https://blogs.sciencemag.org/pipeline/archives/2020/04/15/coronavirus-vaccine-prospects https://blogs.sciencemag.org/pipeline/archives/2020/04/15/co... Doesn't

https://blogs.sciencemag.org/pipeline/archives/2020/04/15/coronavirus-vaccine-prospects https://blogs.sciencemag.org/pipeline/archives/2020/04/15/co... Doesn't answer your question but hints at the complexity.