By Babalola Seyi
There is mounting evidence that the novel omicron coronavirus variation is capable of quickly spreading in populations with immunity to existing coronavirus variants. It has already infiltrated numerous nations and looks to be on track to inflict a massive outbreak of illnesses worldwide.
The big unknown is whether omicron causes more or less severe disease and death. According to Aris Katzourakis of the University of Oxford, he is skeptical that the variant’s alterations would result in reduced severity, but it is too early to know.
“We’re all concerned,” Katzourakis adds. “We’re keeping our fingers crossed.”
Cases are increasing much faster in South Africa, where the variation was initially discovered, with case counts doubling every three to four days.
The fast expansion in South Africa is not necessarily indicative of what may occur elsewhere. The beta variety that was discovered in South Africa and produced the virus’s second wave did not generate similar surges in cases in other countries. However, there are indications that omicron is already taking off in other nations.
In the United Kingdom, for example, there is a dramatic increase in so-called S-gene dropouts in PCR covid-19 testing, a condition that occurs when a variation has particular mutations in the gene encoding its spike protein. This is most likely due to omicron. Denmark, which does extensive sequencing, has already identified approximately 200 instances of covid-19 caused by this variant.
The main reason omicron is spreading so quickly appears to be its ability to evade prior immunity. Researchers in South Africa discovered that omicron has a much higher risk of reinfection. This implies that the chance of vaccinated persons being sick is substantially higher than with delta. This is supported by preliminary case reports. For example, six of the 11 omicron cases reported in Israel so far have involved persons who had received three doses of the Pfizer vaccine.
Aside from the possibility of evading immunity, omicron may be fundamentally more transmissible than delta. This is yet unknown, but there have already been three reports of superspreading incidents in which an unusually high number of people were infected at parties in Norway, Denmark, and the United Kingdom.
The good news is that those who are sick despite vaccination or past infection are expected to be less likely to get extremely ill than those who have no prior protection, as with delta. This is because, while omicron may elude antibodies, it is far more difficult for it to evade immune cells called T-cells, which assist in clear viral infections. We also have considerably better therapies now, however, these are mostly available in wealthy nations.
Because of the time lag between people becoming infected, becoming seriously ill, and recovering or dying, it could be several weeks before it is clear how well vaccination or prior infection will protect against severe disease, and how severe omicron will be in those who have no prior immunity.
During a press briefing on 3 December, Waasila Jassat of South Africa’s National Institute for Communicable Diseases stated that the country has already observed a significant spike in hospitalizations across all age groups. Notably, children under the age of five were the second-largest category, trailing only those over the age of 60.
We’ll have to wait and see how those in the hospital fare. As of 2 December, one South African hospital reported that fewer covid-19 patients than usual required oxygen, but cautioned that it is too early to make conclusions.