WHO says Omicron is evading some immune responses
The Omicron variant of the coronavirus is spreading faster than the Delta variant and is causing infections in people already vaccinated or who have recovered from the COVID-19 disease, the head of the World Health Organization (WHO) said on Monday.
Soumya Swaminathan, Chief Scientist, WHO added it would be “unwise” to conclude from early evidence that Omicron was a milder variant that previous ones. The variant is successfully evading some immune responses meaning that the booster programmes being rolled out in many countries ought to be targeted towards people with weaker immune systems.
Tedros Adhanom Ghebreyesus, Director General, WHO said, “There is now consistent evidence that Omicron is spreading significantly faster than the Delta variant. And it is more likely people vaccinated or recovered from COVID-19 could be infected or re-infected.”
Their comments echoed the finding of study by Imperial College London, which said last week the risk of reinfection was more than five times higher and it has shown no sign of being milder than Delta. WHO officials said however that other forms of immunity vaccinations may prevent infection and disease. While the antibody defences from some actions have been undermined, there has been hope that T-cells, the second pillar of an immune response, can prevent severe disease by attacking infected human cells.
Abdi Mahamud, WHO expert added, “Although we are seeing a reduction in the neutralisation antibodies, almost all preliminary analysis shows T-cell mediated immunity remains intact, that is what we really require.”
However, highlighting how little is known about how to handle the new variant that was only detected last month, Swaminathan also said, “Of course there is a challenge, many of the monoclonals will not work with Omicron.”