2023 witnessed several changes in COVID-19 variants, health policies, and vaccines. As year three of the world affected by COVID-19 ends, we reflect on the advances, changes, and lessons learned.
Over the past three years, COVID-19 has changed, creating variants. Variants occur when viruses infect cells and reproduce. Sometimes, these duplicates contain errors that make changes in the virus’s DNA. The errors can be more effective at spreading or evading current vaccines.
Omicron, a variant of COVID-19, continues to produce sub-variants. Earlier this year, public and other health professionals closely watched variants, including BA.2.86. Late summer/early fall saw the emergence of another variant named JN.1. At first, JN.1 compromised a small portion (0.01%) of new cases being reported. The Centers for Disease Control and Prevention (CDC) announced in December that JN.1 is estimated to comprise 15-29% of reported COVID-19 cases. Furthermore, the CDC predicts JN.1 cases will continue to rise as the holiday season and winter continues.
CDC officials believe the growth of JN.1 hints that the variant is either better at evading the immune system or is highly transmissible. However, CDC professionals do not see evidence that JN.1 increases the risk to public health. Or that updated COVID-19 vaccines are less effective against JN.1.
Immunocompromised people are at an increased risk of contracting COVID-19. However, they are also at a higher risk of creating new variants of COVID-19. A study published in The Journal of Infectious Diseases reported immunocompromised people with prolonged infection of COVID-19 have SARS-CoV-2 organisms with “higher genetic diversity.” The increased diversity may cause the development of new variants.
Updated COVID-19 vaccines were introduced in the fall. The CDC recommends the latest (2023-2024) COVID-19 vaccines produced by Pfizer-BioNTech, Moderna, or Novavax. The updated vaccines address the latest variants of COVID-19, including BA.2.86 and its closely related variant JN.1. The CDC recommends:
Researchers studying the effects of mRNA-1273 on COVID-19 published their findings in Open Forum Infectious Diseases. The researchers compared the effects of COVID-19 vaccines on a control group and a group given the mRNA-1273 vaccine. The results found the incidence rate of COVID-19 was higher among the control group.