Does Ómicron bring us closer to herd immunity against COVID-19?

Experts say this highly transmissible variant, or any other, is unlikely to lead to herd immunity.

“Herd immunity is an elusive concept and does not apply to coronavirus,” said Dr. Don Milton of the University of Maryland School of Public Health.

This type of immunity occurs when a sufficient percentage of the population is immune to a virus, complicating its spread among those not protected by a vaccine or previous infection.

For example, in the case of measles, it takes about 95% of the community to reach it. Initial hopes of achieving herd immunity against the coronavirus have been dashed for several reasons.

One is that antibodies developed from available vaccines or infection decline over time. Although vaccines offer strong protection against a severe case of the disease, the drop in antibodies means that infection is possible even for those who have a third booster dose.

In addition, there is a wide disparity in the vaccination rate: in some resource-poor countries, less than 5% of the population is vaccinated; wealthy nations face resistance from the population to them and, in many places, they are not authorized for young children.

The virus mutates as it spreads, which helps it survive and encourages the emergence of new variants. These mutations, such as omicron, may be better at evading protection provided by vaccines or previous infection.

Milton said that the population is moving towards “herd resistance,” which occurs when infections continue, but there is enough protection so that future outbreaks are not as disruptive to society.

Many scientists believe that COVID-19 will eventually become a disease like the flu, with seasonal outbreaks but not large waves of infection.