UK has reported over 50% rise in weekly Covid cases while daily infections in South Africa have swelled by 75-times since the start of November.
While the cases in South Africa are expected to peak very soon, the nascent experience with this new, highly transmissible variant has given the world some clues about the course of the pandemic in the coming days.
How big of a threat is Omicron?
Daily Covid infections in South Africa may have surged rather quickly due to the new variant, but there has been no corresponding rise in deaths or even hospitalisation.
According to early data, hospitalisation in South Africa is significantly lower compared to previous waves of Delta variant. Moreover, there has not been a single Omicron-linked death in the country even though it has been nearly a month since the first cases were detected.
The graph above shows the case trajectory of Omicron-hit South African province of Gauteng.
The figures clearly indicate that in all the previous waves, South Africa witnessed a corresponding rise in both hospitalisation as well as death.
Omicron may replace Delta
Several experts have predicted that the rate at which it is spreading, Omicron will gradually replace the dominant Delta strain which had triggered mayhem in several parts of the world.
While Delta is still the dominant strain in many countries, the fast-spreading Omicron is quickly going to overpower the previous variant.
Courtesy: Trevor Bedford | Twitter
Virologist Dr Trevor Bedford has graphed the cases by variant type and country.
The graph shows that Omicron is clearly the dominant variant in South Africa and is on its way to surpass the Delta strain in several other countries.
How Omicron is different from Delta
The unprecedented pace at which Omicron is spreading has certainly stoked fears. Experts believe that cases could soar as much as the testing capacity of some nations, something that has not been witnessed during a pandemic yet.
A group of scientists in Hong Kong took human tissue from the bronchus and lung and infected it with Omicron.
They measured how quickly the virus replicated compared to other variants like Delta.
Courtesy: University of Hong Kong
They found that 24 hours after infection, Omicron replicated 70 times higher than the Delta variant and the original SARS-CoV-2 virus in the bronchial tissue.
However, Omicron replicated less efficiently (10 times lower) in lung tissue than the original SARS-CoV-2 virus, which may contribute to less severe illness.
Moreover, the findings indicate that Omicron is also partially escaping vaccine immunity and infection-induced immunity.
Thus, while vaccines offered a fair degree of protection to those infected with Delta, they would do little to prevent Omicron from affecting people.
The only hope therefore rests on the severity of the disease caused by the new strain. The explosion of cases are bound to increase hospitalition – something both South Africa and UK are witnessing – but if deaths continue to remain low and past immunity holds, then Omicron may not pose as big a threat as Delta.
In fact, there are some expert predictions that if Omicron does replace Delta as the dominant strain, the world may enter the stage of endemicity.
Nevertheless, the potential surge in fresh cases is sure to keep countries on the edge as they look to prevent the devastation seen during the Delta wave.
Several European nations have already imposed strict holiday restrictions and are considering new lockdowns to stem the spike in cases.
Moreover, there is still no clarity whether the booster doses will actually help in fighting off Omicron. Initial results show that while vaccines based on new mRNA technology like Pfizer and Moderna are effective, others like Covishield and China’s Sinopharm may not offer much efficacy against the contracting the infection.