The health ministry in France has reported a new SARS-CoV-2 variant, and they suspect it may be more difficult to identify using the current gold standard method of detecting COVID-19: a PCR test.
The new "Breton" variant – detected in Brittany in western France – had been isolated in a cluster of eight hospitalized patients in Lannion, all of whom had the classic symptoms of COVID-19. They had first tested negative using a PCR test, and then tested positive using blood tests or deep respiratory tissue sampling detection. The eight patients have since died.
The Institut Pasteur's national reference center suggests the new variant detected in France is derived from a current known variant, clade 20C. The researchers are now investigating whether it is genetic modifications in the new variant that might be making it harder to detect, or whether the detection of the new variant was missed due to errors in the PCR tests themselves, which could have provided false negatives.
A statement released by the health ministry said that early analysis does not indicate the new variant to be more transmissible or that it could be causing more severe disease, but investigations are currently underway to confirm this.
"In-depth investigations are underway in order to better understand this variant and its impact. Experiments will also take place to determine how this variant reacts to vaccination and to the antibodies developed during previous infections," the statement by the health ministry translates to.
Variants are a natural occurrence in any virus and its evolution as it continues to replicate and spread through a population.
Thus far, a couple of SARS-CoV-2 variants have raised concerns Internationally – those being the, UK, South African, and Brazilian variants, as there have been indications that they may have increased transmissibility or have higher mortality rates.
However, what seems different about the new variant in France so far is that it was missed by standard PCR testing. Although the early analysis does not suggest the variant is more transmissible or has increased mortality, it does raise concerns that this variant of the virus could escape detection by common PCR testing practices and therefore circulate undetected, hampering contact tracing efforts.
Hence a major effort is currently underway in France to understand the new variant. The health ministry in France has also reported the variant to International authorities, and the World Health Organization has put the variant under surveillance.
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