I'm thankful that the few friends who have tested positive have described their symptoms as flu like. None hospitalized. Half testing positive before vaccines were available. I can't recall many vaccines that have been 100% effective at eradicating a virus. Flu, hepatitis, measles, chickenpox and many others have vaccines that may not provide complete protection. Eventually those that have an immune system that can survive this particular one will state the vaccine is effective, when in all probability, those that are susceptible will have died.