Source avec lien : Journal of Infection, (Prépublication). 10.1016/j.jinf.2021.08.031
Peu de données sont actuellement disponibles sur la cinétique des anticorps après vaccination avec des vaccins à ARNm dans leur ensemble et, avec l’ARNm-1273, en particulier. Nous rapportons ici une analyse ad-interim des données obtenues après un suivi de 6 mois dans une cohorte de travailleurs de la santé (TS) qui ont reçu le vaccin mRNA-1273. Ces nouvelles données permettent de mieux comprendre si et chez qui une 3ème dose pourrait être nécessaire.
Objectives Scarce data are currently available on the kinetics of antibodies after vaccination with mRNA vaccines as a whole and, with mRNA-1273, in particular. We report here an ad-interim analysis of data obtained after a 6-month follow-up in a cohort of healthcare workers (HCWs) who received the mRNA-1273 vaccine. These new data provide more insight into whether and in whom a 3rd dose could be necessary. Methods Our study compared the anti-S antibody kinetics at 2 weeks (T1), 3 months (T3) and 6 months (T4) after the first injection, and 2 weeks after the second injection (T2). The 201 participating HCWs were stratified according to their initial serological status. The vaccine effectiveness was also assessed through a medical questionnaire. Results We report here a marked and statistically significant antibody decrease (P < 0.05) between T3 and T4, especially in naïve vaccinees. The analysis of potential confounding factors or known risk factors for severe COVID-19 disease did not reveal any influence on the drop observed. Six-month after vaccination, only one, symptomatic, infection was reported in our cohort. Conclusions In a supply-limited environment, our results plead for reserving the 3rd dose scheme, in the upcoming months, to seronegative individuals prior to vaccination, especially when the serological status is easily accessible. Lisez l’article