Virological characteristics of SARS-CoV-2 vaccine breakthrough infections
medrxiv.org
medrxiv.org
Important finding:
"Despite similar Ct-values, we demonstrate lower probability of infectious virus detection in respiratory samples of vaccinated HCWs with breakthrough infections compared to unvaccinated HCWs with primary SARS-CoV-2 infections.
Nevertheless, infectious virus was found in 68.6% of breakthrough infections and Ct-values decreased throughout the first 3 days of illness."
We conclude that rare vaccine breakthrough infections occur, but infectious virus shedding is reduced in these cases.