There are various genetic variants of SARS-CoV-2, being emerging and spreading all-over the world in the COVID-19 pandemic. CDC has classified all variants into 3 categories:
| S. no. | Classification of variants | Definition (By CDC) |
| 1. | Variants of Concern (VOC) | Variant which are having evidence of an increased transmissibility,responsible for severe disease and increased hospitalizations or deaths),significant reduction ofneutralization antibodies generated after past infection or vaccination,reduced effectiveness of treatments or vaccines, or diagnostic detection failures. |
| The B.1.427 & B.1.429 (Epsilon), B.1.351 (Beta), B.1.1.7 (Alpha), P.1 (Gamma), and B.1.617.2 (Delta) variants. | ||
| 2. | Variants of Interest (VOI) | Possible attributes of a variant of interest: Evidence of genetic markers which affect the transmissibility, diagnostics, treatments, or immune escape Evidence which suggests an increased number of cases or separate outbreak clusters |
| B.1.525 (Eta), B.1.617.1(kappa), P.2(zeta), B.1.526(Iota), B.1.526.1 and B.1.617, B.1.617.3 variants. | ||
| 3. | Variants of High Consequence (VOHC) | A variant of high consequence must have following attributes: Failure of diagnostic kits Evidence of ineffectiveness of vaccines and increase in number of vaccine breakthrough cases, or very low production of antibodies after vaccination Evidence of ineffectiveness of treatments approved for emergency authorization. Increase in number of severe cases to hospitals. |
| Presently, there is no any SARS CoV-2 variant found to be in this category. |
The main description of each variant described by WHO is given below:
| WHO label | Pango lineage | Earliest documented samples | Date of designation |
| Alpha | B.1.1.7 | United Kingdom, Sep-2020 | 18-Dec-2020 |
| Beta | B.1.351 | South Africa, May-2020 | 18-Dec-2020 |
| Gamma | P.1 | Brazil, Nov-2020 | 11-Jan-2021 |
| Delta | B.1.617.2 | India, Oct-2020 | VOI: 4-Apr-2021 VOC: 11-May-2021 |
| Epsilon | B.1.427/B.1.429 | United States of America, Mar-2020 | 5-Mar-2021 |
| Zeta | P.2 | Brazil, Apr-2020 | 17-Mar-2021 |
| Eta | B.1.525 | Multiple countries, Dec-2020 | 17-Mar-2021 |
| Theta | P.3 | Philippines, Jan-2021 | 24-Mar-2021 |
| Iota | B.1.526 | United States of America, Nov-2020 | 24-Mar-2021 |
| Kappa | B.1.617.1 | India, Oct-2020 | 4-Apr-2021 |
| Lambda | C.37 | Peru, Aug-2020 | 14-Jun-2021 |
Concern about Delta Plus variant (B.1.617.2.1):
The World Health Organization (WHO) has classified B.1.617 variant which was first detected in India into three lineages: B.1.617.1, B.1.617.2, and B.1.617.3. Among these, B.1.617.2 (Delta) variant is designated on 11th May 2021 as Variant of Concern because of the increased transmissibility and increasing number of severe cases. Delta variant is now reported in 62 countries worldwide (as of June 1). The rest of two variants i.e., one- B.1.167.1- kappa and another B.1.617.3- Delta Plus variants, are considered in Variant of Interest because of now probably, its global prevalence is declining, by WHO.
What is Delta Plus variant?
There is an increasing concern about Delta Plus variant these days, when CDC has announced, there is a k417N mutation of spike protein of previously existing Delta variant (B.1.617.2).
Delta plus variant is now considered as an Emerging variant and notified as Variant of concern by CDC. It also allows to escape antibodies which is recently formed.
Symptom of Delta variant
Symptoms are somewhat different than the other variants. The common symptoms are:
- Headaches
- Sore throat
- Runny nose
- Bad cold – By children
Less common symptoms:
- Dry cough
- Loss of taste
- Loss of smell
How to Protect ourselves from Delta plus variant:
- Get vaccinated – Various vaccines are showing efficacy against new variants. Covishield showed 60% of efficacy while Pfizer showed 88% efficacious for the new strain (Delta plus). Other vaccines like Covaxin are still undergoing studies for the efficacy.
- Strictly follow home isolation tips and protocols, especially those having comorbidities
- Get yourself tested by RTPCR, if any symptoms arise.