Viruses are constantly changing, and every time they replicate there is a chance that a mutation will be introduced. The novel coronavirus (COVID-19) is no different.
These mutated viruses are called variants. Most viral variants behave similarly to the original form of the virus, but others can behave very differently.
Viral variants may be classified by the World Health Organization (WHO) as variants under investigation (VUI), variants of interest (VOI), or variants of concern (VOC). VOCs may be associated with the ability to spread more quickly in people, the ability to cause more severe disease, the ability to evade detection by viral diagnostic tests, decreased susceptibility to therapeutic agents, or the ability to evade natural or vaccine-induced immunity.
Multiple variants of the virus that causes COVID-19 — severe acute respiratory distress syndrome coronavirus 2 (SARS-CoV-2) — have been documented over the course of the pandemic.
There are currently five variants of concern for SARS-CoV-2 in the United States, including the “British variant” — known officially as B.1.1.7. The variant was first detected in the UK during September 2020 and has now been identified in over 30 countries, including the US, in December 2020. (1)
According to the CDC, there are 812 documented cases of COVID-19 caused by the British variant in Tennessee. (2) The variant is associated with increased ease of transmission and possibly increased severity of disease and risk of death. (3-6)
A study was conducted in Qatar to evaluate the effectiveness of the Pfizer vaccine for the British variant. The Pfizer vaccine was shown to have 95% protection against COVID-19 in a study published in December 2020. (7) However, in the Qatar study, the estimated effectiveness of the Pfizer vaccine against the British variant was 89.5% at 14 days or more after the second dose of the vaccine.
Effectiveness of the vaccine against the British variant was 29.5% in individuals who only had 1 dose of the vaccine, emphasizing the importance of completing the full two-shot series. (8)
Another study used national surveillance data from India. Out of 8,472 COVID-19 cases documented in the study, 94.5% of them were due to the British variant. The study found that vaccine effectiveness at least seven days after receiving the second dose of the vaccine was 95.3%. (9)
The COVID-19 vaccines protect you from getting sick with the novel coronavirus, and variants like B.1.1.7. They also reduce the risk of fully vaccinated people spreading the virus.
Whether you get the Pfizer, Moderna, or Johnson & Johnson vaccine, all of them have shown to be effective against mild-to-severe cases of the novel coronavirus. All three vaccines are equally effective in clinical trials at preventing hospitalizations and death from coronavirus.
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1. Centers for Disease Control and Prevention. (n.d.). SARS-CoV-2 Variant Classifications and Definitions. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/variant-surveillance/variant-info.html#Concern
2. Centers for Disease Control and Prevention. (n.d.). US COVID-19 Cases Caused by Variants. Centers for Disease Control and Prevention. https://www.cdc.gov/coronavirus/2019-ncov/transmission/variant-cases.html
3. Davies NG, Abbott S, Barnard RC, et al. Estimated transmissibility and impact of SARS-CoV-2 lineage B.1.1.7 in England. Science. 2021;372(6538):eabg3055. doi:10.1126/science.abg3055
4. Davies NG, Jarvis CI; CMMID COVID-19 Working Group, et al. Increased mortality in community-tested cases of SARS-CoV-2 lineage B.1.1.7. Nature. 2021;593(7858):270-274. doi:10.1038/s41586-021-03426-1
5. Grint DJ, Wing K, Williamson E, et al. Case fatality risk of the SARS-CoV-2 variant of concern B.1.1.7 in England, 16 November to 5 February. Euro Surveill. 2021;26(11):2100256. doi:10.2807/1560-7917.ES.2021.26.11.2100256
6. Challen R, Brooks-Pollock E, Read JM, Dyson L, Tsaneva-Atanasova K, Danon L. Risk of mortality in patients infected with SARS-CoV-2 variant of concern 202012/1: matched cohort study. BMJ. 2021;372:n579. Published 2021 Mar 9. doi:10.1136/bmj.n579
7. Polack FP, Thomas SJ, Kitchin N, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. N Engl J Med. 2020;383(27):2603-2615. doi:10.1056/NEJMoa2034577
8. Abu-Raddad LJ, Chemaitelly H, Butt AA; National Study Group for COVID-19 Vaccination.
Effectiveness of the BNT162b2 Covid-19 Vaccine against the B.1.1.7 and B.1.351 Variants [published online ahead of print, 2021 May 5]. N Engl J Med. 2021;10.1056/NEJMc2104974.
9. Haas EJ, Angulo FJ, McLaughlin JM, et al. Impact and effectiveness of mRNA BNT162b2 vaccine against SARS-CoV-2 infections and COVID-19 cases, hospitalizations, and deaths following a nationwide vaccination campaign in Israel: an observational study using national surveillance data. Lancet. 2021;397(10287):1819-1829. doi:10.1016/S0140-6736(21)00947-8