Researchers Find COVID-19 Shifting Toward an Endemic Phase

The World Health Organization declared the global health emergency related to the COVID-19 pandemic over in 2023, as most people had developed immunity against the virus through vaccination and/or prior infection.

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However, beyond 2023, the virus has continued to produce new variants capable of evading antibody responses and spreading worldwide. This trend may now be shifting in a more sustained manner.

Researchers studying infections at the German Primate Center – Leibniz Institute for Primate Research in Göttingen have reported that the most recently dominant variants are not being overtaken by a new, rapidly spreading global strain. Instead, a less typical variant, BA.3.2, is spreading at a comparatively slower rate.

This variant does not dominate in all countries but is frequently observed in infections among children. These findings indicate that a more complex immune landscape may have developed through vaccination and prior infections, making it more difficult for emerging variants to spread widely.

A New Pattern: From Rapid Replacement to Parallel Spread

Since 2020, new SARS-CoV-2 variants have appeared in quick succession, each replacing the previously dominant strains. However, this pattern may now be shifting. The most recently dominant variants, NB.1.8.1 and XFG, have not been succeeded, as expected, by a new globally dominant strain. Instead, the BA.3.2 variant, also known as “Cicada”, is spreading gradually but consistently.

BA.3.2, first identified in South Africa in November 2024, exhibits distinct characteristics: unlike earlier variants, it circulates alongside existing strains rather than replacing them. In parts of Europe and certain states in Australia, it has become dominant, while in other regions its spread has been more limited.

What Does This Mean for the Pandemic?

The researchers’ findings indicate a notable change: for the first time, a successful variant may not be overtaken by a new globally dominant strain; instead, several variants could circulate at the same time.

“This could indicate that the immune protection generated by vaccinations and previous infections is difficult for new variants to overcome,” explains Stefan Pöhlmann, lead author of the study.

The parallel spread of multiple variants could suggest that the infection dynamics are transitioning into an endemic phase - that is, a persistent presence of the virus in the population, in which globally synchronized waves of infection are no longer expected, but rather regional and temporally staggered outbreaks.

Stefan Pöhlmann, German Primate Center – Leibniz Institute for Primate Research

An Unexpected Observation: Children More Frequently Infected

BA.3.2 infects young children significantly more frequently than other types, according to an analysis of the relative infection frequency across age groups for currently circulating SARS-CoV-2 variants. The number of COVID-19 instances among youngsters has increased in Scotland and England, where the variant has spread widely, but the number of cases among older people has been constant. This odd preference's causes are still unknown.

The Significance of the Study

The German Primate Center's research provided fresh insight into the COVID-19 pandemic's dynamics. They contend that new variations can only partially overcome the worldwide protection created by vaccination and previous infections.

The international journal The Lancet Infectious Diseases published a commentary article with these findings and the researchers' evaluation of their importance.