This systematic review and meta-analysis aimed to compare the immunogenicity and safety
of an additional heterologous (viral vector) versus homologous (mRNA) COVID-19 vaccine …

Impaired response to COVID-19 vaccination is of particular concern in immunosuppressed
patients. To determine the best vaccination strategy for this vulnerable group we performed …

Conclusion There is still a need for COVID-19 vaccine strategies to evolve, not only to
provide better protection against infection and severe disease, but also to allow for more …

We aimed to evaluate the effectiveness or efficacy of heterologous or homologous COVID-
19 vaccine regimens against COVID-19-related outcomes after primary immunization with …

Objective To compare the efficacy of covid-19 vaccines between immunocompromised and
immunocompetent people. Design Systematic review and meta-analysis. Data sources …

Background The mass vaccination is a key strategy to prevent and control the coronavirus
disease 2019 (COVID-19) pandemic. Today, several different types of vaccines against …

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)-induced coronavirus
disease 2019 (COVID-19) has led to exponentially rising mortality, particularly in …

Background The immunogenicity of repeated vaccination and hybrid immunity in vulnerable
patients remains unclear. Methods We studied the impact of iterative Covid-19 mRNA …

Background Emergence of the SARS-CoV-2 omicron (B. 1.1. 529) variant with high immune
evasion has led to the development and roll-out of bivalent mRNA vaccines targeting …

Background Immunocompromised (IC) patients are at higher risk of severe SARS-CoV-2
infection, morbidity, and mortality compared to the general population. They should be …