Vaccine Confident mark
An initiative to help pharmacists strengthen vaccine confidence in their patients and communities
How to talk to people about COVID-19 vaccines Addressing concerns that the COVID-19 vaccines were “rushed” Addressing concerns about COVID-19 vaccine side effects Addressing concerns related to pregnancy, breastfeeding, and fertility Addressing concerns related to religious beliefs Addressing the belief that COVID-19 vaccination is “not needed” Addressing COVID-19 vaccine myths Understanding the “system distrusters” Understanding the “COVID skeptics” Understanding the “cost anxious” Addressing concerns about SARS-CoV-2 variants Addressing concerns about COVID-19 breakthrough infections Addressing COVID-19 vaccine misinformation and disinformation Identifying credible information about COVID-19 Vaccines Addressing concerns about covid-19 vaccine boosters Addressing COVID-19 vaccine misunderstandings How to restart the vaccine conversation Addressing concerns about administering COVID-19 vaccines with other vaccines Addressing concerns about vaccinating children and teens Addressing concerns of people who are immunocompromised

Addressing concerns about SARS-CoV-2 variants

Note: While this section was written with COVID-19 vaccines in mind, many of the general principles apply to other vaccines as well. Individual vaccines may vary in their antigenic components or dosage forms, but the principles of human behavior and good communication skills transcend most differences between vaccines.

The Issue

SARS-CoV-2—the coronavirus that causes COVID-19—was first identified in China in December 2019. Since then, multiple variants of the virus (SARS-CoV-2) have been identified around the globe. Some people may be concerned about the ability of COVID-19 vaccines to protect against emerging variants. Others may view media reports of breakthrough infections as evidence of the limitations of COVID-19 vaccines and question the need to be vaccinated (i.e., an additional reason not to get a COVID-19 vaccine).

This section provides a general discussion of COVID-19 variants. For more details, see:

Sound Bites

  • Many viruses—including SARS-CoV-2, the virus that causes COVID-19—change over time through repeated mutation. A virus with one or more new mutations is referred to as a “variant” of the original virus.As expected, multiple variants of SARS-CoV-2 have been documented throughout the COVID-19 pandemic.
  • The best way to slow the emergence of new variants is to reduce transmission (i.e., slow the spread of infection). The best way to reduce transmission is to get vaccinated against COVID-19 and follow guidance for masking and physical distancing.
  • Receiving COVID-19 vaccination reduces your risk of severe illness, hospitalization, and death from COVID-19. Staying up to date on your COVID-19 vaccines further improves your protection.

What We Know

Many viruses evolve over time. SARS-CoV-2, the virus that causes COVID-19, is no exception.

Viruses constantly change through mutation when they replicate. A virus with one or more new mutations is referred to as a “variant” of the original virus. Virus variants are both expected and normal.

Many variants emerge and then disappear. In some cases, new variants persist; they survive better than, and can outcompete, the original virus. At this point in the pandemic, the original virus that caused the initial COVID-19 cases in December 2019 is no longer circulating. Some variants appear to spread more easily and quickly than other variants, which may lead to more cases of COVID-19.

The World Health Organization (WHO) has been working with its partners, expert networks, national authorities, institutions, and researchers since 2020 to monitor and assess the evolution of SARS-CoV-2.1 Emerging variants are named using letters of the Greek alphabet to make public discussion easier. SARS-CoV-2 variants also may be referred to by various technical nomenclature systems   .

Both WHO and the U.S. government SARS-CoV-2 Interagency Group (SIG) use a variant classification scheme that defines three classes of SARS-CoV-2 variants:1,2

  • Variants of Interest.
  • Variants of Concern.
  • Variants of High Consequence.

Variants are classified based on how easily they spread, how severe their symptoms are, and how they are treated (e.g., Are existing treatments and vaccines effective against the variant?). The U.S. government SIG classifications may differ from WHO classifications because the importance of variants may differ by location. The Centers for Disease Control and Prevention follows the changing frequency of variants in the United States.2

A SARS-CoV-2 Variant of Interest has specific genetic markers associated with changes to receptor binding, reduced neutralization by antibodies generated against previous infection or vaccination, reduced efficacy of treatments, potential diagnostic impact, or predicted increase in transmissibility or disease severity.

A SARS-CoV-2 Variant of Concern shows evidence of an increase in transmissibility, more severe disease (e.g., increased hospitalizations or deaths), a significant reduction in neutralization by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures.

A SARS-CoV-2 Variant of High Consequence has clear evidence that prevention measures or medical countermeasures have significantly reduced effectiveness relative to previously circulating variants.

Throughout the various surges of specific variants, the COVID-19 vaccines were highly effective in reducing the risk of severe illness, hospitalization, and death.3 Data from Los Angeles County, California, showed that during both Delta and Omicron predominance, COVID-19 incidence and hospitalization rates were highest among unvaccinated persons and lowest among vaccinated persons with a booster.4 The data for hospitalization were particularly striking. Unvaccinated persons were 23 times more likely to be hospitalized than fully vaccinated persons with a booster. They were 5.3 times more likely to be hospitalized than were vaccinated persons without a booster.

References

  1. World Health Organization. Tracking SARS-CoV-2 variants. Updated April 11, 2024. Accessed April 12, 2024. https://www.who.int/en/activities/tracking-SARS-CoV-2-variants/
  2. Centers for Disease Control and Prevention. SARS-CoV-2 variant classifications and definitions. Updated September 1, 2023. Accessed February 25, 2024. https://www.cdc.gov/coronavirus/2019-ncov/variants/variant-classifications.html
  3. Tenforde MW, Self WH, Gaglani M, et al. Effectiveness of mRNA vaccination in preventing COVID-19–associated invasive mechanical ventilation and death—United States, March 2021–January 2022. MMWR Morb Mortal Wkly Rep. 2022;71(12):459–465. doi: 10.15585/mmwr.mm7112e1
  4. Danza P, Koo TH, Haddix M, et al. SARS-CoV-2 infection and hospitalization among adults aged ≥18 years, by vaccination status, before and during SARS-CoV-2 B.1.1.529 (Omicron) variant predominance—Los Angeles County, California, November 7, 2021–January 8, 2022. MMWR Morb Mortal Wkly Rep. 2022;71(5):177–181. doi: 10.15585/mmwr.mm7105e1

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