Quote:First, it seems that infection by one or other of Delta and Omicron does not guard against protection from the other – so there is plenty of scope for the variants to exist side by side.

And second, Omicron appears to evade vaccines much more successful – although not so much if they’re accompanied by booster or previous infection.

This raises the possibility of Delta continuing to infect large numbers of unvaccinated people, while Omicron sweeps through people who have had one or two jabs, as well as infecting some unvaccinated people.

Professor Paul Hunter, of the University of East Anglia, who is not a member of Sage, said: “We may have two simultaneous epidemics, one from Omicron and one from Delta.”

“This raises the concern about Delta and omicron coinfections, where both variants infect the same person at the same time. In general coinfections of any respiratory viruses are associated with more severe disease and we certainly saw that early in the pandemic with covid and influenza coinfections,” he said.

“The booster vaccine campaign will be more effective against Delta and we may see cases of Delta starting to fall because of immunisation rather than Omicron.”

“Nevertheless we need to be aware of the potential for coinfection with Delta and Omicron. If coinfections become a problem this could have significant implications for management and for control of infection in hospital,” Professor Hunter said.

One way segregation might occur is if Delta continued to spread in unvaccinated populations such as young children, as cases are currently very high among primary school children.

At the same time, Omicron could spread more easily in those with some immunity from Delta and other covid strains, for example younger people who are unvaccinated but were infected six or more months ago, or people who were double-vaccinated four to six months ago.

It is expected that Omicron will eventually replace Delta but this is unlikely to be for some time.

Stephen Griffin, a virologist from Leeds University, said: “It’s certainly possible that we could have two epidemics. You could certainly see segregation.”

“Delta is more restricted to school children because the majority of adults are vaccinated, so it really depends how well Omicron spreads in fully vaccinated and boosted populations,” he said.

(11-12-2021, 08:46 PM)luncheonmeat Wrote:  With Covid, one variant doesn't preclude the infectee from catching another. Jin scary. Hope omicron is as mild as they are so far seeing.