Vaccine Data

Bloomberg: Covid-19 Tracker

Why 75% for herd immunity?

The 75% herd immunity marker was chosen based on consensus of public health officials opinions from around the world. This number does not include confirmed cases and previously infected individuals. It also does not take into account the effectiveness of the vaccine on new COVID-19 variants. The number could be adjusted once more data becomes available.

Opinions we sourced:

Frank Esper, MD - Infectious Disease Specialist, Cleveland Clinic Children’s Hospital

For coronavirus, he believes 70-90% of the population will need to be vaccinated to maintain protection, although scientists are still trying to determine exact numbers.
“As more and more people get that immunity, the spread of the virus is going to slow and slow,” said Dr. Esper. “Eventually, we hope that it’s going to get to the point where we get this herd immunity. There will not be continuous infection and we will only see intermittent isolated infections from then on out.”

Source: When will we achieve herd immunity for COVID-19

Dr. Chirag Patel - UF Health Jacksonville

What herd immunity is, is when people in the population develop immunity to a specific disease or pathogen, or in this case, a virus and that in of itself will significantly limit the ability of that virus to spread because, if enough people in the community are immune to it, the virus really has no place to jump. It can’t go person to person,” Patel explained. “What we are seeing here and there are different estimates, on the conservative side we think about 70% of the population needs to have immunity to achieve herd immunity. Some have argued that with the mutations that are occurring now, it’s going to take 90% herd immunity to happen.

Source: Health experts estimate at least 70% of population needs to be immune to virus to achieve herd immunity

Dr. Anthony Fauci - Director, NIH

If we get 70% to 85% of the country vaccinated, let's say by the end of the summer, middle of the summer, I believe by the time we get to the fall we will be approaching a degree of normality.

Source: Fauci: Vaccinations will help coronavirus variants from emerging

Dr. Soumya Swaminathan - Chief Scientist, WHO

So, the SARS-CoV-2 virus is a highly transmissible virus. We think it needs at least 60 to 70% of the population to have immunity to really break the chain of transmission. If you allow this to happen naturally, it will take a long time, of course, but more importantly, it's going to do a lot of collateral damage. So even if 1% of people who get infected are ultimately going to die, then this can add up to a huge number of people, if we look at the global population. And that is why we believe it's not a good idea to try to achieve herd immunity by just letting the infection run wild in the population and infect a lot of people and that we should talk about herd immunity in the context of a vaccine.

Source: Episode #1 - Herd immunity