Scientific American – “Experts weigh in on common questions about whether and when additional doses of coronavirus vaccines may be needed…The groups it is clear should be getting additional doses include highly immunocompromised people: recipients of solid organ transplants, those with AIDS, those taking highly immunosuppressive drugs for cancer or autoimmune disease—these people have less of a response to vaccination. Some will respond to an extra dose but not all. Also, people in nursing homes, where we have seen breakthrough infections turn bad and lead to severe disease and death. Unvaccinated caregivers can introduce the virus to nursing homes. It makes sense to give additional doses to nursing home residents, but you would probably have a bigger impact giving them to caregivers. Beyond that, there’s really no clear data to support giving additional doses to the general public in the U.S. at this time…”