COVID-19 Variant

COVID-19 Variants: Everything You Need to Know

Find out more about the COVID-19 variants spreading across the world and what it means in terms of vaccination, symptoms and testing.

by Calvyn Ee

As the COVID-19 pandemic continues, you may have read news articles that tell of new variants of the deadly virus and their potential effects. You might be wondering if these variants could still be curtailed by vaccinations, or if there might be yet another Movement Control Order (MCO) enacted to prevent its spread. With this article, we wish to address the concerns you may have on COVID-19 variants, from how these variants start, to vaccinations in the face of variants.

What are COVID-19 Variants?

COVID-19, an abbreviation for coronavirus disease 2019, is a highly contagious virus. Like other viruses, COVID-19 is also capable of changing over time. These changes can happen due to several factors, including environmental ones. While some changes are minor and do not impact its overall properties, other changes can be significant to the virus, such as becoming more contagious.

Changes to the virus are known as mutations. When a virus develops one or more of these mutations, it is identified as a variant.

It should be noted that such changes are expected among the scientific community, and are constantly monitored to help facilitate important medical decisions to be made. This has helped the medical field create vaccines, such as the Pfizer, Sinovac and AstraZeneca vaccines, to combat its spread.

Currently, the known variants present in Malaysia are Alpha, Beta, Delta, and more recently, Omicron. On a positive note, the Director-General of Health has confirmed that the second COVID-19 test of a South African student, the first recorded case of Omicron in the country, had returned negative. However, the Ministry of Health has advised caution on the possibility of other cases.

What Causes Variants?

The coronavirus spreads by infecting cells in your body, then makes copies of themselves. In the process of copying itself, there may be times when the genetic material carried by the virus is incorrectly copied; this results in a mutation. This happens purely by chance and at random. Not all variants will survive, but some will and continue to spread throughout the body, and later to other people.

COVID-19 variants should not be labelled as ‘viral strains’, as they are merely a different version of the virus after undergoing a genetic change that differs from the original COVID-19 sequence. A strain is more like a virus that has very different properties.

Each time a new variant emerges, the World Health Organization (WHO) will designate it with a letter from the Greek alphabet. This will be easier and more practical for discussing them in the public sphere.

Current COVID-19 Variants

COVID-19 Variant

The following section lists the major variants currently circulating the world.

Omicron

  • WHO label : Omicron
  • Pango lineage code : B.1.1.529
  • First documented : 24th November, 2021 (first sample collected 9th November)
  • Country/Region : South Africa (November 2021)
  • VOC designation : 26th November, 2021
  • No. of mutations : 32 mutations on the spike protein (preliminary data)
  • Infectivity : High (preliminary data)
  • Symptoms : Mild headaches for several days (preliminary indications of similar symptoms as other variants)
  • Risk of reinfection : High (preliminary data)
  • Notes : In October 2022, the World Health Organization (WHO) reported a new subvariant of the Omicron variant, XBB, that has been identified in 26 countries, including Malaysia. XBB is a combination of two other BA.2 Omicron subvariant, which are BA.2.10.1 and BA.2.75. 

    In December 2022, the two new Covid-19 variants – a sublineage of Omicron – named BA.5.2 AND BF.7 were believed to be driving the surge in infections in China. As of December 31st, 2022, there were 4,148 cases infected with BA.5.2 and three cases infected with BF.7 in Malaysia. Both of the new variants have a higher transmission rate compared to the other variants.

Delta

  • WHO label : Delta
  • Pango lineage code : B.1.617.2
  • First documented : December 2020
  • Country/Region : India (October 2020)
  • VOC designation : 11th May, 2021
  • No. of mutations : High
  • Infectivity : Twice as contagious than other earlier variants
  • Symptoms : Mild headaches, fever, persistent cough, sore throat (Shares symptoms as the original virus)
  • Risk of reinfection : High (especially among unvaccinated)
  • Notes : Delta accounts for at least 90 percent of new cases, and is a significant risk to unvaccinated groups. There is also some confusion between the Delta variant and another variant that is labelled ‘Delta Plus’. This is misleading, as ‘Delta Plus’ is an offshoot of the Delta variant, which is called AY.4.2. AY.4.2 is not a standalone variant, but instead part of the Delta family of variants. To put it simply, it is the Delta variant with a few specific mutations.

