How Long Until Full Immunity After Being Vaccinated?

President Joe Biden has recently said that by May 1, 2021, everyone 18 or older will be eligible to receive the vaccine. With three vaccines currently on the market in the United States—Pfizer, Moderna and Johnson & Johnson, the question that now remains is how long until full immunity is reached once one has been inoculated?

In regards to the Pfizer and Moderna vaccines, two doses are required. This means that only partial immunity is reached when you receive the first dose and after the second dose there is a window of time before full immunity is reached. That second dose kicks everything into gear and prepares your body if real-life infection occurs.

The reason behind the need for two doses with Pfizer and Moderna is because during the early stages of testing, researchers found that the vaccines did not produce a very strong immune response after the first dose. To combat this, they added a second dose and observed the reactions, thus leading to the high efficacy rate of both of these vaccines; the second dose acts as a reinforcement to the first dose.

With this in mind, it takes about 10 to 14 days after receiving the second dose of both two dose vaccines to reach full immunity. Dr. Fauci stated a “10-fold increase in neutralizing antibodies,” after this interval.

Researchers are still studying if there is an effect in waiting too long to get your second dose of the two dose vaccines, overall, their hypothesis is that the vaccine effect is lowered. The FDA recommends sticking to the schedule of your vaccine and receiving it within the required time, however the CDC recommends not waiting any longer than 6 weeks.

Johnson & Johnson’s vaccine is different from the other two vaccines on the market—only requiring one dose to reach full immunity after 28 days. But this does not mean that the time needed to build up that immunity is different, in fact, the time it takes to reach full immunity with the one dose of the Johnson & Johnson vaccine is almost equivalent to the total time needed to reach full immunity by the time one has had both doses of Pfizer or Moderna.

The common side effects you can expect to experience when you receive the shot include: pain, redness and swelling where the shot was administered. Throughout your body, you can expect to feel tiredness, headaches, muscle pain, chills, fever and nausea. In order to reduce these effects, talk to your doctor about using over-the-counter medications like ibuprofen, acetaminophen, aspirin, or antihistamines after getting vaccinated and use a cool, wet washcloth on the arm that was inoculated, as well as keeping it mobile. If arm redness or tenderness last any longer than 24 hours or you side effects become severe or remain after a few days, seek medical attention.