A scientist in Cyprus is defending the existence of a new strain of COVID-19 he found that is a combination of Delta and Omicron.
Leondios Kostrikis, professor of biological sciences at the University of Cyprus, said last week he found 25 cases of what he's labelled the 'Deltacron' strain. The co-infection has this name because of its Omicron-like genetic signatures in the Delta genomes, he says.
His data showed the likelihood of Deltacron infection is higher among patients who have been hospitalised with the virus than those who aren't.
But other scientists don't believe Kostrikis has found a new strain. Dr Tom Peacock, a virologist at Imperial College London, says Deltacron is "quite clearly [laboratory] contamination" when sequencing took place and it is "likely not real".
"Most likely [all the samples] were all sequenced on the same sequencing run in the same lab on the same day which had a contamination issue - this is what's generally been found to have happened in the past," he tweeted.
Molecular biologist Eric Topol calls it a "scariant" and it is "one less thing to worry about".
Kostrikis disagrees, telling Bloomberg that the cases he's identified "indicate an evolutionary pressure to an ancestral strain to acquire these mutations and not a result of a single recombination event".
He says since the Deltacron infection is higher among patients hospitalised for COVID-19 than those who aren't hospitalised, that rules out the contamination hypothesis. He adds that the samples were processed in multiple sequencing procedures in more than one country, and at least one sequence from Israel in a global database shows genetic characteristics of Deltacron.
"These findings refute the undocumented statements that Deltacron is a result of a technical error," Kostrikis says.
Cyprus' Health Minister Michael Hadjipantela said on Sunday that Deltacron isn't of concern and more details will be given later this week.
