4TH DOSE. The vaccine booster reboosts the immune system and limits the serious forms of Covid-19. The HAS recommends its administration from the age of 65 in France. For who ? Is it mandatory? What recommendations? How long after the 3rd injection? With Pfizer or Moderna? Answers.
[Mis à jour le 4 avril 2022 à 16h33] The vaccination more fragile facing covid is very important, especially with the rise in cases observed since March. On March 29, European Health Ministers instructed the European Commission to working on a common position on the injection of a 4th dose of coronavirus vaccine. “Scientific data is beginning to emerge that shows a decrease in the immunity conferred by the third dose four months after this third dose in people aged 60 and over“said Olivier Véran during the March 29 meeting of the Council of the European Union.Today we see States which have opened the fourth dose to those over 75, others for over 80s, this is the case in Franceanother, the Netherlands, to over 60s, others haven’t opened it yet, so This raises legitimate questions“, explained the Minister of Health. Germany currently recommends this fourth dose people over 70, particularly vulnerable people and healthcare workers. In France, the High Authority of Health also recommend this extra dose”people aged 65 and over, at very high risk of a severe form of the disease and/or polypathological and who want it”. The booster vaccination (2nd, 3rd or 4th dose) allows boost the immune system and to limit severe forms of coronavirus infection. Who should do 4 doses today in France ? Is it mandatory? How long after the third injection ? What indications? With which vaccine? Pfizer or Moderna?
Who should take a 4th dose of vaccine in France?
Since March 14, thePersons aged 80 and over who have received their booster dose for more than 3 months and all patients immunocompromised (no longer just “severely immunocompromised”) can carry out a 4th dose of vaccine against Covid-19, as announced by Jean Castex on March 12 in the columns of Parisian. In accordance with the advice of SVOC of November 2021, the severely immunocompromised people concerned by the 4th dose are:
- solid organ transplant recipients,
- recent bone marrow transplant recipients,
- dialysis patients,
- patients with autoimmune diseases undergoing aggressive immunosuppressive treatment such as anti-CD20 or antimetabolites,
- patients with certain types of lymphoma treated with anti-CD20 or BTK inhibitors,
- patients with chronic lymphocytic leukemia,
- patients with rare forms of primary immunodeficiency,
- myeloma under treatment
The High Authority of Health recommends a fourth dose of vaccine “people aged 65 and over, at very high risk of a severe form of the disease and/or polypathological and who so wish, within the framework of a medical decision shared with their healthcare team, taking into account their individual medical situation“. The government has not yet confirmed it.
Is the 4th dose mandatory?
The fourth dose of coronavirus vaccine is not mandatory but “opened“, i.e. possible for people aged at least 80 and for all immunocompromised patients, said Prime Minister Jean Castex on March 12.
Tomorrow, a 4th dose for everyone?
On March 29, European health ministers instructed the European Commission to work on a common position on the injection of a 4th dose of coronavirus vaccine. “Scientific evidence is beginning to emerge that shows a decrease in immunity conferred by the third dose some four months after this third dose in people aged 60 and over“, declared Olivier Véran during the March 29 meeting of the Council of the European Union. “Today we see states that have opened the fourth dose to those over 75, others for over 80s, this is the case in France, another, the Netherlands, for over 60s, others have not yet opened it, so this creates legitimate questions“, explained the Minister of Health. Germany currently recommends this fourth dose for people over 70, particularly vulnerable people and healthcare workers. “HAS considers that it is not not relevant to currently recommend the administration of a second booster dose in the general population” in a March 18 statement. Ella recommends it to people over 65 at very high risk of severe form of Covid. These people are prone to theimmunosenescencethe phenomenon of age-induced loss of immune system efficiency of the individual and in particular antibodies playing a role in the infection and transmission of Covid-19. “In-depth reflection is underway in order to arrive at recommendations for a medium- and long-term anti-Covid-19 vaccine strategytaking into account in particular the imminent arrival of new vaccines and vaccines adapted to the various circulating variants, the issues of acceptability by the population as well as all the immunological and clinical data available” specifies the HAS.
