New Delhi: Omicron is a "deviant" from the COVID-19 pandemic progression script and so it must be postulated that two pandemics are going on side by side, one by the Delta and close relatives and the other by the latest variant of concern, said noted virologist Dr T Jacob John.
Speaking to PTI on how the pandemic can now be expected to progress, he pointed out that Omicron is not "fathered, or mothered, by Wuhan-D614G, Alpha, Beta, Gamma, Delta, Kappa or Mu and That much is for sure".
"So in my opinion, this is a variant of unknown proximal parentage but great great grandparent was Wuhan-D614G... We shall see as the pandemic progresses," John, a former director of the ICMR's Centre of Advanced Research in Virology, said.
D614G refers to an amino acid mutation in this protein that has become increasingly common in SARS-CoV-2 viruses from around the world.
"Since Omicron is illegitimate or 'deviant' from COVID-19 pandemic progression script, we must think of two pandemics going on side by side -- Delta and close relatives, and Omicron and its variants in future.
"Diseases caused by them are also different. One is Pneumonia-hypoxia-multiorgan damage disease but the other an upper/middle respiratory disease that pushes pre-existing chronic disease or old age beyond the wall," he said.
Asked if the peak of the third wave has been reached since cases have started plateauing in some places, John said metro cities started first and will finish first.
"All put together is a national epidemic," he said.
On whether the upcoming COVID-19 variants would be more infectious but less lethal, John said generally new pathogens get adapted to human hosts and in the process tend to become more infectious and less pathogenic, within limits.
"Time frame is long, not one or two years... Remember, Delta came late but was both faster-spreading and more pathogenic," he said.
Omicron, the highly infectious variant of coronavirus, is driving the third wave of COVID-19 pandemic in India.
The country registered 2,71,202 new coronavirus infections, taking the tally of COVID-19 cases to 3,71,22,164, including 7,743 cases of the Omicron variant, according to the Union Health Ministry data on Sunday....