UK Omicron emergency announced

Omicron emergency https://www.bbc.co.uk/news/uk-59631570 No one should be in any doubt, there is a tidal wave of Omicron coming It is now clear that two doses of vaccine are simply not enough to give the level of protection we all need. But the good news is that our scientists are confident that with a third dose, a booster dose, we can all bring our level of protection back up At this point our scientists cannot say that Omicron is less severe a wave of Omicron through a population that was not boosted would risk a level of hospitalisation that could overwhelm our NHS and lead sadly to very many deaths Aged 18 and over, in England, third jabs from this week Three months since second dose A third booster dose prevents around 75% of people getting any Covid symptoms from Omicron Live data, hospital patients who have tested positive https://www.nicd.ac.za/diseases-a-z-index/disease-index-covid-19/surveillance-reports/daily-hospital-surveillance-datcov-report/ Omicron cases have now been found in hospital Nadhim Zahawi Warned of the danger of tens of thousands of hospitalisations, even if omicron were to prove half as severe as delta SARS-CoV-2 variants of concern and variants under investigation in England Technical briefing 31 https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1040076/Technical_Briefing_31.pdf Data cut off, 6 December 260 confirmed cases of Omicron VOC-21NOV-01 (B.1.1.529), Identified through sequencing or genotyping in England. Additional possible cases identified through S gene target failure Higher risk of transmission from secondary attack rates Risk of household transmission from an Omicron index case compared to a Delta index case 3.2 Risk of a close contact becoming a secondary case, adjusted odds ratio 2.09 Household secondary attack Omicron, 21.6% Delta, 10.7% Three to eight-fold increased risk of reinfection with the Omicron variant. A 20 to 40-fold reduction in neutralising activity by Pfizer 2-dose vaccinee sera for Omicron At least 10 fold loss of activity when compared to Delta Greater reduction in activity was seen for AZ 2- dose sera An mRNA booster dose resulted in an increase in neutralising activity irrespective of primary vaccination type Data are urgently required on the durability of neutralising activity A moderate to high vaccine effectiveness of 70 to 75% is seen in the early period after a booster dose. With previous variants, vaccine effectiveness against severe disease, has been higher than effectiveness against mild disease Lateral flow, similar sensitivity to detect Omicron compared to Delta Modelling the potential consequences of the Omicron SARS-CoV-2 variant in England https://cmmid.github.io/topics/covid19/omicron-england.html https://www.bbc.co.uk/news/uk-59621029 Growth rate of the Omicron variant Level of immune escape Intrinsic transmissibility Immune escape of Omicron 5.1-fold to 12.8-fold reduction in neutralisation relative to Delta Intrinsic transmissibility Omicron variant is growing in England at an exponential growth rate of r = 0.29 per day This corresponds to a 2.4-day doubling time Reproduction number Rt = 4.0 Generation interval of 5.5 days Surge in SARS-CoV-2 transmission beginning in late December 2021 Infections exceeding peak levels recorded during the January 2021 wave in England The most optimistic scenario, 1 December to 30 April in England Omicron has low immune escape and booster jabs are highly effective 20.9 million infections 175,000 hospital admissions 24,700 deaths Most pessimistic scenario, 1 December and 30 April in England 34.2 million infections 492,000 hospital admissions 74,900 deaths Conclusions and discussion Without the implementation of further control measures, hospital admissions resulting from the Omicron wave of transmiss