A coronavirus variant can hide from standard tests


A new coronavirus variant discovered recently in France can hide from standard tests. The French ministry of health and social affairs announced earlier this week that among a cluster of 79 COVID-19 cases in Brittany, eight patients were infected with the new variant, but several of them tested negative. However they showed typical COVID-19 symptoms. The variant from Brittany is in the same group of strains as a variant first spotted in Southern California. Finnish researchers announced last month that they had identified a strain named Fin-796H with a mutation that made it difficult to detect with some nasal-swab tests, too. The standard molecular lab tests — known as reverse transcription polymerase chain reaction (RT-PCR) tests — hunt for an infection in a swab from a patient’s nose, looking for the coronavirus’s genetic code. With a modified spike protein the virus can escape detection. This may induce difficulties for the human effort to limit its spreading.


The new variant could be circulating undetected, at this time in France, possibly soon in the world. It not showed to be more infectious or more deadly. A good news: one European diagnostics company, the Novacyt Group, announced Thursday that its PCR tests can successfully detect the new variant. All eight of the French patients infected with the new variant died of the virus. In France, Prime Minister Jean Castex announced new lockdowns for Paris and the surrounding Ile-de-France region on Thursday.