By Dr. Seleem R. Choudhury
As an increasing portion of the global population continues to receive the COVID vaccine, public health experts, government officials, and healthcare professionals continue to monitor variants emerging around the world. With recent spikes of infections in India that have brought devastating death tolls and an overwhelmed healthcare system, it is clear that reaching the “end” of COVID and moving forward into a sense of normalcy will not be a straightforward process.
What are mutations?
Mutations are tiny errors in our genome sequencing, and are often drivers within evolution (Carlin, 2011). As a child I was occasionally naughty, and as punishment I recall having to write lines. I would have to write and repeat whatever words were deemed necessary for me to learn my lesson and change my behavior. However, as I wrote the lines, slight changes in my handwriting occurred on a word here or a letter there. Though the message remained the same, these accidental small changes caused some lines to look different.
All viruses evolve and change over time. This allows a virus to not only survive, but thrive (Tajouri, 2020). Just like my handwriting, these changes, or mutations, happen accidentally and cause the virus’s genome sequence to look different. When a virus undergoes one or two mutations, this is called a “variant.” Occasionally, the virus will mutate in such a way that the virus can copy itself more efficiently or enter our cells more easily (Cleveland Clinic, 2021). With more than 141 million infections worldwide at the time of this publication—a number that continues to climb—the virus has ample opportunity to mutate.
Current COVID mutations
Currently, there are many different versions, or variants, of COVID circulating. As with any virus, most variants come and go; others persist but don’t spread widely among the population. However, several prominent variants present themselves and gain notoriety, and eventually cause concern.
It is important in any discussion of variants of this virus to make clear that while variants are referred to as “the U.K. strain” or “South African variant,” the actual origin of any given mutation is difficult to prove, and individual countries should not be blamed for variants bearing their name (Ellyatt, 2021).
(Roberts, M., 2021)
The World Health Organization (WHO) calls the variants in the graphic above “variants of concern,” signifying “strains that pose additional risks to public health” (Gale, 2021). Recently joining the list of variants of concern is the Indian variant called B1617 (Roberts, G., 2021). The WHO has also coined the term “emerging variants of interest” for mutations that “warrant close monitoring because of their potential risk” (Gale, 2021).
These variants of concern are worrisome for varying reasons and degrees, but are primarily related to ease of transmission, severity of the illness for those infected, the likelihood the variant will infect people who have already contracted COVID, potential impact on vaccination efficacy, and the prevalence of the mutation in the population (Gale, 2021; Centers for Disease Control and Prevention, 2021).
Tracking these variants is vitally important in order to improve the design of vaccines to be effective against new variants. However, changes to those vaccines take several months, and are a mid- to long- term solution. More pressing in the short term is the increase of sequencing efforts, which experts have criticized for being “small and uncoordinated,” in order to “adequately track where variants are spreading and how quickly” (Zimmer, 2021; Zimmer, & Weiland, 2021).
The vaccine and mutation
There is anxiety regarding the unpredictability of COVID variations and the efficacy of the vaccine against such mutations. While data on the Indian variants is scarce at the time of this article’s publication, a recent study of people worldwide who had received the Pfizer vaccine, including 44,000 people in South Africa who were predominantly exposed to the B.1.351 variant, found that the vaccine was 100 percent effective against severe disease and death (Business Wire, 2021). Additional Pfizer data showed that the vaccine is “97 percent effective against symptomatic COVID-19, hospitalizations, and death” (Business Wire, 2021). The vaccine also “held up against the B.1.1.7 variant” (Ries, 2021). The Moderna, AstraZeneca, and Johnson & Johnson data demonstrated similar levels of effectiveness (Business Wire, 2021; Laguipo, 2021; Deutsche Welle, 2021).
There are also ongoing trials with unpublished data that demonstrates a booster shot given to previously vaccinated individuals improved the antibody titer responses against several variants of concern (Hippensteele, 2021). Moreover, leading pharmaceutical companies have discussed adapting the vaccine to deal with variants. Recently the first “tweaked vaccine” announced by Moderna successfully neutralized several variants in lab trials (Boseley, 2021).
