When Will We Achieve Herd Immunity for COVID-19?

CLEVELAND – As COVID-19 vaccines are made available to more people across the country, we’re beginning to work toward herd immunity.

Frank Esper, MD, an infectious disease specialist with Cleveland Clinic Children’s said herd immunity happens when there’s enough protection in the community to prevent continued spread of the virus.

“When you see a high percentage of people who are immune to a germ, then that germ is not able to spread so quickly through the community,” he said. “It’s finding roadblocks because people are immune. If the virus comes to you and you have immunity against it, that’s a dead end for that virus. That virus has been blocked from spreading.”

Dr. Esper said vaccination is the best way to achieve herd immunity.

When people get a vaccine, he said they’re protecting themselves and the community, including those who can’t get the vaccine for medical reasons.

The number of people who need to be vaccinated to achieve herd immunity differs for each virus.

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.”

Dr. Esper said it will be several months before we see large numbers of people within communities who are immune to COVID-19.

In the meantime, vaccinated or not, it’s important to wear your mask, practice social distancing and wash your hands.