Experts: Reopening states still far from herd immunity

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Posted at 7:16 PM, Jun 03, 2021

CINCINNATI — Masks are coming off in Ohio, Kentucky and Indiana, thanks to widespread availability of the COVID-19 vaccine and politicians’ increasing willingness to let unvaccinated people roll the dice on their own health.

But none of the three states — nor any state in the country — has achieved a high enough level of vaccination to reach “herd immunity,” a situation in which the novel coronavirus can no longer spread because its supply of vulnerable hosts is too small.

Experts estimate herd immunity occurs when a population is 70-90% vaccinated. In Ohio, the most-vaccinated state of the three, only about 40% of people have gotten all their COVID-19 shots.

University of Cincinnati professor Dr. Carl Fichtenbaum said any amount of vaccination is helpful in preventing the novel coronavirus from spreading, but unvaccinated people are still in danger as social gatherings and indoor events resume.

“The people we’re seeing in the hospital are those who’ve never been vaccinated,” he said.

And it might be difficult to gauge the true danger until fall, Fichtenbaum added. In summer, all people are more likely to be socializing and attending events outdoors — where COVID-19 transmission is much more uncommon, even for unvaccinated people.

“We see a lot more spread when people are indoors,” he said.

Fall might be the first real test for a post-vaccine society. In the meantime, Fichtenbaum said, he and other experts will look closely at case numbers after Fourth of July gatherings.