The omicron coronavirus strain is three times more infectious for people who have had COVID-19 than the beta and delta strains. This is stated in the preprint of a study conducted by the South African Center for Epidemiological Modeling and Analysis DSI-NRF.
The study took into account data from March 4, 2020 to November 27, 2021, collected by the South African Ministry of Health. As the AFP agency clarifies, this is the first epidemiological evidence that the immunity obtained after the transferred coronavirus may not protect against the omicron-strain disease.
According to the study, as of November 27 in South Africa, out of 2.8 million coronavirus cases, 35,670 people were re-infected. The authors of the preprint conclude that with the omicron strain, the risk of primary infection decreases and the risk of re-disease increases.
“The data obtained show that the omicron strain is largely able to bypass the immunity from COVID-19 received by those who have been ill … It remains unknown whether the omicron can bypass the immunity received from the vaccine, and how the reduced immunity can protect against severe disease and death. “, – the document says.
Juliet Pulliam, Director of DSI-NRF South Africa, posted in Twitter several graphs compiled by scientists, which tracked the incidence of “omicron”. She clarified that most of those who recently contracted COVID-19 again also had a delta strain of the virus.
Anne von Gottberg, an expert at the South African National Institute for Infectious Diseases, said that scientists expect an increase in COVID-19 cases due to the new strain. “We believe that vaccines can protect against severe disease,” she said at a press conference at the World Health Organization on the eve of December 2.
The first cases of infection with “omicron” were recorded in African countries in November, those with the new strain have already been identified in Australia, Great Britain, Germany, Israel, Spain, Italy, the United States and several other countries. Since November 28, Russia has restricted the entry of foreigners from South Africa, Hong Kong, Botswana, Lesotho, Namibia, Zimbabwe, Mozambique, Madagascar, Eswatini. All arrivals from South Africa will also have to undergo a two-week quarantine.
Read more about the new strain in the publication of the Science supplement.
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