‘No evidence’ softer than Omicron Delta, British researchers say Coronavirus pandemic News
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British investigators say they have not found any “evidence” Omicron coronavirus variant It’s softer than Delta, he doubts cautious optimism some experts believe that the new strain may not be so virulent and that it will not go beyond the health system.
An investigation by Imperial College London (ICL) on Friday – when British officials reported a record number of COVID-19 cases for the third day in a row, rising to 93,045 new infections – also found that the risk of infection with Omicron was more than five. Times higher than Delta.
The same study was not based on data from the UK Health Safety Agency and the National Health Service in a PCR test on people who tested positive for COVID-19 in England from 29 November to 11 December.
“We do not find that Omicron has a different severity in the Delta (hospitalization risk and symptom status),” the study said, although data on hospitalizations remain very limited.
“By controlling vaccine status, age, sex, ethnicity, asymptomatic status, region, and sample date, Omicron was again associated with a 5.4-fold higher risk of infection compared to Delta,” the December 16 study added.
In South Africa, whose scientists first identified Omicron last month, initial anecdotal accounts have suggested that the new variant causes less serious disease than its predecessors, but scientists say it is too early to draw firm conclusions.
The country reported a record number of daily infections earlier this week.
“We believe that Omicron may not be less virulent, but … vaccine coverage [and] … is adding protection to the natural immunity of people who have already been exposed to the virus, “said Health Minister Joe Phaahla. say press conference on Friday. “That’s why we’re seeing mild illnesses.”
However, the ICL said in a statement that the protection against past infections with Omicron could be as high as 19 percent, according to its study.
The study, involving AstraZeneca and Pfizer vaccines, also found that the risk of developing a symptomatic case of Omicron was significantly higher compared to Delta, two weeks or more after the second dose and two weeks or more after the booster dose.
According to estimates used for the effectiveness of the vaccine against symptomatic infection of the Delta variant, this becomes the vaccine efficacy between 0 percent and 20 percent after two doses, and between 55 and 80 percent of a booster dose.
“This study provides further evidence that Omicron can prevent previous immunity to infections or vaccines,” said Professor Neil Ferguson in a statement to the ICL.
“This level of immune leakage means that Omicron is a major and immediate threat to public health.”
But Dr Clive Dix, the former chairman of the UK Vaccine Group, said it was important not to interpret the data.
“The conclusions are based on making hypotheses about Omicron, where we don’t have enough data yet,” Dix said. “For example, we don’t have data on the cellular immune response, which is now probably boosting the effectiveness of vaccines.”
He added: “This is a crucial hypothesis that is missing from the model.”
Some of the findings are different from data from South Africa, where vaccines are now holding up well against serious illness and death, he said.
“There is a lot of uncertainty in these modeled calculations and we can be sure of the impact of the promoters against Omicron when we have another real-world month of hospitalization ICU numbers and deaths,” he said.
A study by SIREN in the UK on the risk of re-infection in healthcare workers, conducted before the creation of Omicron, found that a first coronavirus infection offered 85 per cent protection from a second over the next six months.
The data analyzed by the ICL were based on 333,000 cases, which were confirmed as a variant of Omicron coronavirus 122,062 and 1,846 in the Delta by genome sequencing.
The new findings could speed up the imposition of stricter restrictions in several European countries in order to halt the spread of the new variant.
“Due to the rapid spread of the Omicron variant so far, it is now very likely that it will replace the Delta variant that is circulating in the coming weeks worldwide,” said ICL professor Azra Ghani.
“One of the remaining uncertainties is the severity of the disease caused by the Omicron variant compared to the disease caused by the previous variants. as part of a broader response “.
Meanwhile, the UK Health Security Agency said Omicron cases were doubling in less than two days in all parts of England except the south-west. The variant is already estimated to account for more than 80 per cent of new cases in London.
The variant has not caused much hospitalization or death yet, although it has always been between infection and serious illness.
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