Omicron multiplies 70 times faster but is less severe, study says

The supercharged speed of Omicron's spread in the human bronchus was found 24 hours following infection. PHOTO: REUTERS

HONG KONG (BLOOMBERG) - The Omicron variant replicates around 70 times faster than Delta and the original Covid-19 strain, though the infection severity is likely to be much lower, according to a University of Hong Kong study that adds weight to the early on-ground observations from South African doctors.

The supercharged speed of Omicron's spread in the human bronchus in the lower respiratory tract was found 24 hours following infection, according to a Wednesday (Dec 15) statement from the university.

The study, conducted by a team of researchers led by Dr Michael Chan Chi-wai, found that the newest variant of concern replicated less efficiently - more than 10 times lower - in human lung tissue than the original strain, which may signal "lower severity of disease".

The study, which suggests that Omicron jumps faster from one person to another but does not damage lung tissues as much as its predecessor strains did, is currently under peer review for publication in a scientific journal. Bloomberg did not have access to the entire study.

With scientists racing to determine how transmissible, virulent and evasive Omicron is - it has already travelled to at least 77 nations within three weeks of being first detected in southern Africa - the new research out of Hong Kong may add ballast to descriptions by some physicians that most infections have so far been mostly mild and not requiring hospitalisations.

Many researchers are now watching if the most mutated coronavirus variant will crowd out other strains and pave way for the pandemic to become endemic, where the world learns to live with the pathogen.

Early observations have shown that most patients do not need oxygen or intensive treatment for the illness, but many public health experts and bodies, including the World Health Organisation, have urged caution.

Many breakthrough and re-infection cases have been found along with infection in young people with no significant risk factors. Countries across the world have reacted with urgency and wariness, erecting travel barriers amid widespread fears that Omicron will prompt new surge in infections and add to the burden of hospitals.

Even if Omicron is conclusively proved to be less severe, its wildfire spread can stretch and challenge health facilities around the world. The university's study also warns against taking the new variant lightly.

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"By infecting many more people, a very infectious virus may cause more severe disease and death even though the virus itself may be less pathogenic," Dr Chan said in the statement.

Given that the Omicron variant can partially escape immunity from vaccines and past infection, "the overall threat from omicron variant is likely to be very significant".

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