According to Government scientists, Omicron infected Brits have three times the risk of spreading Covid to their family members than those who are Delta-infected.
The pandemic is being driven by household transmission. Up to 43% of all infections are believed to have been caused in households.
According to the UK Health Security Agency the super mutant strain of the virus has even greater transmission advantages.
According to the UKHSA, 140 of the 777 Omicron cases confirmed in England by December 12th would have been infected (18%)
A report showed that six percent of all cases in Britain of this variant were reinfections. Government modeling estimates that the strain has a five-and-a half-time greater chance of reinfecting than Delta.
Some 305 out of 5,153 Omicron-positive people were diagnosed with an infection that was confirmed between November 1, 11 and 11. They had been infected at least 90 day before they tested positive.
It also revealed that the lowest number of infections as per December 12, 2012 in England, was among women in their 20s.
A UK Health Security Agency report showed six per cent of all confirmed cases of the variant in the UK are reinfections. Between November 1, 2011 and December 11, 2011, 5,153 Omicron cases were confirmed. 305 of these were confirmed infections and had not tested positive for Omicron before. Figure: Weekly rate of potential reinfections in England (blue lines).
It also revealed that the lowest-infected group as of 12/12 in England had been women in their 20s
The graph shows Omicron confirmed cases by status of travel in England, December 12-12. While most of the cases came from abroad at first (green), domestic cases quickly took over (pink). The vast majority are now being handled by people without known traveller status (purple).
The graph shows Omicron cases in England by region up to December 12. London (light blue), accounts for the largest proportion of confirmed cases of this variant.
All infections were more common among women than those of men (523) than in any age group. Women accounted for 50% more than the other groups (523), 419 and 418 respectively, and nearly twice that of men (30).
It has led to cases spiralling across the UK. The infection is now increasing among those over 60 in Omicron Epicentre London.
Wales has announced additional restrictions today. Mark Drakeford from Wales said that he would crack down on social gatherings, and close nightclubs starting Boxing Day. Scots will be urged to keep their mix to 3 households, and Englanders are to “prioritise” social events.
According to Neil Ferguson, Professor Lockdown today’s grim modelling suggested that there might be up to 5,000 Covid death per day in this winter with no restrictions.
The UKHSA studied 116,186 Covid cases from November 15 to December 6, of which 115,407 were Delta and 777 were Omicron.
A total of 18% of Omicron-related cases infected people in their household. This compares to 10% of Delta cases.
Omicron is statistically more likely to spread the strain than Delta.
Data were adjusted to account for gender, age, sex and race.
However, experts stated that they need more data to reach stronger conclusions and added that they would continue their analysis once further cases have been identified.
It was reported that an Omicron Index case had a lower adjusted probability of household transmission than a Delta index case.
These preliminary results suggest Omicron has an advantage in transmission over Delta.
This analysis could be affected by Omicron case ascertainment. To improve accuracy, the analysis will be repeated.
Omicron also appears to be increasing the risk of reinfection and first infection.
There were six cases of Omicron that had been infected before, and four others who have experienced Omicron as their third infection.
It was also found that LFD (lateral flow) tests were as effective in detecting Omicron viruses as any other coronavirus variants.
HSA chief executive Dr Jenny Harries stated: “Our data show that LFD tests can detect Covid-19 in people who have been exposed Omicron, as well in persons exposed to other variants.” This is great news.
“As all of us work to minimize the spread of this variant in the Christmas period we encourage people to regularly test, particularly prior to attending social gatherings.
“As usual, the booster vaccine continues to provide the greatest protection against infection. We ask that you come forward as quickly as possible to get your booster.
A separate report by Imperial College London today revealed that Omicron’s risk of reinfection is 5.4% higher than the Delta variant.
This indicates that Omicron’s protection from reinfection due to past infections may only be 19%.
The Omicron severity was not lower than Delta’s, however data regarding hospital admissions were very low during the research.
Data suggests that boosters are essential in Omicron control, although they could lose effectiveness with time.
Researchers estimated the proportion of Omicron among all Covid cases between November 29 and December 11 was doubling every two days up to December 11.
This is how they calculated the Omicron reproduction number (R). It was also higher than 3, during the study period.
Professor Neil Ferguson of Imperial College London commented: “This study adds to the evidence that Omicron has the ability to evade previous immunity from both vaccination and infection.
Omicron is a serious threat to the public’s health because of its immune evasion.
According to the report, there’s a significant increase in risk for Omicron cases among those two or more week after receiving their second dose of vaccine and two or three weeks before their booster dose.
Based on the vaccine effectiveness estimations against symptomatic Omicron infections from the Delta variant vaccine effectiveness rates translate into vaccine effectiveness assessments against symptomatic Omicron infection between zero percent and 20% after two doses and between 55% and 80% after a booster.
Researchers used the data of both NHS and UKHSA to confirm all confirmed PCR-confirmed Covid cases from England. They were taken between November 29th, 2012 and December 11.
Professor Azra Khani from Imperial College London said that despite the fast spread of Omicron, the possibility exists that it will eventually replace the Delta variant worldwide in the next weeks.
Emerging immunogenicity data show significant decreases in neutralising antibody levels, while preliminary estimates of vaccine efficacy demonstrate substantial protection against mild diseases.
According to our estimates, this could lead to a small but substantial decrease in effectiveness against severe diseases and death.
“One question that remains unanswered is whether the Omicron variant will cause more severe disease than previous Omicron variants.