Table 2.
The details of SARS-CoV-2 variants, their mutations and characteristics.
| PANGO Linage | WHO label | Location | Identified | Key Spike mutations | Characteristics |
|---|---|---|---|---|---|
| Currently designated variants of concern (VOCs) | |||||
| B.1.1.7 | Alpha | United Kingdom | September 2020 | N501Y, D614G, P681H | This variant resulted in a highe hospitalization rate, need for ICU, and evasion from the immune system; however, was sensitive to vaccines. |
| B.1.351 |
Beta | South Africa | October 2020 | K417N, E484K, N501Y, D614G, A701V | Elevated hospitalization and need for ICU were associated with the Beta variant that accompanied with resistance to mAbs, convalescent plasma, and vaccine sera as well. |
| P.1 | Gamma |
Brazil | January 2021 | K417T, E484K, N501Y, D614G, H655Y | Gamma variant resulted in an elevated hospitalization and mortality rate that was resistant to mAbs, convalescent plasma, and vaccine sera. |
| B.1.617.2 | Delta | India | February 2021 | L452R, T478K, D614G, P681R | Delta variant has been a serious variant with much higher transmissibility, hospitalization rate and mortality. This variant was less susceptible to mAbs than the Wuhan strain. |
| B.1.1.529 | Omicron | South Africa and Botswana | November 2021 | A67V, D614G, T95I, H655Y, N679K, … | Omicron variant has the highest transmissibility, while has shown lower hospitalization rate and deaths. It has higher resistance to mAbs, but is weaker against cellular immunity. |
| Currently designated variants of interest (VOIs) | |||||
| C.37 | Lambda | Peru | December 2020 | L452Q, F490S, D614G | This variant showed an elevated immune resistance. |
| B.1.621 | Mu | Colombia | January 2021 | R346K, E484K, N501Y, D614G, P681H | It could evade immune defenses in a similar way to the Beta variant and had lower sensitivity to Abs. |
| Currently designated variants under monitoring (VUM) | |||||
| C.36 + L452R | N/A | Egypt | December 2020 | L452R, D614G, Q677H | This variant could escape from the cellular immunity restricted to HLA-A24. |
| AZ.5 (B.1.1.318) | N/A | India | January 2021 | E484K, D614G, P681H | Due to several mutations, it could escape from immune responses. |
| P.1 + P681H | N/A | Italy | February 2021 | D614G, E484K, H655Y, K417T, N501Y, P681H | N/A |
| B.1.617.2 + E484X (d) | N/A | India | April 2021 | L452R, T478K, D614G, P681R, E484X (d) | This variant is a part of B.1.617.2 (Delta). |
| B.1.617.2 + Q613H | N/A | India | April 2021 | L452R, T478K, D614G, P681R, Q613H | N/A |
| B.1.617.2 + Q677H | N/A | India | April 2021 | L452R, T478K, D614G, P681R, Q677H | It had resistance to mAbs. |
| B.1.617.2 + K417N | Delta plus | UK | June 2021 | L452R, T478K, D614G, P681R, K417N | This variant has been associated with high mortality rates, evasion from immunity and lower mAbs effects. |
| C.1.2 | N/A | South Africa | June 2021 | D614G, E484K, H655Y, N501Y, N679K, Y449H | It could evade mAbs effectively. |
| AY.4.2 | N/A | UK | June 2021 | L452R, T478K, D614G, P681R, A222V, Y145H | N/A |
| Formerly monitored variants | |||||
| B.1.1.523 | N/A | Russia | May 2020 | E484K, S494P | Some mutations in it were similar to the Delta variant which facilitate its escape ability from the immune responses. |
| B.1.427/B.1.429 | Epsilon | USA | September 2020 | L452R, D614G | The higher mortality rates and lower neutralization titers were two characteristics of the Epsilon variant. |
| C.16 | N/A | N/A | October 2020 | L452R, D614G | N/A |
| B.1.526.1 | N/A | USA | October 2020 | L452R, D614G | N/A |
| B.1.1.519 | N/A | Mexico | November 2020 | T478K, D614G | This variant was associated with increased hospitalization and mortality rates and reproduction number. |
| B.1.1.7 + E484K | N/A | UK | December 2020 | E484K, N501Y, D614G, P681H | N/A |
| B.1.525 | Eta | Nigeria | December 2020 | E484K, D614G, Q677H | It had a lower neutralization rate. |
| B.1.617.1 | Kappa | India | December 2020 | L452R, E484Q, D614G, P681R | Kappa variant showed a higher transmissibility* and greater ability to escape from vaccination. |
| B.1.214.2 | N/A | Belgian |
December 2020 | Q414K, N450K, ins214TDR, D614G | The severity and the ability to evade the immune responses were higher in this variant. |
| A.23.1 + E484K | N/A | UK | December 2020 | V367F, E484K, Q613H | It showed 1.3 % mortality rate. |
| A.28 | N/A |
N/A | December 2020 | E484K, N501T, H655Y | N/A |
| B.1.351 + P384L | N/A |
South Africa | December 2020 | P384L, K417N, E484K, N501Y, D614G, A701V | N/A |
| B.1.526 | Iota | USA | December 2020 | E484K, D614G, A701V | This variant had higher mortality among older adults and an enhanced ability to evade the immunity. |
| B.1.526.2 | N/A | USA | December 2020 | S477N, D614G | N/A |
| P.2 | Zeta | Brazil | January 2021 | E484K, D614G | It resulted in notable reduction in the neutralization ability of vaccine and mAbs. |
| P.3 | Theta | The Philippines | January 2021 | E484K, N501Y, D614G, P681H | N/A |
| A.27 | N/A | France | January 2021 | L452R, N501Y, A653V, H655Y | This variant could evade the immune responses. |
| B.1.351 + E516Q | N/A |
N/A |
January 2021 | K417N, E484K, N501Y, E516Q, D614G, A701V | N/A |
| B.1.1.7 + L452R | N/A | UK | January 2021 | L452R, N501Y, D614G, P681H | It induced higher resistance to mAbs and evaded HLA-restricted immunity. |
| B.1.1.7 + S494P | N/A | UK | January 2021 | S494P, N501Y, D614G, P681H | This variant induced resistance to Abs, particularly in combination with N501Y. |
| AT.1 | N/A | Russia | January 2021 | E484K, D614G, N679K, ins679GIAL | N/A |
| R.1 | N/A | Japan | January 2021 | W152L, E484K, G769V | This variant continued to appear in Japan and was associated with immune escape. |
| B.1.616(c) | N/A | France | February 2021 | V483A, D614G, H655Y, G669S | N/A |
| B.1.620 | N/A | Lithuania | February 2021 | S477N, E484K, D614G, P681H | It had higher severity with an enhanced ability to evade the immunity and mAbs neutralization. |
| B.1.617.3 | N/A | India | February 2021 | L452R, E484Q, D614G, P681R | N/A |
| AV.1 | N/A | UK | March 2021 | N439K, E484K, D614G, P681H | N/A |
WHO: World lealth organization; PANGO: Phylogenetic assignment of named global outbreak; PHE: Public health engineering; VOC: Variant of concern; ICU: Intensive care units; mAbs: Monoclonal antibody; VOI: Variant of interest; HLA: Human leukocyte antigen; N/A: Not available.
*; Cause community transmission in several countries, but have not yet been confirmed to be more infectious or transmissible.