Inspq Inspq Center of Expertise and Reference in Public Health A recommended reminder dose for certain groups

In the first opinion, the CIQ evaluates the relevance of offering a dose of recall to the oldest people who live in the community, like elders living in collective living environments (ex.: CHSLD and private residences for seniors) for whom a recommendation in this sense was issued on September 28.

Le second avis a pour objectif de décrire les données concernant l’efficacité des vaccins à vecteur viral (AstraZeneca/Covishield – Vaxzevria ou Johnson & Johnson) et à ARN messager (Pfizer – Comirnaty et Moderna – Spikevax) contre le variant delta du SRAS-CoV-2 et d’évaluer la pertinence d’offrir une dose de vaccin à ARN messager aux personnes ayant reçu uniquement des vaccins à vecteur viral contre la COVID-19.

Recommendations for the elderly

People aged 80 and over generally respond less to vaccines than young adults because of the phenomenon of immunoscence, a progressive alteration of the immune system linked to the age.Knowing that this group of people is the most vulnerable to the COVVI-19, the CIQ recommends providing them with a dose of recall with a vaccine with a minimum messenger RNA 6 months after the last dose received.

The CIQ also considers acceptable that people aged 70 to 79 take advantage of this possibility, but the benefit of a dose of recall appears less obvious at present, since vaccination efficiency is 85 % against infections and94 % against hospitalizations for this group.

Recommendation for viral vector vaccines

Le CIQ recommande que les personnes qui ont reçu uniquement le vaccin AstraZeneca ou Johnson & Johnson pour la série primaire (deux doses pour le vaccin d’AstraZeneca ou une dose pour celui de Johnson & Johnson) se voient offrir une dose de rappel de Pfizer ou Moderna, compte tenu de l’efficacité moins élevée des premiers.Indeed, the data indicates a superior response of viral vector vaccines when combined with a messenger RNA vaccine.The recall dose should be administered minimally 6 months after the last dose received.

The first two doses remain the priority

In general, the effectiveness of COVVI-19 vaccines is high.There is no sign of notable protection loss in Quebec and a dose of recall is not necessary at the moment for the vast majority of the population.The priority is to receive the first two doses of the vaccine.