Amelie and Ludo Khayat at the COVID-19 intensive care unit of the La Timone hospital in Marseille, southern France, on December 23, 2021. Ludo, 41, is recovering after 24 days in a coma and on a ventilator. Amelie began visiting her husband after he tested negative for the virus. Twelve COVID patients in Marseille were found to have been infected with the new IHU strain. Image Credit: AP

A new coronavirus variant that causes COVID-19 is in the news: the French variant. Actually, it’s not new. It was discovered in November, but that was when Omicron hogged the headlines and continues to spread around the world.

The new variant, found in Marseille, France, has had a quiet existence. It hasn’t spread to other countries. Experts believe the IHU variant, or B.1.640.2, is unlikely to cause severe infections like Delta or spread as fast as Omicron.

Here’s what we know about the French variant.

What is the French variant?

The IHU variant, also known as B.1.640.2, has been named after the Mediterranee Infection University Hospital Institute (IHU) in Marseille, where researchers first identified the strain. The variant has 46 mutations, nine of which are on the spike protein that helps the virus enter the human cell. In contrast, 35 of Omicron’s 50 mutations are on the spike protein.

Who was the first case?

According to Professor Philippe Colson, head of the IHU department that discovered the variant, the first patient or the “index case” was a fully-vaccinated man who had returned from a trip to the central African nation of Cameroon in November. He tested positive three days after returning to France; he had developed mild respiratory symptoms a day earlier.

Reports said the IHU strain was first uploaded to variant-tracking database GISAID on November 4, more than two weeks before Omicron was sequenced.

How infectious is the new variant?

The variant has the N501Y mutation, which experts say can make it more transmissible. And the 46 mutations are also worrying, but there are no data to indicate it will be more infectious. Experts caution that just because it’s a new variant doesn’t mean IHU will be as contagious or severe as other strains of COVID-19.

US epidemiologist and health economist Eric Feigl-Ding tweeted: “What makes a variant more well-known and dangerous is its ability to multiply because of the number of mutations in relation to the original virus.

“This is when it becomes a ‘variant of concern’ — like Omicron, which is more contagious and more past immunity evasive. It remains to be seen in which category this new variant will fall.”

Should we be worried? What experts say

Medical experts have dismissed the threat posed by the IHU variant, saying it hasn’t been as infectious or virulent as Delta or Omicron. In Geneva, Abdi Mahamud, a WHO incident manager, said that it’s too early to speculate on virological, epidemiological or clinical features of the variant.

Tom Peacock, a virologist at Imperial College London, tweeted that the IHU variant is not worth worrying about too much. “This virus has had a decent chance to cause trouble but never really materialised as far as we can tell,” he said.

Feigl-Ding said the ICU rates are far higher in the southern region where the variant cluster was found, compared with the rest of France. But Francis Balloux, a geneticist at University College London, dismissed it, saying the strain is not linked with a spike in cases or hospitalisations.

How many cases have been identified?

The IHU variant has infected 12 people in southern France, although experts expect the actual toll to be around 30.

Where are the cases found?

All the cases were discovered in Marseille, southern France. Besides the 12 cases, several other COVID-positive patients, including children living in the same area, were also found to have been infected with variant, according to Colson, who has published online details of the IHU variant in a paper last month.

The variant has not been reported from other countries.

What’s the status of the variant?

The World Health Organisation (WHO) has not called it a variant of concern like Delta or Omicron. It is not yet labelled a variant under investigation, but WHO is studying the strain to give more clarity and guidance.

Two new genomes have just been submitted, according to Colson, who is yet to publish the details in a medical journal.

Will vaccines work against the IHU variant?

The strain carries the E484K mutation that could make it more resistant to vaccines. French scientists believe the 46 mutations in the new variant could make it more resistant to vaccines and more infectious.

Since only a small amount of cases is identified, It is too early to tell if vaccines work. And all the cases have come from one region — the Marseille geographical area, the southern Alps region in France.