I just read that many were sick of covid or whatever, given the pcr fraud, on a fully vaccinated cruiseship. However, what they're possible shedding would possibly be the viral spike protein their bodies are manufacturing.

The study authors’ theory hinges on the hypothesis that the vaccinated are transmitting protective antibodies through the air.

Antibodies? No spike protein, no mRNA, no virus, no exosomes or whatever, but antibodies? Antibodies don't induce an immune response, they are the immune response.