top of page

COVID-19 timeline of herd immunity is currently unknown

By Alex Topor


The spread of COVID-19 could be basically eliminated with herd immunity but according to the Allegheny Health Department herd immunity is still a long way off.

Herd immunity is when a large portion of a community becomes immune to a disease, which makes person-to-person spread unlikely. This causes the entire community to become protected and not just those that are immune, according to

There are only two ways to achieve herd immunity – a vaccine or through the natural spread.

In a weekly press conference, Dr. Debra Bogen, director of the Allegheny County Health Department, said allowing the virus to spread naturally would be dangerous.

“The idea of letting this virus just go wild and let everyone get sick through natural spread is horrifying to me. We know if you compare it to influenza or H1N1 it is orders of magnitude more deadly,” Bogen said. “We don't know how much spread we would need for herd immunity at this point, but it’s a dangerous virus, especially for high-risk populations.”

If the virus is allowed to spread naturally in hopes herd immunity is reached it could overwhelm the nation’s medical system. According to, more than 200 million people would need to recover from COVID-19 for herd immunity to take effect.

This would also lead to millions of deaths, mostly of anyone considered high-risk.

The other option for herd immunity is through a vaccine. Vaccines lead to herd immunity without causing millions of illnesses and is how diseases such as smallpox and polio were contained, according to the Mayo Clinic. The downside to vaccinations is not everyone agrees with them and the disease could infect those that refuse a vaccine.

Though mass-vaccinations will likely be how the world moves past the COVID-19 pandemic, Bogen said vaccines are too far away for people to focus on them now. People should focus on social distancing and wearing masks to eliminate the spread of the coronavirus.

“I think it will be a couple months for high-risk groups to get a vaccine but a longer time for everyone else to be vaccinated. I don't want people to rely on herd immunity as a form of preventing the spread of the virus,” Bogen said. “We know this virus is dangerous and can make some people quite ill so we need to limit the spread as much as possible.”



bottom of page