Alpha

  • WHO label: Alpha
  • Pango lineage code: B.1.1.7
  • First documented: September 2020
  • Country/Region: United Kingdom
  • VOC designation: 18th December 2020
  • No. of mutations: Approximately 23, maybe more
  • Infectivity : 1.5 times more transmissible than earlier variants
  • Symptoms : Fever, shortness of breath, cough, fatigue, change of sense of taste/smell (shares symptoms as the original virus)
  • Risk of reinfection : High (especially among unvaccinated)
  • Notes : Found in 192 locations worldwide, persons infected with the Alpha variant are 1.6 times at greater risk of death. Some mutations may also be found in the beta and gamma variants.

Beta

  • WHO label : Beta
  • Pango lineage code : B.1.351
  • First documented : May 2020
  • Country/Region : South Africa
  • VOC designation : 18th December, 2020
  • No. of mutations : High
  • Infectivity : 50 percent more transmissible than earlier variants
  • Symptoms : Mild headaches, fever, persistent cough, sore throat (Shares symptoms as the original virus)
  • Risk of reinfection : High (especially among unvaccinated)
  • Notes : Shares three mutations first seen in the Alpha variant, and is known to be more resistant to antibodies created through vaccination or recovery from a previous infection. Despite its infectivity, there is little evidence that Beta causes significant harm to an infected person’s health. Beta has also been overtaken by the more aggressive Delta variant, though Beta remains listed as a VOC by the WHO.

Gamma

  • WHO label : Gamma
  • Pango lineage code : P.1
  • First documented : November 2020
  • Country/Region : Brazil
  • VOC designation : 11th January, 2021
  • No. of mutations : High
  • Infectivity : Estimated 1.7 to 2.4 times more transmissible than other variants
  • Symptoms : Mild headaches, fever, persistent cough, sore throat (Shares symptoms as the original virus)
  • Risk of reinfection : High (especially among unvaccinated)
  • Notes : Most vaccines now offer significant protection from the Gamma variant.

Classification of Variants

With the emergence of new variants, WHO and various other healthcare organizations across the world have come up with a classification system to categorize variants based on their assessed risk to public health worldwide. There are currently three key categories of variants:

  • Variants of Concern (VOC)
  • Variants of Interest (VOI)
  • Variants Under Monitoring (VUM)

Variant classifications are not fixed because of the constantly evolving nature of COVID-19. Whenever a variant does not meet specific criteria outlined by the classification, it will be redesignated; variants that pose a much lower risk in contrast to other variants may also be reclassified. Reclassifying variants is done with the cooperation of various subject matter experts (such as virologists) and the use of accurate empirical data gathered from monitoring and studying variant activity worldwide.

Updates on variant reclassifications and other key data and trends are regularly published by WHO in the form of weekly updates, which can be accessed on their website.

Note that classification systems can vary slightly in different geographical regions. This may be due to the prevalence of other variants within the region that are not as prevalent as other variants, or due to a reduction or increase of risk of infection for certain variants. For example, both WHO and Malaysia’s Ministry of Health designate the Alpha variant as a VOC, while the Centers for Disease Control & Prevention in the United States designates Alpha as a VUM.

Variants of Concern (VOC)

VOCs are variants that are actively monitored. These variants are associated with one or more significant changes of global public health significance:

  • Increased risk of infectivity and spread, or other related factors; OR
  • Increased risk of virulence, or changes in symptoms present and its related effects; OR
  • Decreased effectiveness of public health and social measures or available diagnostics, vaccines, and/or therapeutics.

For VOCs, WHO requires significant investigation and research into listed variants, including the submission of complete genome sequences to public databases to help facilitate other studies, and performing detailed field investigations and lab assessments to improve understanding of the VOC and how it can potentially impact global public health measures.

All the variants listed in the previous section are still considered as VOCs by WHO, although regional health organizations may label them differently depending on the situation.

Variants of Interest (VOI)

VOIs have scientific evidence available on their properties that might significantly impact its spread, severity and/or immunity that could potentially affect global public health. However, the evidence is still preliminary or uncertain due to a lack of available data to facilitate understanding of its influence on global public health, or because it is not as widespread as VOCs. As such, VOIs could potentially be reclassified as a VOC if sufficient evidence points that to be the case; alternatively, VOIs could also be redesignated if the opposite were true.

