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Coronaviruses

COVID-19 Vaccines May Need Periodic Updates to Stay Effective

Strategic Insights

— 2 min read

Researchers at the Fred Hutchinson Cancer Research Center investigated the evolution of human coronavirus 229E and found that it accumulates mutations that escape neutralization by antibodies, suggesting that coronavirus vaccines may need to be periodically updated to keep pace with viral evolution. The study published in PLoS Pathogens in April 2021, found that the rate at which viral evolution degrades immunity varies among individuals, but in some cases, less than a decade of evolution is sufficient to completely eliminate neutralization by human sera that is potent against contemporaneous viruses.

Key Takeaways:

  • The study found that human coronavirus 229E accumulates mutations that escape neutralization by antibodies, suggesting that coronavirus vaccines may need to be periodically updated to stay effective.
  • The rate at which viral evolution degrades immunity varies among individuals, but in some cases, less than a decade of evolution is sufficient to completely eliminate neutralization by human sera that is potent against contemporaneous viruses.
  • The study identified human sera from the 1980s and 1990s that have neutralizing titers against contemporaneous 229E that are comparable to the anti-SARS-CoV-2 titers induced by SARS-CoV-2 infection or vaccination.
  • The study found that neutralizing titers are lower against 229E strains isolated after sera collection, and in some cases, sera that neutralize contemporaneous 229E viral strains with titers 1:100 do not detectably neutralize strains isolated 8-17 years later.
  • The decreased neutralization of 'future' viruses is due to antigenic evolution of the viral spike, especially in the receptor-binding domain.
  • The study suggests that it may be advisable to periodically update SARS-CoV-2 vaccines if these results extrapolate to other coronaviruses.

Statistics:

  • The study used sera from the 1980s and 1990s to test the evolution of human coronavirus 229E.
  • The sera had neutralizing titers against contemporaneous 229E that are comparable to the anti-SARS-CoV-2 titers induced by SARS-CoV-2 infection or vaccination.
  • In some cases, less than a decade of evolution is sufficient to completely eliminate neutralization by human sera that is potent against contemporaneous viruses.
  • The study found that the receptor-binding domain of the viral spike is particularly susceptible to mutations that escape neutralization by antibodies.
  • The study suggests that SARS-CoV-2 vaccines may need to be updated periodically to keep pace with viral evolution.

Sources:

  • A Human Coronavirus Evolves Antigenically To Escape Antibody Immunity. PLoS Pathogens, 2021;17(4). PLoS Pathogens can be contacted at: Public Library Science, 1160 Battery Street, Ste 100, San Francisco, CA 94111, USA. (Public Library of Science - www.plos.org; PLoS Pathogens - www.plospathogens.org)
  • Jesse D. Bloom, Fred Hutchinson Cancer Research Center, Basic Sci & Computat Biol, 1124 Columbia St, Seattle, WA 98104, United States.

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