Response to: COVID‐19 re‐infection. Vaccinated individuals as a potential source of transmission

Schiavone, Marco; Gasperetti, Alessio; Mitacchione, Gianfranco; Viecca, Maurizio; Forleo, Giovanni Battista

Vaccination against SARS-CoV-2 has shown to offer effective protection against Coronavirus disease (COVID-19) in persons 16 years of age or older in different trials [1,2], but its role against SARS-CoV-2 infection, determining subsequent positivity to real-time polymerase chain reaction (PCR) swab test is still unknown. Indeed, though being one of the greatest achievements reached by the scientific community in the last century, these trials did not address whether vaccinations succeeded to prevent asymptomatic infections. Only recently, plaque reduction neutralization testing was used to demonstrate that the BNT162b2 vaccine was capable to neutralize new highly transmissible SARS-CoV-2 variants with mutations in the S gene, detected in the United Kingdom (B.1.1.7 lineage), South Africa (B.1.351 lineage), and Brazil (P.1 lineage) [3]. Nevertheless, knowing if vaccination may as well prevent SARS-CoV-2 spreading is of the outmost importance especially among healthcare workers (HCWs), who are known to be at high risk of transmitting the viral disease in the hospital setting [4]. Cases of SARS-CoV-2 reinfections have been poorly described [5], but cases of swab test positivity after the vaccination have been often reported by mass media nowadays, along with concerns that vaccinated individuals could still transmit SARS-CoV-2 after COVID-19 vaccination [6]. Nevertheless, to date, no report that would at least sound scientific, is currently available. Hereby, we briefly report the first real-world case of positive PCR test in a HCW after full dose vaccination-induced immunity.