Omicron is surging, but may cause less severe illness

The Omicron variant, discovered almost a month ago in South Africa, sparked fears all over the globe, due to its extremely high contagiousness and ability to partly evade protection from previous infection or vaccination. It is currently surging through Europe and the United States, driving daily cases past Delta’s peaks in many countries.

However, data from South Africa, Omicron’s original epicenter seem to give reason for optimism. According to the country’s top scientists, South Africa may have already passed the peak of its Omicron outbreak, much faster than it happened in the case of previous variants, such as Delta or Beta. 

As of December 18, although the test positivity remained still high (at 29.8 precent), there has been a 20.8 percent decrease in the number of new detected cases. Moreover, the rates of hospitalization and deaths have also been significantly lower relative to those experienced in previous waves.

New studies from Scotland and England have also suggested that Omicron might be milder than Delta in terms of severe cases that lead to hospitalizations and deaths. Initial estimates from Imperial College London show that, compared with Delta variant cases, people infected with Omicron are 15 to 20 percent on average less likely to end up in hospitals. However, it is not yet clear whether the mildness of many Omicron cases is caused by intrinsic characteristics of the virus or the fact that many positive cases are breakthrough infections or reinfections.

A new study led by the University of Hong Kong has found that while Omicron multiplies 70 times faster than Delta in the human bronchus, making it more transmissible through droplets and aerosols, it spreads ten times slower in the lungs, and thus less likely to cause severe cases of pneumonia. Although these findings may indeed suggest that this variant is milder, study lead author Dr Michael Chan Chi-wai warns that, due to its high transmissibility, Omicron might still cause a significant amount of damage.

“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. Therefore, taken together with our recent studies showing that the Omicron variant can partially escape immunity from vaccines and past infection, the overall threat from the Omicron variant is likely to be very significant,” he concluded.  

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By Andrei Ionescu, Earth.com Staff Writer