At a high level, the Moderna, Pfizer, and J&J vaccines are all giving instructions to our cells to produce one of the SARS-CoV-2 proteins, the spike protein. Our immune systems then learn to target that spike protein as foreign. When the SARS-CoV-2 virus hits us, the immune system is already prepared with the tools for defense. It attacks the spike protein and keeps you from getting sick, or at least from getting as sick as you would have if you weren’t vaccinated.

The Novavax is similar to more traditional vaccines in its technology, but it works along similar lines as the described COVID-19 vaccines. The key difference is the Novavax vaccine is the SARS-CoV-2 spike protein itself, not the instructions for how to make it.

It is just the protein—not a live or inactivated virus. The vaccine is relatively easy to distribute, because the cold chain requirements are not as strict as for the mRNA and adenovirus-vectored vaccines [such as the Moderna, Pfizer, and J&J vaccines]. If someone is allergic to the mRNA vaccines, they may not be to the Novavax, as it does not contain polyethylene glycol [an ingredient used as a stabilizing agent in some COVID-19 vaccines]. It appears to be highly effective against all the variants we’ve seen so far.

(As a side note, the Novavax vaccine is made using moth cells to generate the protein and tree bark for an ingredient to boost immune response. There are other vaccines based on particles derived from tobacco plants. Nature is an amazing thing, and I think we will find the work on vaccines over the last couple of years will allow science to solve problems that we couldn’t before.)