The Centers for Disease Control and Prevention’s latest Covid guidelines have many Americans confused. Vaccinated people are supposed to resume wearing masks, lest they contract and spread the virus. [SNIP] The answer is that there’s more than one kind of immunity. Internal immunity protects the inside of the body, including the lungs. This occurs by release of antibodies of the Immunoglobulin G type, or IgG, into the blood and production of T-cells. Vaccines injected into our muscles are highly effective at stimulating internal immunity. This largely protects vaccinated people from being overwhelmed by the coronavirus, unless they have an immunodeficiency...