Why is Omicron spreading so fast?

Analysis

Speed of Transmisson

Omicron appears to be spreading faster in part because it is more efficient in airborne transmission, meaning that only a relatively short period of exposure is sufficient to catch the virus. Also it appears to evade vaccines as a preventative (especially with just two shots and no booster) even more effectively than Delta, giving it a larger pool of people for potential infection.

It is still unclear if it is less severe, but it does seem so far than even two doses of vaccine can prevent severe infection. Unfortunately, until good statistics of sufficient magnitude are available which differentiate between (a) type of Covid, Omicron or not (b) vaccine status of individuals, we will have no idea as to whether it really is "mild" or just less so among the vaccinated. We also need to know how it effects people with a third factor (c) age, as we know efficacy of vaccines and severity of Covid is very age related. 

Genomic Sequencing and Data Analysis.

For the small numbers involved, it would help if Jersey could track hospitalisations by Covid variant, vaccine status and age, and any underlying medical conditions, and that would help produce a sounder picture of what is happening locally. There is no reason why such information should not be public as it will help people assess their own personal risk, something the goverment is always telling us to do.

Border Controls

The speed of transmission suggests that if it will soon get into Jersey. Vaccinated travellers are not given PCR tests or lateral flow tests on arrival at the airport, and the chances are therefore great that the virus will enter through this gap in detection, especially as we know it can infect vaccinated individuals.

Vaccine Passports

The need for extra boosters, perhaps every six months, mean that vaccine passports must be both electronic or capable of linking to an electronic database (QR codes) so that they can be updated or go out of date, just as travel passports do. No one yet seems to have addressed this issue. But clearly vaccine protection wanes over time, boosters are needed for variants, and a passport that is purely static will effectively be out of date.

Interestingly, the UK government has just announced three jabs - two and booster - are now needed for full vaccination status. That still assumes a static model, and I'd sooner see a date related expire on passports - which could include boosters - as this would address vaccine waning.

Sources and selected extracts

Our preliminary analyses suggest that the rapid growth of this variant is due to a combination of immune evasion and higher transmissibility.

We do not yet know much about the severity of disease caused by this variant. My expectation is that it will generally be milder in people with a history of previous infection or vaccination. However, people with no form of protective immunity may experience similar patterns of disease severity as has been seen with earlier variants. I think it would be wise to prepare for a worst-case scenario in terms of hospital planning.

Read more at:
https://economictimes.indiatimes.com/news/india/view-omicron-variant-will-spread-very-rapidly-in-india/articleshow/88247314.cms?utm_source=contentofinterest&utm_medium=text&utm_campaign=cppst

In their statement, the chief medical officers said early evidence shows the Omicron variant is spreading much faster than Delta - and that vaccine protection against symptomatic disease from Omicron is reduced.

"Data on severity will become clearer over the coming weeks but hospitalisations from Omicron are already occurring and these are likely to increase rapidly.

https://www.bbc.co.uk/news/uk-59629916

CCTV footage from a hotel in Hong Kong has triggered concerns. According to a report published by researchers at the University of Hong Kong in the journal Emerging Infectious Diseases, the Omicron variant has spread among two fully vaccinated travellers across the hallway of a Hong Kong quarantine hotel, highlighting why the highly mutated coronavirus strain is unnerving health authorities. As per the report, the CCTV footage showed neither person left their room nor they had any contact, yet the travellers contracted Omicron variant, leaving airborne transmission as a cause of concern. The researchers also said that most probable mode of spread of infection must be when respective doors were opened for food collection or Covid testing was being done.

https://swachhindia.ndtv.com/explained-how-quickly-does-omicron-spread-what-is-the-severity-of-the-disease-65373/

"Personally, I'm reevaluating plans for the holidays," Bronwyn MacInnis, director of pathogen genomic surveillance at the Broad Institute of MIT and Harvard University, said on a call with reporters Tuesday. "It's the responsible thing to do and what feels right given the risk."

She and a handful of other Massachusetts-based researchers on the call said they've been stunned by the pace by which omicron has been crowding out other variants and taking over the pandemic.

"Personally, I'm reevaluating plans for the holidays," Bronwyn MacInnis, director of pathogen genomic surveillance at the Broad Institute of MIT and Harvard University, said on a call with reporters Tuesday. "It's the responsible thing to do and what feels right given the risk."

She and a handful of other Massachusetts-based researchers on the call said they've been stunned by the pace by which omicron has been crowding out other variants and taking over the pandemic.

While previous variants popped up in one country and then another, "you could watch it unfold from place to place to place," Lemieux said, omicron "seems to be happening every place at once."

Hospitalization rates are still lower with omicron than with earlier waves and patients are less likely to require ventilation, though it’s not clear whether that’s because of the newness of the variant, because it is less dangerous, or because prior infections and vaccinations provide protection. MacInnis and the others said. About 16% of South Africans hospitalized with COVID-19 have been vaccinated.

https://www.usatoday.com/story/news/health/2021/12/14/covid-variant-omicron-worries-experts/8898798002/