One vaccination centre in Paris is offering people Moderna vaccines, even after they have already had two Pfizer shots and want a third, according to France Info .
The President of France’s scientific council, Jean-François Delfraissy, told the Senate this week: “If we do not use our Moderna vaccines, we will not have enough to vaccinate [throughout] January. It is not a second choice, it is a first choice, like Pfizer.”
Third dose appointments rocketed following President Emmanuel Macron’s address about changes to the health pass on November 9th. The rollout of booster doses to all adults added to the pressure on vaccine stocks.
Managing supplies has been the priority. At the beginning of December, France had 20 million doses of the Moderna vaccine and 6 million doses of Pfizer, according to official figures.
But the Direction générale de la Santé has rejected claims that the Moderna vaccine is being pushed because it is nearing its use-by date. “No Moderna dose in storage will expire before February 2022,” it said in a statement.
“All the doses delivered have an expiry date at least three months [away] and, as is usually the case, doses delivered first are those with the shortest expiry date in order to avoid any loss of dose.”
Is there a risk to mixing vaccines?
It’s understandable that people who have had two doses of the same vaccine, Pfizer for example, may prefer to stick with the brand they know.
But the Moderna and Pfizer vaccines have been developed based on the same RNA technology, and have regularly been referred to as “twins” by French health authorities.
Health Minister Olivier Véran said on France Info in early December: “I say to French people who have had, for example, two doses of Pfizer and who are worried about having Moderna: no problem. Likewise, the French who have had Moderna twice and who are offered Pfizer: no worries, it’s the same.
“The only difference is that if you are under 30, we prefer to give you Pfizer rather than Moderna.”
Dominique Deplanque, president of the French Society of Pharmacology and Therapeutics, added: “Pfizer and Moderna are based on the same principle, their level of effectiveness is comparable and the profile of adverse effects is generally the same, aside from this small increased risk of rare and non-severe myocarditis in young adult males.”
They’re pretty much the same, then?
Not quite. Doses of Moderna for the first two jabs are more voluminous than those of Pfizer: the former has 100 microgrammes of mRNA per dose, compared to 30 microgrammes for the latter.
So far, scientific studies back up official claims that there’s no risk in mixing vaccines.
“It poses no problem, neither in terms of safety nor efficacy, and it even gives rather better results,” said respected immunology professor, Alain Fischer, who has been charged with co-ordinating France’s vaccine rollout.
“By combining the two vaccines, we can vaccinate everyone very quickly. If we can’t use the Moderna vaccine properly, then we’ll slow down the vaccination campaign.”
For the booster dose, health professionals administer 50 microgrammes of mRNA with the Moderna vaccine, and 30microgrammes of the Pfizer. As a result of the higher dose, protection against Covid-19 is slightly higher after a Moderna injection. The risk of side effects – while still small – is also slightly increased.
What about side effects?
Since the start of vaccination in France, the Agence nationale de sécurité du médicament (ANSM) has identified 15,959 adverse cases out of 11,418,700 injections of Moderna vaccine in France, and 71,624 cases of adverse effects out of 83,735,200 injections for Pfizer, according to latest figures.
The majority of side effects are “expected and not serious” among patients dosed with the Pfizer vaccine, ANSM reports. For Moderna, “a large number of cases concern delayed local reactions that are not serious”.
But, while tolerance to the Pfizer vaccine is higher than the Moderna, the recommendation is still to have a booster dose, regardless of brand.
Anne-Claude Crémieux, specialist in infectious diseases at Saint-Louis hospital in Paris, told France Info: “We must leave the choice to the French. I respect this choice because it is reasoned. But my message is clear, it is better to have a Moderna vaccine than no booster.”
So there’s still a choice?
Yes, there is. Older patients attending vaccination centres who want to have a booster of Pfizer will receive one.
For under-30s, Pfizer is the only vaccine authorised for a booster dose.