The genome of Covid-19 was mapped in early Feb. The gene for a protein spike was used to produce these spike proteins. 3-D microscopy of this synthesized spike has been produced. Quoting McLellan from this article:
"the molecule looks really good; it's really well behaved; the structure kind of demonstrates that the molecule is stable in the correct confirmation that we were hoping for," McLellan said. "So now we and others will use the molecule that we created as a basis for vaccine antigen."
In theory, the spike protein itself "could be either the vaccine or variants of a vaccine," McLellan said. When you inject this spike-protein-based vaccine, "humans would make antibodies against the spike, and then if they were ever exposed to the live virus,"
The article goes on to say:
Their colleagues at the NIH will now inject these spike proteins into animals to see how well the proteins trigger antibody production. Still, McLellan thinks a vaccine is likely about 18 to 24 months away. That's "still quite fast compared to normal vaccine development, which might take like 10 years," he said.
My question is: Why not inject, or drink, these spike proteins for immunity to Covid-19? Why expect an 18-24 month wait? The anti-body production response should occur(and be detectable) in days?