Herd immunity is essential because it protects vulnerable populations, such as those with cancer, who cannot be vaccinated themselves.

“one of the things that has been happening is more and more parents of children with cancer are coming forward going online going on Facebook and so on and saying please vaccinate your children because my child's immune system has been devastated me and if your child is a carrier my child will die”

Relying on natural infection to reach herd immunity is a dangerous strategy that would result in a destabilizing loss of life.

“it's a horrible idea, exactly. And we do have alternatives, that's the important thing, we actually do have a way of controlling the disease, minimizing loss of life and reopening the economy”

Reaching herd immunity for SARS-CoV-2 will likely require at least 80 percent of the population to be immune through either vaccination or natural infection.

“there's a formula for this you would figure you that you probably would need at least 80 percent of the population to be immune either from natural infection or immunization to slow the the spread of this virus”