[Lewis Thomson (OP)]

Nigel would like some help finding answers to this question.

"In the UK it is being reported that there is a doubling of Covid infection rate (presumably all due to the new variant Omicron) every 2-3 days. What I would like to know is how many of these people have received 3 vaccinations including the Pfizer booster. In other words, how much protection is "full vaccination" currently providing?"

Can you help him? Leave your answers in the comments below...

[alancalverd]

Not a doubling of the rate, but of the number of infections. This is entirely normal in the early phase of any new or mutated viral epidemic, and given consistent social interactions, the doubling time depends on the infectivity of the new bug.

The statistics are still fluid but the general finding is that full vaccination provides a high probability of not being infected by the original virus, and not suffering severe symptoms from the variants.

The only certain "live" statistic is the fraction of people hospitalised  with COVID symptoms who have not been vaccinated. Currently these account for 90% of ICU COVID cases, so given that about 90% of the most vulnerable have had at least two jabs, one should conclude that  full vaccination renders you 100 times less likely to suffer severe symptoms.

[evan_au]

Many people in the UK were vaccinated with the Astra-Zeneca vaccine, which turned out to be rather ineffective against Omicron variant - so it is important that people who received Astra Zeneca also receive an RNA vaccine booster (like Pfizer or Moderna).
- Australia took a mixed approach, and presumably those who received 3 doses of RNA vaccine (generally younger) are better protected than those who had 2 doses of Astra-Zeneca, plus one of RNA vaccine (generally older people). Raw numbers around here suggest that if you have had 3 doses of vaccine (and allow the third dose to take effect - about 2 weeks) are something like 10 times less likely to end up in ICU than unvaccinated people.
- It is hard to compare raw numbers, because the people who are older are far more susceptible and (wisely) got vaccinated in far greater numbers than younger people who are less susceptible, and so (boldly) decided to avoid the vaccine. To get a real indication of the vaccine effectiveness, you need to compare the mortality of old people who were/weren't vaccinated, and also young people who were/weren't vaccinated; comparing old people who were vaccinated against young people who weren't vaccinated will give a misleading indication of vaccine effectiveness.

a doubling of Covid infection rate (presumably all due to the new variant Omicron) every 2-3 days

The exponential growth phase of Omicron infections has now passed in the UK, and new infections are dropping rapidly. There is a lag of around a month from initial infection to ICU and death, but even deaths are now falling in UK.

What is not clear to me is the growth rate of the less-infectious Delta variant, which may be growing slowly, disguised by the fall in Omicron numbers.

A useful website (also covers most other countries): https://ourworldindata.org/coronavirus/country/united-kingdom

We can't predict when the next wave will occur (new variants are being generated continuously), or to what extent it will bypass existing vaccines - watch this space!

[set fair]

  full vaccination renders you 100 times less likely to suffer severe symptoms.

Concur. I heard the figure 97% less likely to die from Omicron if your boosted, compared to unvaccinated and not previously infected of whom there will soon be less than a million, in the UK.