Can the vaccine prevent virus spread to the non-immune? Mucosal immunity and vaccines

Last week in The Pathfinder, I described the Systemic Immune System which mostly serves to protect internal organs and is activated by clinical infections of all sorts including the COVID virus and intramuscular vaccines such as the COVID vaccines. The larger “compartmentalized” mucosal immune system which is integral to the lining (mucosa) of the airways (from the nasal passages to the lungs) was also described.

When the airway is exposed to the airborne pathogen (like the COVID virus), the immune cells (lymphocytes) in the airway lining are activated and produce the protective antibodies whi...