A contagious novel coronavirus may have very little to do with the massive deaths of medically fragile patients in nursing homes, imo. Some time ago I picked up a copy of a book about the crisis in American nursing homes.
If you load many fragile patients into homes that are already short on staff and deny family visits, I think deaths would be inevitable. Flu shots increase the risk of some types of respiratory illnesses such as coronavirus. Staff and residents of nursing homes receive flu shots every year.