Health officials said on Tuesday that a new coronavirus variant sweeping through north-west France could evade detection in standard tests.
The variant, first spotted in Brittany, “doesn’t suggest either increased severity or increased transmissibility” but there are indications its presence in patients is harder to confirm.
Brittany's health workers are trying to establish the extent of the variant's circulation as French authorities fear a third wave of the pandemic has arrived.
“An evaluation is under way to assess the possible impact of these genetic modifications ... on a lack of recognition by virological tests leading to an underdiagnosis,” the general directorate of health said.
The World Health Organisation confirmed it was investigating the variant because of its apparent ability to evade detection in people who had PCR tests.
Eight people were identified in the town of Lannion as carriers of the variant in a cluster of 79 cases.
Pierre Tattevin, professor of infectious diseases at the University of Rennes, said that in addition to these eight cases, there were “several dozen over the past few weeks”.
The incidence of the coronavirus in Brittany has risen steadily for about six weeks and is now at 133 cases per 100,000 people.
“We are in a sort of third wave of the epidemic, characterised by numerous variants,” French Prime Minister Jean Castex told Parliament.
President Emmanuel Macron said new lockdown could be introduced within days. A government source said Mr Macron would receive an update on the epidemic’s evolution from advisers on Tuesday.
His government recently paused use of AstraZeneca’s Covid-19 vaccine.
The European Medicines Agency reiterated on Tuesday that there was “no indication” the shot raised the risk of blood clotting after more than a dozen EU states suspended use of the drug until investigations are concluded.
AstraZeneca said there was no cause for concern and that proportionally fewer thrombosis cases were reported in immunised people than among the general population.