Consistent, continuous investigations and observations, together with data sharing on VOIs by various parties, will thus be needed to ensure that VOIs do not pose public health risks.

Variants Under Monitoring (VUM)

These are variants with some indication that they could have similar properties to VOCs, but the evidence is weak or has not yet been thoroughly assessed. VUMs need enhanced monitoring and repeat assessments, pending new evidence, to determine their potential risk to global public health.

WHO recognizes that as the understanding of these variants improves, VUMs may be readily added or removed from the list. VOCs redesignated as VUMs may have an extension to monitoring its severity to ensure that it no longer proves to be a major health risk.

De-escalated/Formerly Monitored Variants

In some cases, some variants are redesignated to be of significantly lower risk, based on the following criteria:

  • The variant is no longer circulating;
  • The variant has been circulating for a long time but does not adversely impact global public health risk, AND
  • Scientific evidence proves the variant no longer has any concerning risk properties

This may arise from COVID-19 vaccinations being effective at preventing these variants from infecting vaccinated persons, or if variant mutations do not actively pose any health risk to infected persons (e.g. very mild or no symptoms detected).

Vaccinations and Variants

The challenge presented by COVID-19 variants comes from the way mutations can change how a variant infects others, how easily it can spread, and the potential dangers it can have to both vaccinated and unvaccinated persons.

Some studies have found that some variants are able to evade the protections offered by vaccines, or are more resistant to them. This could explain why reinfection can occur in those who have recovered from COVID-19, or even among the vaccinated.

Even though new variants have emerged, a number of studies conducted have found that vaccinations are still able to protect people from the worse effects of COVID-19. Vaccines are created to address a broad immune response that involves antibodies and cells in the body, so they are not immediately rendered ineffective every time a new variant emerges. It is still possible to change the composition of current vaccines to counter newer variants. Vaccine providers are also in the middle of testing updated vaccines for this purpose.

Prevention is still the best option to protect yourself, especially since deaths due to COVID-19 are caused by a multitude of health complications, such as organ failure or blood clots. By getting vaccinated, you reduce the overall risk of developing chronic complications that could affect your overall health in the long run, while also ensuring you keep your family and friends safe from infection.

While vaccinations do not prevent you from getting COVID-19, studies have shown that vaccinated individuals carry the virus for shorter periods of time than the unvaccinated, further safeguarding those around you. This goes hand in hand with current preventative measures in place to help protect everyone from COVID-19.

This is also why vaccine booster shots are important. Vaccinations do protect individuals from the significant effects of COVID-19, but over time, this layer of protection will gradually weaken and become less effective at keeping you safe. While some data suggest that vaccine efficacy can last at least six months, waning antibody counts will still occur. Vaccine booster shots are not a new thing, as these have occasionally been needed for children or adults to protect them from diseases such as hepatitis A and B, measles-mumps-rubella, and tetanus.

You can find out more about Malaysia’s vaccine booster program via this interactive infographic. You can also register via MySejahtera, but currently, it is only open to senior citizens, disabled persons, students who are studying abroad, persons who need to travel abroad for work or medical treatment, or for those traveling for their umrah.

Staying Safe

As such, WHO (and other healthcare organizations) recommends that the public continue to follow standard operating procedures as stipulated by the government in order to help break the chain of COVID-19 infections, and thus help fight the pandemic.

  • Maintain a distance of at least 1 metre from others
  • Wear a mask at all times, especially in public spaces
  • Avoid crowded areas, confined spaces, and close conversations
  • Maintain personal hygiene at all times (washing hands with soap, sanitizing areas, etc.)
  • Get vaccinated as soon as possible (if you have not been vaccinated yet)
  • Schedule your booster shot within the stipulated time period after your previous shots

Together, we can all do our part to adapt to the new normal and protect each other from COVID-19, and hopefully in time, the pandemic will finally come to an end.


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About the Writer
Calvyn Ee
Calvyn is an aspiring author, poet and storyteller. He spends his time reading, gaming and building stories with his action figure photography.
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