While vaccination campaigns are starting in Europe, the administration of the Comirnaty to certain so-called sensitive categories continues to raise questions. This is particularly the case for pregnant women and people prone to severe allergic manifestations.
Six days after the green light from the European Union, almost all the countries of the bloc launched their vaccination campaign against Covid-19 on Sunday, December 27. European Commission President Ursula von der Leyen hailed a “touching moment of unity”, saying the vaccine would “gradually return to our normal lives”.
With an estimated efficacy of 95% and a high level of tolerance in the general population, the American-German vaccine Pfizer-BioNTech represents enormous hope. But if the benefit-risk balance seems favorable in the overwhelming majority of cases, the scientific debate has not been settled for administration to all categories of the population.
Should the vaccine be contraindicated for certain categories of the population? No response for the moment because several groups were not included during the first clinical trials of the vaccines.
“Pregnant women as well as children are not part of the first phases of clinical trial testing because they are categories considered to be more vulnerable”, explains Philippe Amouyel, professor of public health at Lille University Hospital, contacted by France 24. “C ‘is a basic rule of clinical trials: it is generally estimated that several years of observations are necessary on the rest of the population before expanding the tests to these categories of people. ”
Immunocompromised people (with a weak immune system) are also excluded from the trials, as well as people who have already had Covid-19. However, if there is a lack of data to assess the effect of the vaccine on these types of populations, all are not in the same boat, according to Professor Jean-Daniel Lelièvre, specialist in vaccinology and head of the immunology and diseases department. infectious diseases at Henri-Mondor hospital in Créteil, interviewed by France 24. “There are categories for which we have questions. For example, it is believed that the effectiveness will be less in people who are immunocompromised by their conditions. We also have questions about people who have already had Covid because we do not know post-infection immunity. However, these two categories do not raise concerns about the risks of the vaccine, unlike pregnant women and people with severe allergies. ”
A risk “to be determined” for pregnant women
While immunocompromised people should consult a doctor first, the vaccine is not recommended for them. Specialists also agree that vaccination of under 16s is not necessary. But for pregnant women, recommendations vary by country. In the United Kingdom, the first country to launch its Covid-19 vaccination campaign on December 8, they are excluded from the program.
“There is no evidence that the vaccine poses a risk to pregnant or breastfeeding women, but the available data are insufficient to be able to administer them”, one can read on the site of the British government agency of health NHS. Instructions very different from those of the American authorities, which authorize the vaccine despite the absence of tests.
In France, the Haute Autorité de Santé (HAS) advises against it without prohibiting it. Germany, for its part, considers that it can be administered but only on a case-by-case basis.
“There are two aspects to differentiate, global regulation and then the assessment of the benefit-risk balance for the person” explains Philippe Amouyel. “We know that the elderly have the best balance since they develop more serious forms. Conversely, the youngest have little risk of developing severe forms and are clearly not a priority of the vaccination campaign. For pregnant women the risk remains to be determined, ”he concludes.
“Covid-19 infection poses a higher risk than that of vaccination”, recognizes Jean-Daniel Lelièvre. “But all drugs are not recommended for pregnant women, it is an intangible precautionary principle. If they want to get pregnant, we recommend that they get vaccinated as soon as possible or, if the pregnancy is already in progress, to be very careful and not to take any risks. ”
Severe allergic manifestations
Another category presenting a potential risk, people likely to manifest serious allergic reactions of the anaphylactic type (rapid and violent reaction which can sometimes lead to death if an adrenaline shot is not administered). Several such cases have been detected during the administration of the vaccine in the United Kingdom and the United States.
Anaphylactic reactions can be caused by food allergies (peanuts, nuts, fish and seafood, etc.), medication, or even stings from wasps, bees or hornets. They can result in a variety of symptoms such as breathing problems, vomiting, and rashes.
In the United Kingdom, two people who have shown serious allergic reactions in the past presented anaphylactic reactions to the vaccine, we learned the day after the first injections.
“Anaphylactic reactions represent around 5% of allergic reactions, so they are very rare”, underlines Philippe Amouyel. “Of course, special attention should be paid to those who have already shown this kind of reaction. The trouble is, some people are susceptible to severe allergic reactions but don’t know it. That is why it is important to monitor patients after the injection. ”
In the United Kingdom, since the observation of cases, the Medicines Agency (MCA) advises against vaccination of people who have presented this type of disorder in the past. If this is also the case in France, Germany has not yet decided the question. For their part, the United States continues to vaccinate this type of profile, under close surveillance for the first 30 minutes after administration.