“ Vaccines need updates as the virus evolves ”

Berlin: Scientists have assessed the course of evolution of the new coronavirus and predicted that COVID-19 vaccines currently in use around the world may require regular updates to counter new variants of the virus capable of escaping protective antibodies from the body.

The study, published in the journal Virus Evolution, assessed whether, in the long term, the SARS-CoV-2 virus is likely to demonstrate an immune evasion capacity comparable to that of influenza viruses.

As part of this research, virologists from Charite – Universitatsmedizin Berlin in Germany studied the genetic evolution of the four currently known “ common cold ” coronaviruses, in particular the two oldest viruses, 229E and OC43.

They tracked the changes in the spike protein of these coronaviruses, which allow them to enter host cells, around 40 years ago.

Based on the analysis, scientists found a feature common to both the coronavirus and the influenza virus: All three had a pronounced ladder-like shape in their evolutionary trajectories.

“An asymmetric tree of this type is likely the result of the repeated replacement of one variant of the circulating virus with another that had a fitness advantage,” said study first author Wendy K. Jo.

According to Jo, this is evidence of “antigenic drift,” an ongoing process involving changes in surface structures that allow viruses to evade the human immune response.

“This means that these endemic coronaviruses also elude the immune system, just like the influenza virus. However, one also has to look at the rate at which this evolutionary adaptation occurs,”

she added.

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