LONDON (BLOOMBERG) - A Cypriot scientist defended his assertion that a new strain of Covid-19 exists that combines characteristics of the Delta and Omicron variants, dubbed Deltacron.
Other scientists have speculated that Professor Leonidos Kostrikis' findings are a result of laboratory contamination.
But he told Bloomberg in an e-mailed statement on Sunday (Jan 9) that the cases he has identified "indicate an evolutionary pressure to an ancestral strain to acquire these mutations and not a result of a single recombination event".
Deltacron infection is higher among patients hospitalised for Covid-19 than among non-hospitalised patients, so that rules out the contamination hypothesis, said Prof Kostrikis, a professor of biological sciences at the University of Cyprus and head of the Laboratory of Biotechnology and Molecular Virology.
What's more, the samples were processed in multiple sequencing procedures in more than one country.
And at least one sequence from Israel deposited in a global database exhibits genetic characteristics of Deltacron, he said.
"These findings refute the undocumented statements that Deltacron is a result of a technical error," Prof Kostrikis said.
Viral genes determine the forms of proteins that perform a number of specific tasks.
Omicron and Delta each have mutations in the spike protein that affect their ability to enter human cells, with Omicron becoming more infectious as a result.
Recombinant forms of viruses can arise when there are multiple variants of a pathogen circulating, said Prof Nick Loman, a microbial genomics professor at University of Birmingham, who studies the coronavirus.
While a recombinant form of Delta and Omicron would not be a complete surprise, the finding from Cyprus is more likely a "technical artefact" that arose in the process of sequencing the viral genome, he said.
Cypriot Health Minister Michael Hadjipantela said on Sunday that the new variant is not of concern, and more details will be given at a news conference this week, Philenews reported.