I've read the article:
regarding a prospective method of immunization against sars-cov-2 using the spike protein of the virus and micro-needle array delivery (MNA) and I've wondered if using the virus instead of the spike protein makes sense. What are the trade-offs? Is the risk of the virus spreading through the bloodstream in the body very high? Is culturing the virus or producing the spike protein more expensive? Can the sars-cov-2 virus be de-activated after being produced to make it safer?