Link to free download of my 2 textbooks
http://159.69.48.3/
Physiology book in hard copy
https://www.ebay.co.uk/itm/154770452796?mkevt=1&mkcid=16&mkrid=710-127635-2958-0
Pathophysiology book in hard copy
https://www.ebay.co.uk/itm/154770451780?mkevt=1&mkcid=16&mkrid=710-127635-2958-0
US variants data
https://covid.cdc.gov/covid-data-tracker/#variant-proportions
https://www.nytimes.com/interactive/2022/01/22/science/charting-omicron-infection.html
US omicron history
November 29
Index patient, 48 year old unvaccinated man, Nigeria
Nebraska, 6 people diagnosed by PCR and genomic sequencing
Onset was 73 hours (range = 33–75 hours)
Incubation period
https://www.cdc.gov/mmwr/volumes/70/wr/mm705152e3.htm
Original version, five days
The Delta variant, four days
Omicron, 2 to 3 days
Viral Load
https://www.nejm.org/doi/full/10.1056/NEJMc2102507
Alpha and Delta variants
Peak viral load 3 days after infection
Clear the virus about six days after that
Infectious viral load in unvaccinated and vaccinated patients infected with SARS-CoV-2 WT, Delta and Omicron
https://www.medrxiv.org/content/10.1101/2022.01.10.22269010v2.full.pdf
Omicron and Delta produced similar levels of infectious virus
Infections a day shorter with omicron compared to delta
Omicron infects upper airways as opposed to lungs
Omicron antibodies neutralise delta virus
Offshoot of Omicron variant, England
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1046614/12-january-2022-risk-assessment-SARS-Omicron_VOC-21NOV-01_B.1.1.529.pdf
https://www.theguardian.com/world/live/2022/jan/22/coronavirus-live-japan-and-taiwan-report-omicron-surges-ireland-lifts-restrictions
BA.2 may be even more contagious than original omicron
UK Health Security Agency
Designating BA.2 a variant under investigation
increasing numbers of BA.2 sequences identified both domestically and internationally
May have an increased growth rate over BA.1
Vaccine effectiveness with omicron
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1048395/technical-briefing-34-14-january-2022.pdf
After a 2-dose primary course of vaccination
Vaccine protection against mild disease has largely disappeared by 20 weeks after vaccination
After a booster dose
Protection initially increases to around 65 to 70%
but drops to 45 to 50% from 10+ weeks
Therefore
It is therefore likely that current vaccines offer limited long-term protection against infection or transmission.
Protection against severe disease
Vaccine effectiveness against hospitalisation is estimated at 92%
and remains high at 83% 10+ weeks after the booster dose
John’s booster
20th November
So my protection against hospitalisation goes down from 92% to 83% by soon
Source