Tracking SARS-CoV-2 Variants - WHO | World Health Organization

Skip to main content

• Home/
• Activities/
• Tracking SARS-CoV-2 variants

All viruses, including SARS-CoV-2, the virus that causes COVID-19, change over time. Most changes have little to no impact on the virus’s properties. However, some changes may affect the virus’s properties, such as how easily it spreads, the associated disease severity, or the performance of vaccines, therapeutic medicines, diagnostic tools, or other public health and social measures.

In June 2020, the WHO Virus Evolution Working Group was established with a specific focus on SARS-CoV-2 variants, their phenotype and their impact on countermeasures. This later became the Technical Advisory Group on SARS-CoV-2 Virus Evolution. In late 2020, the emergence of variants that posed an increased risk to global public health prompted WHO to characterize some as variants of interest (VOIs) and variants of concern (VOCs) in order to prioritize global monitoring and research, and to inform and adjust the COVID-19 response. From May 2021 onwards, WHO began assigning simple, easy-to-say labels for key variants.

Considerable progress has been made in establishing and strengthening a global system to detect signals of potential VOIs or VOCs and rapidly assess the risk posed by SARS-CoV-2 variants to public health. More specifically, in 2024 WHO launched a WHO Coronavirus Network (CoViNet) to facilitate early and accurate detection of coronaviruses and variant tracking including coordinating risk evaluations. It remains critical that these systems are maintained, and data are shared, according to good principles and in a timely fashion, as SARS-CoV-2 continues to circulate at high levels around the world. While monitoring the circulation of SARS-CoV-2 globally, it also remains essential to monitor their spread in animal populations and chronically infected individuals, which are crucial aspects of the global strategy to reduce the occurrence of mutations that have negative public health implications. In March 2023, WHO updated its tracking system and working definitions for variants of concern, variants of interest and variants under monitoring. They can be found here. The previous working definitions can be found here.

This content was last updated on 5 December 2025.

News

27 March 2024 News release

WHO launches CoViNet: a global network for coronaviruses

16 March 2023 Statement

Statement on the update of WHO’s working definitions and tracking system for SARS-CoV-2 variants of concern and variants of interest

4 January 2023 Statement

TAG-VE statement on the meeting of 3 January on the COVID-19 situation in China

Statement 28 November 2021 - Update on Omicron COVID-19 Situation reports 22 February 2022 Statement

Statement on Omicron sublineage BA.2

31 May 2021 Departmental update

WHO announces simple, easy-to-say labels for SARS-CoV-2 Variants of Interest and Concern

Disease Outbreak News

COVID-19 - United Kingdom of Great Britain and Northern Ireland 21 December 2020 | COVID-19 - United Kingdom of Great Britain and Northern Ireland

Disease Outbreak News

COVID-19 - Global 31 December 2020 | COVID-19 - Global

Disease Outbreak News

COVID-19 - Denmark 3 December 2020 | COVID-19 - Denmark

Currently circulating variants of concern (VOCs) as of 15 March 2023

Note: To better reflect the current variant landscape, which is dominated by Omicron descendent lineages, WHO updated its tracking system and working definitions of VOCs and VOIs on 15 March 2023.

4 October 2023

Updated working definitions and primary actions for SARS-CoV-2 variants Updated working definitions and primary actions for SARS-CoV-2 variants

Currently circulating variants of interest (VOIs) (as of 2 December 2024)

Pango lineage	Next strain clade	Genetic features	Earliest documented samples	Date of designation and risk assessments
JN.1#	24A	BA.2.86 + S:L455S	25-08-2023	18-12-2023 JN.1 Initial Risk Evaluation 18 December 2023 JN.1 Updated Risk Evaluation 9 February 2024 JN.1 Updated Risk Evaluation 15 April 2024

#Excludes JN.1 sublineages listed as VUMs below.

Currently circulating variants under monitoring (VUMs) (as of 5 Dec. 2025)

Pango lineage	Next strain clade	Genetic features	Earliest documented samples	Date of designation and risk assessments
KP.3.1.1	24E	KP.3 + S:S31-	27-03-2024	19-07-2024
LP.8.1	25A	JN1 + S:S31-, S:F186L, S:R190S, S:R346T, S:V445R, S:F456L, S:Q493E, S:K1086R, S:V1104L	01-07-2024	24-01-2025 LP.8.1 Initial Risk Evaluation 03 February 2025
NB.1.8.1	25B	JN1 + S:T22N, S:F59S, S:G184S,S:A435S, S:F456L, S:T478I, S:Q493E	22-01-2025	23-05-2025 NB.1.8.1 Initial Risk Evaluation 23 May 2025
XFG	25C	JN1 + S:T22N, S:S31P, S:K182R, S:R190S, S:R346T, S:K444R, S:V445R, S:F456L, S:N487D, S:Q493E, S:T572I	27-01-2025	25-06-2025 XFG Initial Risk Evaluation 25 June 2025
BA.3.2	Relative to Index:P9L, R21T, P26L, A67V, H69-, V70-, T95I, I101T, C136-, N137-, D138-, P139-, F140-, L141-, G142-, V143-, Y144-, Y145-, H146-, K147-, F157S, N164K, S172F, K187T, N211-, L212I, A243-, L244-, P251S, I326V, G339Y, A348P, S371F, S373P, S375F, R403K, D405N, R408S, K417N, A435S, N440R, V445A, G446D, L452W, N460K, S477N, T478N, E484K, G496S, Q498R, N501Y , K529N, E554D, E583D, D614G, H625R, N641K, V642G, E654K, H655Y , N679R, P681R, A688D, S704L, N764K, K795T, D796Y , A852K, S939F, Q954H, N969K, P1162R, D1184E	22-11-2024	05-12-2025 BA.3.2 Initial Risk Evaluation 05 December 2025

Technical Advisory Groups

Technical Advisory Group on SARS-CoV-2 Virus Evolution Technical Advisory Group on COVID-19 Vaccine Composition

Networks

The WHO Coronavirus Network (CoViNet)

Publications

All →

8 November 2022

WHO guiding principles for pathogen genome data sharing

WHO encourages the sharing of pathogen genome data to protect global public health. Sharing of pathogen genome data is critical for preventing, detecting,...

Download Read More

9 August 2021

Guidance for surveillance of SARS-CoV-2 variants: Interim guidance, 9 August 2021

This document aims to describe a minimum set of surveillance activities recommended at the national level to detect and monitor the relative prevalence...

Download Read More

8 January 2021

SARS-CoV-2 genomic sequencing for public health goals: Interim guidance, 8 January 2021

The growing understanding of how sequence information can contribute to improved public health is driving global investments in sequencing facilities and...

Download Read More

8 January 2021

Genomic sequencing of SARS-CoV-2: a guide to implementation for maximum impact on public health

Sequencing enabled the world to rapidly identify SARS-CoV-2 and develop diagnostic tests and other tools for outbreak management. Continued genome sequencing...

Download Read More

10 June 2021

2nd Global consultation on assessing the impact of SARS-CoV-2 Variants of Concern on Public Health Interventions

Download Read More

29 March 2021

Global Consultation on a Decision Framework for Assessing the Impact of SARS-CoV-2 Variants of Concern...

Download Read More

Q&A

All →

Coronavirus disease (COVID-19): Variants of SARS-COV-2 Coronavirus disease (COVID-19): Variants of SARS-COV-2

Coronavirus disease (COVID-19): Virus Evolution Coronavirus disease (COVID-19): Virus Evolution

Science in 5

All → Episode #20 - COVID-19 - Variants & Vaccines Episode #39 - Update on virus variants The WHO Coronavirus Network (CoViNet)