The ability of COVID-19 tests to detect emerging genetic variants of SARS-CoV-2
The TGA is undertaking a post-market review of all Point of Care and Laboratory tests included in the ARTG, which are intended to identify patients with COVID-19, to ensure they can detect the emerging SARS-CoV-2 genetic variants and remain accurate.
The Therapeutic Goods Administration (TGA) is undertaking a post-market review of all point-of-care (PoC) and laboratory tests included in the Australian Register of Therapeutic Goods (ARTG) that are intended to identify individuals with COVID-19. The review verifies whether these tests can accurately detect emerging genetic variants of the SARS-CoV-2 virus; and complements the TGA's ongoing review of the overall performance of PoC tests.
Like all viruses, SARS-CoV-2 can mutate over time, resulting in genetic variation among the viral strains circulating in the community. There are various potential consequences arising from these genomic mutations. The aim of this post-market review is to ensure all viral diagnostic tests continue to be able to detect known and emerging genetic variants. If the kits are not able to do so, this could potentially lead to false negatives and delay the treatment or isolation of individuals with COVID-19.
The TGA is monitoring the emerging variants of SARS-CoV-2 with at least 5% prevalence in the global population (i.e. mutations that occur in at least 5% of each viral variant) and will keep monitoring these variants as they continue to mutate.
The impact of the variants on test performance can be influenced by the variant's prevalence in the population (372kb) and the design of the test kit.
This web page and the linked tables will be updated during the course of the post-market review with information about each test kit's performance against the variants.
Multiple variants of SARS-CoV-2 have been emerging and circulating globally since the start of the pandemic.
The nomenclature system and a list of the variants are maintained by the World Health Organisation (WHO) and the Communicable Diseases Genomics Network (CDGN).
The variants are broken down into classifications, including:
- variants of concern (VOC)
- variants of interest (VOI)
- variants under monitoring (VUM)
- and formerly monitored variants (FMV).
During the pandemic, the understanding of the impacts of SARS-CoV-2 variants on public health has improved, and based on the phenotypic characteristics (transmissibility, disease severity, risk of reinfection, and impacts on diagnostics and vaccine performance), variants may be reclassified.
|Classification||WHO / CGDN||Pango Lineage||GISAID clade/lineage||Nextstrain clade||First identified|
|VOC||Alpha||B.1.1.7||GRY (formerly GR/501Y.V1)||20I (V1)||United Kingdom, Sep 2020|
|VOC||Beta||B.1.351||GH/501YV2||20H (V2)||South Africa, May 2020|
|VOC||Gamma||P.1||GR/501Y.V3||20J (V3)||Brazil, Nov 2020|
|VOC||Delta||B.1.617.2 (+ AY lineages)||G/478K.V1||21A||India, Oct 2020|
|GR/484A||21K||Multiple countries, November 2021|
|VOI||Lambda||C.37||GR/452Q.V1||21G||Peru, December 2020|
|VOI||Mu||B.1.621||GH||21H||Colombia, January 2021|
|VUM||Kappa||B.1.617.1||G/452R.V3||21B||India, Oct 2020|
|VUM||Iota||B.1.526||GH/253G.V1||21F||United States, November 2020|
|VUM||Eta||B.1.525||G/484K.V3||21D||Multiple countries, December 2020|
|FMV||Epsilon||B.1.427, B.1.429||GH/452R.V1||21C||United States, California|
Information for laboratories and health professionals
The three main types of SARS-CoV-2 tests include:
- nucleic acid tests (NATs), which detect SARS-CoV-2 viral RNA
- rapid antigen tests (RATs), which detect antigen viral proteins from SARS-CoV-2
- serology tests, which detect IgM and/or IgG antibodies against SARS-CoV-2.
Laboratory and health professionals should be aware that:
- Genetic variants of SARS-CoV-2 may yield false negative test results
- NATs that utilise multiple genetic targets to determine a final result are less likely to be impacted by increased prevalence of genetic variants.
The TGA recommends that negative results be considered in combination with clinical observations, person’s history and epidemiological information; and that repeat testing using a different test (with different genetic targets) be considered if COVID-19 is still suspected after a negative test result.
Throughout the course of the review, if the TGA identifies any test kits with a decrease in sensitivity against a variant, the TGA will work with the sponsor to add additional warnings and precautions into the Instructions for Use (IFU).
Post market reviews
Post-market review of nucleic acid tests
The TGA is undertaking desktop analysis of all NAT kits on the ARTG to determine whether they will be impacted by the known variants, with ongoing activity to assess their ability to detect all emerging variants of interest.
Information about each test kit's performance against the emerging variants of concern will be published as it becomes available.
Post-market review of antigen and rapid antigen tests
The TGA is undertaking desktop analyses of all laboratory antigen and RATs included in the ARTG to determine whether they have been impacted by the current known variants, with ongoing activity to assess their ability to detect all emerging variants of interest.
In addition, the post-market review includes laboratory testing of all PoC and self-test RAT test kits included in the ARTG to validate their performance in detecting the Delta variant (and other emerging variants of concern).
Post-market review of serology tests
The current post-market review monitors the ability of COVID-19 diagnostic test kits to detect emerging genetic variants of the SARS-CoV-2 virus. Serological assays fall outside of the scope of the current review.
Serology tests detect the presence of antibodies in the blood from the body's adaptive immune response to an infection, like COVID-19. They generally provide historic information that indicates whether an individual has past exposure to SARS-CoV-2. They do not detect the virus itself. It is not yet evident that the detection of antibodies reflects the presence of protective immunity, so the detection of antibodies may not exclude remaining infectivity in a patient.
The TGA has undertaken a post-market review of all serology-based point-of-care tests included in the ARTG. The outcomes of this review have been published on the Post-market evaluation of serology-based point of care tests webpage.
Conditions imposed on all COVID-19 serology tests approved for ARTG inclusion
All COVID-19 tests that are included in the ARTG based on an expedited assessment process are subject to additional non-standard conditions, that inform post-market validations as experience and knowledge around COVID-19 diagnostic testing grows.
The conditions require that additional evidence to support the ongoing safety and performance of the device be provided to the TGA within 12 months of approval.
Note: Some states and territories have prohibited or restricted use of serology rapid screening tests. Please visit the relevant government website for further information.
Consumers and health professionals are encouraged to report problems with medical devices. Your report will contribute to the TGA's monitoring of these products. For more information see the TGA Incident Reporting and Investigation Scheme (IRIS).
The TGA cannot give advice about an individual's medical condition. You are strongly encouraged to talk with a health professional if you are concerned about a possible adverse event associated with a medical device.