As other commenters have noted, this case study further supports the widespread observations that COVID-19 vaccines reduce the chance of severe (symptomatic) illness but do not necessarily prevent infection and transmission. The authors of this study conjecture that the unvaccinated asymptomatic “patient 40” may have been the source of the infections seen in the other fully vaccinated patients - however this was a mi…
EDIT: Before I get downvoted completely into oblivion, take a look at the 90% reduction in infections, both symptomatic and asymptomatic, seen in vaccinated individuals in Israel. https://pubmed.ncbi.nlm.nih.gov/33964222/
I think we can all agree that you can't transmit the virus if you yourself don't get infected.