Stability of hybrid versus vaccine immunity against BA.5 infection over 8 months

© 2022 Elsevier Ltd. All rights reserved. The coverage of SARS-CoV-2 vaccination in large parts of the world, together with the high number of breakthrough infections, especially following the emergence of Omicron subvariants, makes hybrid immunity (resulting from vaccine and infection) common. Hybrid immunity, particularly after BA.1 or BA.2 infection, confers substantial protection against the BA.5 infection. However, although the waning of protection afforded by natural infection in non-vaccinated individuals or by vaccination has been well documented, the stability of hybrid immunity, specifically against the BA.5 subvariant, now dominant in many countries, has not been thoroughly addressed.