(Woodward, 2021)
In short, vaccines offer effective protections against the variants of concern, especially in terms of preventing serious symptoms and death (Ries, 2021). The World Health Organization states that the COVID “vaccines that are currently in development or have been approved are expected to provide at least some protection against new virus variants because these vaccines elicit a broad immune response involving a range of antibodies and cells. Therefore, changes or mutations in the virus should not make vaccines completely ineffective (World Health Organization, 2021).”
The future of the virus
One of the challenges for public health experts is understanding what the end of the virus will look like and, furthermore, how it will be measured: daily deaths, hospital admissions, vaccination rates, percentage of the population who have been vaccinated, etc. Regardless of the measurements used, variants have a major impact on the endpoint. Rather than widespread, rapid transmission of the virus, we may see more “sporadic and localized” outbreaks (Joseph, & Branswell, 2021).
Vaccine hesitancy around the globe, in addition to the emergence of new variants, makes herd immunity unlikely (Aschwanden, 2021). However, there is growing evidence that vaccines not only protect people from contracting COVID, but also reduce transmission of the virus (Joseph, & Branswell, 2021). Even so, the probability exists that the only way to mitigate outbreaks is with regular booster vaccines due to more transmissible future mutations of the virus (Faulconbridge, 2021). Though COVID will not be eliminated in the near future, there is a strong likelihood that it can be managed.
Resources
Aschwanden, C. (2021). Five reasons why COVID herd immunity is probably impossible. Nature.
Boseley, S. (2021). Tweaked Moderna vaccine ‘neutralises Covid variants in trials.’ The Guardian.
Business Wire (2021). Moderna COVID-19 Vaccine Retains Neutralizing Activity Against Emerging Variants First Identified in the U.K. and the Republic of South Africa. Business Wire.
Business Wire (2021). Pfizer and BioNTech Confirm High Efficacy and No Serious Safety Concerns Through Up to Six Months Following Second Dose in Updated Topline Analysis of Landmark COVID-19 Vaccine Study. Business Wire.
Business Wire (2021). Real-World Evidence Confirms High Effectiveness of Pfizer-BioNTech COVID-19 Vaccine and Profound Public Health Impact of Vaccination One Year After Pandemic Declared. Business Wire.
Carlin, J. L. (2011) Mutations Are the Raw Materials of Evolution. Nature Education Knowledge 3(10):10.
Centers for Disease Control and Prevention (2021). Global Variants Report. Centers for Disease Control and Prevention.
Centers for Disease Control and Prevention (2021). SARS-CoV-2 Variant Classifications and Definitions. Centers for Disease Control and Prevention.
Cleveland Clinic (2021). What Does It Mean That the Coronavirus Is Mutating? The Cleveland Clinic.
Deutsche Welle (2021). WHO experts advise J&J jab for coronavirus mutants. DW.
Ellyatt, H. (2021). Coronavirus mutations: Here are the major Covid strains we know about. CNBC.
Faulconbridge, G. (2021). Exclusive: Regular booster vaccines are the future in battle with COVID-19 virus, top genome expert says. Reuters.
Gale, J. (2021). Why the Mutated Coronavirus Variants Are So Worrisome. Bloomberg Quint.
Hippensteele, A. (2021). Moderna Releases Positive Initial COVID-19 Vaccine Booster Data Against Variants of Concern. Pharmacy Times.
Joseph, A., & Branswell, H. (2021). The short-term, middle-term, and long-term future of the coronavirus. Stat News.
Laguipo, A.B.B. (2021). Oxford-AstraZeneca vaccine effective against B.1.1.7 SARS-CoV-2 variant. News Medical.
Ries, J. (2021). COVID-19 Vaccines Are Still Effective Amid Rising Number of Variants. Healthline.
Roberts, G. (2021). Everything we know about the Indian COVID-19 variant so far. World Economic Forum.
Roberts, M. (2021). What are the Indian, Brazil, South Africa and UK variants? BBC News.
Tajouri, L. (2020). What is a virus? How do they spread? How do they make us sick? The Conversation.
Woodward, A. (2021). One chart shows how well COVID-19 vaccines work against the 3 most worrisome coronavirus variants. Business Insider.
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Zimmer, C., & Weiland, N. (2021). C.D.C. Announces $200 Million ‘Down Payment’ to Track Virus Variants. New York Times.
Zimmer, C. (2021). U.S. Is Blind to Contagious New Virus Variant, Scientists Warn. New York Times.U.S. Is Blind to Contagious New Virus Variant, Scientists Warn