Topic: Nasal Immunity

AstraZeneca launched a home-delivery service for FluMist, a nasal spray flu vaccine available for individuals aged 2 to 49. Dr. Tara Narula explained that the vaccine is not recommended for those over 49 because older immune systems may not respond effectively to the live, weakened virus. The hosts used an AI assistant to clarify the risks and joked about being "friend-zoned" by the digital bot during the inquiry.

NPR science correspondent Joe Palca reports on leaked CDC documents suggesting the Delta variant is as contagious as chickenpox. Palca presents a theory regarding "local immunity," claiming the Delta variant replicates specifically in the nose and throat of vaccinated individuals, allowing them to transmit the virus despite systemic protection. Critics argue this localized infection theory lacks medical consensus and serves as a narrative shift to explain vaccine breakthrough cases.