What do the vaccine production laboratories ? Stéphane Bancel, CEO of Modernahad assured, during a press conference on January 6 that a 4th dose of anti-Covid vaccine will most likely be necessary: “I still believe that we will need boosters fall 2022 and beyond.“Albert Bourla, CEO of Pfizersaid on BFM TV Monday January 17: “At the moment it is important to have three doses for a complete vaccination, maybe a fourth dose a bit later for the general population. We are in the process of testing the fourth dose but we do not have any data yet. At month of March, we will have the data on the efficacy of a fourth dose.”
How effective is the 4th dose?
“After a booster shot with the Pfizer vaccine, vaccine efficacy against hospitalizations was 90% and decreased to approximately 85% after 5 to 9 weeks and then 75% after 10 to 14 weeks. After a booster with the Moderna vaccine, the booster efficacy against hospitalization was 90-95% up to 9 weeks after vaccination“ indicates the HAS in its opinion from March 17, 2022.”Vaccine efficacy against symptomatic infections was similar for Omicron’s BA.1 and BA.2 subline“ adds the Authority based on the data of a study. “Epidemiologically, the proper conduct of the primary vaccination and booster vaccination campaigns would bring greater effects than the implementation of a second booster dose (4th dose, editor’s note)“ defended the COSV in its opinion. “In France, hospitalization, critical care admission and death data from the DREES also suggest that the recall would effectively protect against severe forms.although protection is lower against the Omicron variant than against the delta variant” specified the COSV. “The ‘hybrid’ immunities (vaccine and infection) also confer better neutralization capacities. However, faced with the current very strong viral circulation, it is very likely that the proportion of the population with hybrid immunity is increasing.“says the COSV again.
How long does it take to take your 4th dose?
► At age 65: HAS recommends respecting a time limit ofat least 6 months after the first reminder.
► At 80 years old and for the immunocompromised: the fourth dose of vaccine is for those who have received their booster dose since more than 3 months.
► In severely immunocompromised people, the fourth dose of vaccine is part of their complete primary vaccination schedule. They can then make a recall on medical advice. She is carried out one month after the 3rd dose.
Moderna or Pfizer: which vaccine for the 4th dose?
The booster dose for people aged 80 and over and all immunocompromised is done only with an mRNA vaccine, either Pfizer (30 µg dosage) or Moderna (50 µg dosage) regardless of the vaccine(s) previously used according to the COSV. The Pfizer vaccine is the only one recommended for people under the age of 30. “A full dose of Pfizer-BioNTech vaccine or a half dose of Moderna vaccine are used for this second booster shot” recommends the DGS.
What results in Israel?
Israel began on January 3, 2022 at inject a fourth dose”for people aged 60 and more, medical personnel and employees of health and social protection establishments“in addition to the immunocompromised persons concerned since December 31 according to the Ministry of Health from the country. According to Zvika Granot, an Israeli immunologist at the Hebrew University of Jerusalem quoted in the January 26 COSV advisory, “the initiative to start a fourth dose campaign [en israël] is not based on any clinical trial. There is no guarantee that it is safe“.”It is open to the most fragile, but it is not necessarily recommended (…). There are insufficient data regarding the efficacy and safety of this fourth dose.“, admitted Cyrille Cohen, immunologist at Bar-Ilan University in Tel Aviv (Israel), to franceinfo, January 3, 2022. The Sheba Hospital team initiated a planned 6-month clinical trial, vaccinating 154 caregivers with a fourth Pfizer dose and 120 other volunteers with a fourth Moderna dose. They had all received a third dose more than four months ago and the amount of their antibody seemed to have waned. The hospital said thatone week after the start of the clinical trialthe participants’ antibodies had increased fivefold. “However, we find that many people infected with Omicron have received the fourth dose. Admittedly, a little less but still a lot of infections“clarified Professor Gili Regev-Yochay, an expert in infectious diseases who is leading this study. According to the professor, “the bottom line is that the vaccine is great against Alpha and Delta but for Omicron it’s not good enough.”
Sources:
Vaccine Strategy Guidance Council Recommendations for the protection of severely immunocompromised people against Covid-19 (Vaccination and primary prophylaxis) – November 19, 2021
Launch of the vaccine booster campaign against Covid-19 for priority populations – DGS – August 27, 2021
Advisory Council for the Vaccine Strategy Opinion of August 19, 2021 – Minimum time between primary vaccination and booster vaccination