This week, Gisaid, a global community of scientists that shares virus information, posted that the first solid evidence for this variant had been shared by the Pasteur Institute in France. Gisaid says the variant has been identified in several regions of France and appears to have been circulating since the start of the year. “Genomes with a similar profile have been also identified in Denmark and the Netherlands,” Gisaid says.
Six things to know:
1. Three COVID-19 infections in southern France were identified with a delta 21J/AY.4-omicron 21K/BA.1 recombinant, or deltamicron, according to a study which has yet to be peer-reviewed. It found that the hybrid genome has signature mutations of the two lineages. It’s similar to cases reported for 15 other patients sampled since January 2022 in Europe. The mutation cannot be identified or is misidentified with current PCR variant screening, so researchers designed and implemented a new test to diagnose the variant.
2. The new coronavirus variant has been detected in France, the Netherlands and Denmark, according to WHO officials. It’s also been found in the U.S.
3. The US study findings come from the Helix lab in San Mateo, California, which works with the CDC. The lab sequenced 29,719 coronavirus samples collected nationwide from 22 Nov 2021 to 13 Feb 2022, according to the findings cited by USA Today. Researchers found two infections involving different versions of deltacron, resulting from the combination of delta and omicron genetic material. Twenty other infections had both the delta and omicron variants, with one case having delta, omicron and deltacron. The recombinant variant appears unlikely to spread as easily as delta or omicron, says William Lee, PhD, Vice President of Science at Helix, told USA Today.
4. “We have not seen any change in the epidemiology with this recombinant,” according to WHO Technical Lead Maria Van Kerkhove during the media briefing on 9 March 2022. “We haven’t seen any change in severity. But there are many studies that are underway.”
5. Recent findings from the Pasteur Institute in France also provide evidence of a delta and omicron recombinant. In response to the findings, Dr. Van Kerkhove urged individuals to revisit a 22 Feb 2022 WHO briefing where officials discussed the possibility of coronavirus recombinants.
“This is to be expected, especially with intense circulation of omicron & delta,” says Dr. Van Kerkhove.
6. Researchers have identified other potential recombination mutations, such as multiple cases of alpha infections that also had amino acid substitutions that correspond to the delta-plus, iota and omicron variants, according to a study published 8 March 2022 in the Journal of Clinical Investigation. The researchers conducted a “deep sequencing analysis” of COVID-19 among vaccine-breakthrough patients and found “a rich reservoir of mutant types.”