Antibody response to SARS‐CoV‐2 vaccination is extremely vivacious in subjects with previous SARS‐CoV‐2 infection

Abstract

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic calls for rapid actions, now principally oriented to a world-wide vaccination campaign. In this study we verified if, in individuals with a previous SARS-CoV-2 infection, a single dose of messenger RNA (mRNA) vaccine would be immunologically equivalent to a full vaccine schedule in naïve individuals. Health care workers (184) with a previous SARS-CoV-2 infection were sampled soon before the second dose of vaccine and between 7 and 10 days after the second dose, the last sampling time was applied to SARS-CoV-2 naïve individuals, too. Antibodies against SARS-CoV-2 were measured using Elecsys Anti-SARS-CoV-2 S immunoassay. The study was powered for non-inferiority. We used non parametric tests and Pearson correlation test to perform inferential analysis. After a single vaccine injection, the median titer of specific antibodies in individuals with previous coronavirus disease 2019 was 30.527 U/ml (interquartile range [IQR]:19.992-39.288) and in subjects with previous SARS-CoV-2 asymptomatic infection was 19.367.5 U/ml (IQR: 14.688-31.353) (p = .032). Both results were far above the median titer in naïve individuals after a full vaccination schedule: 1974.5 U/ml (IQR: 895-3455) (p < .0001). Adverse events after vaccine injection were more frequent after the second dose of vaccine (mean: 0.95; 95% confidence interval [CI]: 0.75-1.14 vs. mean: 1.91; 95% CI: 1.63-2.19) (p < .0001) and in exposed compared to naïve (mean: 1.63; 95% CI: 1.28-1.98 vs. mean: 2.35; 95% CI: 1.87-2.82) (p = .015). In SARS-CoV-2 naturally infected individuals a single mRNA vaccine dose seems sufficient to reach immunity.Modifying current dosing schedules would speed-up vaccination campaigns.

MENACTRIMS practice guideline for COVID-19 vaccination in patients with multiple sclerosis

“… If a patient had COVID-19 and recovered, he/she should also get the vaccine, because prior infection does not appear to protect from future COVID-19 infection indefinitely. However, recent studies [ Callegaro et al, 2021 , Malek et al, 2021 , Amit et al, 2021 , Pawlowski et al, 2021 ] have shown that a single dose of the mRNA vaccines might provide adequate immunity in previously infected patients. Even if vaccinated, patients with MS should continue to take precautions against COVID-19, such as wearing a face mask, social distancing and washing hands.…”

Prospective Observational COVID-19 Screening and Monitoring of Asymptomatic Cancer Center Health-Care Workers with a Rapid Serological Test

“…On the contrary, to the best of our knowledge, no specific information concerning the utilization of rapid serological testing to monitor vaccinated subjects is available. On the other hand, a recent study conducted on vaccinated HCWs, via the use of a qualitative-semiquantitative electrochemiluminescence serological test, showed that COVID-19 positive HCWs had a single dose antibody titer ten times higher than that of naïve HCWs with a full vaccination schedule [21].…”

Previous SARS‐CoV‐2 infection is linked to lower vaccination intentions

“…In their recent communication, Callegaro et al 1 could show that mRNA vaccination boosts antibodies elicited by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infections. 1 Thus, vaccinating not only uninfected but also previously infected individuals could become important for controlling the pandemic.…”

“…In their recent communication, Callegaro et al 1 could show that mRNA vaccination boosts antibodies elicited by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infections. 1 Thus, vaccinating not only uninfected but also previously infected individuals could become important for controlling the pandemic. We investigated the vaccination intentions of previously infected, recovered individuals using data from seven cross‐sectional, quota‐representative surveys 2 with N = 5692 nonvaccinated German participants, conducted between February 23 and May 19, 2021.…”