"Why Mucosal Immunity May Be Necessary to Stop the Pandemic"
This is a sobering reminder of how hard it's going to be to get this under control.
Mucosal immunity protects the parts of the body that are in contact with the environment, and in the case of a respiratory pathogen, that means the nasal cavity and the lungs. Because it is a localized type of response, a vaccine needs to be delivered to the appropriate compartment if mucosal immunity is to be stimulated. In the case of a respiratory pathogen like SARS-CoV-2 that means intranasal vaccine administration.
Without mucosal immunity, the virus may continue to thrive in a person’s nasal cavity allowing for easy transmission. This is why wearing a mask, even after vaccination with an intramuscular vaccine, will remain critical.