COVID-19 Breakthrough Infections in Vaccinated Individuals

COVID-19 Breakthrough Infections


  • Antonis S Manolis First Department of Cardiology, Athens University School of Medicine, Athens, Greece
  • Theodora A. Manolis Aghia Sofia University Hospital, Athens


Vaccine breakthrough COVID-19 infections are increasingly occurring in fully vaccinated individuals, who may also spread COVID-19 to others. Hence, one is better protected if one wears a mask and maintaining distancing when in indoor public places. Mild infections pose little risk to vaccinated individuals and their contacts, while they may boost the individual immune responses and thus necessitate only monitoring as a precautionary measure. However, higher infectiousness and transmissibility of viral variants remain worrisome. Variants of concern are overrepresented among post-vaccination breakthrough COVID-19 infections. Identifying subgroups at a high risk for severe breakthrough infections is important in prioritizing early preventive treatment or prophylaxis. Despite a strong protection afforded by vaccination against severe disease, breakthrough infections may still advance to severe or critical illness at not-insignificant rates. The age distribution of patients with severe breakthrough infections is skewed towards older age groups and individuals with underlying comorbidities. All these issues and factors modulating the probability of a breakthrough COVID-19 infection in vaccinated people are herein discussed, and a tabulated list of the recommendations of the World Health Organization on COVID-19 infection prevention and control is also presented. Rhythmos 2022;17(1): 92-99.