withdrawal of six doses were a consistent success, without further effort.
And furthermore, the vaccination doses that have already been delivered first would have to be administered in Germany. While already 1.3 million cans delivered only just under 190,000 people received the first dose of the vaccine.
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