Did you miss your appointment to get the second dose of the Covid-19 vaccine, like the deserts miss the rain? Well, don’t panic. Panic is never the answer to anything, except perhaps the question, “what should you never do?”
First of all, double-check what type of vaccine you got for the first dose. If it was the Johnson & Johnson Covid-19 vaccine then you should be set for now. One dose of this vaccine is all that you’ll need to be considered “fully vaccinated” two weeks afterwards and beyond. So put on your unitard or whatever you typically wear to celebrate and grab yourself a slice of cheesecake.
If the first dose was the Pfizer/BioNTech or Moderna Covid-19 mRNA vaccine then you need a second dose of the same vaccine. Don’t be among the 8% or so of people who are skipping the second dose of the Covid-19 mRNA vaccine. While the first dose should offer some degree of protection, it won’t give you nearly the same degree of protection. In fact, with only one dose, protection against Covid-19 coronavirus infection may be only about half (46% versus 92%) of what it could be after two doses, according to a study from Israel published in the New England Journal of Medicine. Moreover, a single dose may still leave you very vulnerable to the B.1.351 variant of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), the one that first emerged in South Africa. Anthony Fauci, MD, Director of the National Institute of Allergy and Infectious Diseases (NIAID), reviewed some of this data in the video accompanying the following tweet:
When you got your first dose of the mRNA vaccine, you were probably scheduled for a second dose three weeks for the Pfizer/BioNTech vaccine or four weeks for the Moderna vaccine later. However, life happens. Maybe you were caught at work. Maybe you were celebrating National Lumpy Rug Day. Maybe you or someone around you got sick. Or maybe you just forgot. Don’t worry. There is some leeway. Try to get the second doses as soon as possible after the originally scheduled date. According to the Centers for Disease Control and Prevention (CDC), as long as you get the second dose within 42 days of the first dose, everything’s cool.
Beyond 42 days is a different story. It’s not as if things change dramatically 42 days and one second after you got the first dose. Your body is not like a Hot Pocket, where minutes and even seconds can make a difference. Nonetheless, when go more than seven weeks after the first dose, you enter the question mark zone. There just isn’t data on how much protection a booster dose will give you when the priming dose (i.e., the first dose) was eight, nine, or more weeks prior. Will your immune system be like that person you met a while ago and forgot to call until now? (Isn’t the dating rule wait two days and not two months to call someone?) That is, will your immune system see the spike protein generated by the second dose and say, “what is this? I don’t remember this?” Or will the immune system still have enough memory from the first dose to muster enough protection?
Regardless, even if you are more than seven weeks past the first dose, get the second dose as soon as you can. Remember the song “Two Beavers are Better Than One” from the television series How I Met Your Mother? Well, the same applies to Covid-19 mRNA vaccines, even when they are spaced a bit too far apart.