A related question seems to keep popping up: How long after receiving the second COVID dose are you immune, or fully protected, against the virus? “Regardless of which vaccine you get, you won’t reach full protection until two weeks after your second or final dose. That’s about how long it takes your immune system to mount an antibody response to the vaccine.”AdRemember, three vaccines are currently being distributed: Moderna, Pfizer and Johnson & Johnson. The first two require two doses -- and Johnson & Johnson is the only one that’s just a single dose. This is why the second dose is so important, and why we’re so diligent about scheduling you for your follow-up shot.”AdDon’t skip that second dose.