Is there cause for concern over new Covid variant identified in France?

A new Covid-19 variant known as NB.1.8.1 has been identified in France, prompting fears of a new wave of infections.

The NB.1.8.1 strain has been observed four times in France the Centre national de référence (CNR) in Lyon which is tasked with monitoring emerging variants, confirmed to BFMTV, with cases found “both in hospital and in the community.”

The variant, which was first detected in France in March, is a sublineage of JN.1 which has been the dominant Covid strain worldwide since late 2023.

“A number of other countries have also reported it,” said CNR virologist Bruno Lina. These include Germany, Ireland, the Netherlands, Spain and Sweden, according to the European Centre for Disease Prevention and Control (ECDC).

‘Low level of circulation’

Data shared via the international genome tracking database GISAID suggests the strain is gaining a strong foothold in countries such as Japan, Taiwan, Thailand, Vietnam and China.

Taiwan and Hong Kong in particular have both reported more cases in recent weeks, with TVBS News and HK01 noting a rise in emergency room visits and deaths, particularly among elderly or vulnerable groups.

Does it cause more serious illness?

There is no indication that NB.1.8.1 causes more severe symptoms than other recent variants. 

In India, where it has circulated since late 2023, health officials told Indian media that “almost all of these cases are mild, with no hospitalisation required.”

However, experts are monitoring its potential to spread more efficiently. 

“The Chinese seem to suggest that this variant might have a growth advantage (...) it enters cells faster and replicates. Its characteristics probably indicate that this virus variant will become dominant in the future,” said Prof Lina.

Nonetheless, the World Health Organisation (WHO) assessed the global public health risk posed by JN.1 (of which NB.1.8.1 is a sublineage) as low, saying in April 2024:

“The available evidence on JN.1 does not suggest additional public health risks relative to the other currently circulating Omicron descendent lineages.

“Currently approved Covid-19 vaccines should remain effective”

What is the situation in France?

Detection in France was made possible by genomic sequencing, a method that Santé publique France says allows scientists to “detect any new variant and track its spread across the country.”

According to WHO figures, around 19% of Covid tests in France came back positive in the past week although testing has fallen sharply and is no longer reimbursed by Assurance Maladie for most people.

“There is no immediate concern,” one French health official commented. “But we need to stay alert, especially for vulnerable populations.”

France’s spring Covid vaccination booster campaign launched in April, with a focus on preventing a spread of cases among elderly and vulnerable people.

Anyone who wishes to get a booster for Covid can also make an appointment if they wish. 

People should not have a booster vaccine if they have received a Covid jab in the previous six months – however this is reduced to three months for those over 80 as well as any immunocompromised person

In these cases there is no charge to receive the booster.