Lagatar24 Desk
Paris, Jan 4: French researchers have discovered a new Covid variation, most likely of Cameroonian origin, and have given it the working name ‘IHU.’
According to a yet-to-be peer-reviewed study backed by the French government, the novel B.1.640.2 variation from the lineage has infected 12 persons in the country.
There are 46 mutations and 37 deletions in it.
“For twelve SARS-CoV-positive patients living in the same geographical area of southeastern France, qPCR testing that screen for variant-associated mutations showed an atypical combination,” said Philippe Colson, from IHU Mediterranee Infection, Marseille, France.
“However, it is too early to speculate on virological, epidemiological or clinical features of this IHU variant based on these 12 cases,” Colson added.
The index case (first patient) was a vaccinated adult who had returned to France from a vacation to Cameroon in central Africa, according to the study.
He got moderate respiratory symptoms three days after returning. Colson noted that his nasopharyngeal sample, taken in mid-November 2021, “showed an uncommon combination that did not correspond to the pattern of the Delta variant involved in almost all SARS-CoV-2 illnesses at the time,” and later to Omicron.
The identical mix of mutations were found in respiratory samples obtained from seven other SARS-CoV-2-positive patients residing in the same geographic area when analysed by qPCR. There were two adults and five youngsters in the group (below 15 years of age).
As advised by French public health officials, respiratory samples from these eight patients were sent to the Mediterranee Infection university hospital institute for SARS-CoV-2 genome sequencing.
SARS-CoV-2 genotype was discovered after several tests. A total of 46 mutations and 37 deletions were discovered, resulting in 30 amino acid changes and 12 deletions. The spike protein contains 14 amino acid changes and 9 deletions, including N501Y and E484K.
“This genotype pattern led to create a new Pangolin lineage named B.1.640.2, which is a phylogenetic sister group to the old B.1.640 lineage renamed B.1.640.1. Both lineages differ by 25 nucleotide substitutions and 33 deletions,” the study said.
“The mutation set and phylogenetic position of the genomes obtained here indicate, based on our previous definition, a new variant we named ‘IHU’,” Colson said.
He added that the data is “another example of the unpredictability of the emergence of SARS-CoV-2 variants”.
“Overall, these observations show once again the unpredictability of the emergence of new SARS-CoV-2 variants and their introduction from abroad, and they exemplify the difficulty to control such introduction and subsequent spread,” Colson said.
“SARS-CoV-2 variants have become a major virological, epidemiological and clinical concern, particularly with regard to the risk of escape from vaccine-induced immunity. The emergence of the new variant warrants the increase of genomic surveillance of SARS-CoV-2,” he said.