Alpha, Beta, Gamma or Delta the Covid19 variant of concern
Over the last 2 years, we have heard about quite a few COVID-19 variants. From Alpha, Beta, Gamma to Delta to Lambda, let us know all about the COVID -19 variants.
In the second episode of ‘Hello Health’, our host – Vivek Bhatia (Brand Head – Marketing & Communications) is joined by Dr. Souness Souto; whose area of focus over the last 2 years has been COVID care. Here, he sheds light on the types of COVID-19 variants, how dangerous are these, and how effective are our vaccines against them.
1. We hear a lot about variants and mutants – could you tell us what they mean?
All viruses – including SARS-CoV-2, the virus that causes COVID -19 – keeps on evolving over time. When a virus replicates or makes its own copies, the structure sometimes change a little bit – which is normal for a virus. These changes are called ‘mutations’. A virus with one or more new mutations is referred to as a “variant” of the original virus.
When a virus is widely circulating in a population and causing several infections, the likelihood of the virus mutating increases. The more opportunities a virus get to spread; the more it replicates.
Most viral mutations have little to no impact on the virus’s ability to cause infections and disease. But, depending on where the changes are located in the virus’s genetic material, they may affect a virus’s properties, such as transmission (for example, it may spread more or less easily) or severity (for example, it may cause more or less severe disease).
2. What is a variant of interest and what is a variant of concern?
Variant of Interest
A variant with specific genetic markers that have been 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 is termed as a ‘Variant of Interest’.
Example: Eta, Iota, Kappa, Lambda Variants.
Possible attributes of a Variant of Interest:
- Specific genetic markers that are predicted to affect transmission, diagnostics, therapeutics, or an immune escape.
- Evidence that it is the cause of an increased proportion of cases or unique outbreak clusters.
- Limited prevalence or expansion in countries.
- A variant of interest might require one or more appropriate public health actions, including enhanced sequence surveillance, enhanced laboratory characterization, or epidemiological investigations to assess how easily the virus spreads to others, the severity of disease, the efficacy of therapeutics and whether currently authorized vaccines offer protection.
Variant of Concern
A variant for which there is evidence of an increase in transmissibility, more severe disease (e.g. increased hospitalizations or deaths), significant reduction in neutralization by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures is termed as a ‘Variant of Concern’.
Example: Alpha, Beta, Gamma, Delta Variants.
Possible attributes of a Variant of Concern:
In addition to the possible attributes of a variant of interest:
- Evidence of impact on diagnostics, treatments, or vaccines.
- Widespread interference with diagnostic test targets.
- Evidence of substantially decreased susceptibility to one or more class of therapies.
- Evidence of significant decreased neutralization by antibodies generated during previous infection or vaccination.
- Evidence of reduced vaccine-induced protection from severe disease.
- Evidence of increased transmissibility.
- Evidence of increased disease severity.
Variants of concern might require one or more appropriate public health actions – such as notification to WHO under the International Health Regulations, reporting to CDC, local or regional efforts to control spread, increased testing, or research to determine the effectiveness of vaccines and treatments against the variant. Based on the characteristics of the variant, additional considerations may include the development of new diagnostics or the modification of vaccines or treatments.
3. What are the different variants of SARS- CoV-2 known? Which are the dangerous ones?
At present, the expert group convened by WHO has recommended using letters of the Greek Alphabet, i.e., Alpha, Beta, Gamma, Delta to name the SARS CoV2 variants, which will be easier and more practical to discuss by non-scientific audiences.
Naming the variants as per the country of origin has been discontinued to avoid any possible stigma.
There are many variants of the SARS CoV2 virus, but the most notable ones are the alpha, beta, gamma and delta variants – the variants of concern as mentioned above, of which the alpha and delta variants are the most dangerous ones.
The alpha variant is associated with increased transmission and hospitalisation with significant mortality, while the delta variant is more severe with respect to the same traits and effects as compared to the alpha variant.
The delta variant which originated in India was the one responsible for the massive second wave of the pandemic in the country. It took a major toll on the healthcare systems which were overwhelmed to cope with the increasing numbers and severity associated with the disease. That by far, makes it the most dangerous variant.
4. Are the vaccines effective against the dangerous variants?
Being fully vaccinated gives a person roughly the same protection against Delta as the Alpha, Beta and Gamma Viruses. The data shows that the vaccines are doing even better than previous studies suggested against the variants in terms of symptomatic infection as well as hospitalization and death.
The side effects associated with the vaccines are minimal to none. Like any other vaccine, the COVID vaccines also do have side effects but when you assess the risk benefit ratio, the benefits of vaccination against SARS COV2 significantly outweighs the risks.
Vaccines are a critical tool in the battle against COVID-19, and there are clear public health and lifesaving benefits to using the tools we already have. We must not put off getting vaccinated because of our concerns about new variants, and must proceed with the vaccination; even if the vaccines may be somewhat less effective against some of the COVID -19 virus variants. We need to use the tools we have in hand currently; even while we continue to improve those tools. We are all safe only if everyone is safe.
So please go ahead and get your COVID-19 vaccine at the earliest. Help us to help you fight the pandemic at the earliest.