Why did so many vaccinated people catch the omicron variant recently ?

Many people report that they have seen many of their friends and family and work colleagues have caught the COVID virus during the recent wave.

Why did so many vaccinated people catch the infection?

It’s because of two reasons. (1) the vaccines are not 100% effective and (2) there is substantial reduction in vaccines effectiveness over time.

A large U.K. study looked at vaccine effectiveness against symptomatic disease caused by the omicron and delta variants in England.

Frighteningly, No effect against the omicron variant was noted from 20 weeks after two Astra Zeneca vaccine doses, and the effectiveness of two Pfizer vaccine was only marginally better with 8.8% protection at 25 or more weeks after two Vaccine doses.

Vaccine effectiveness improved to about 65% protection at 2 to 4 weeks after a third Pfizer booster but this was not long lasting and the effectiveness decreased to about before decreasing to 44% at 10 or more weeks after Vaccination.

In summary, Vaccination with two doses of AstraZeneca or Pfizer vaccine provided limited protection against symptomatic disease caused by the omicron variant.

A third booster with Pfizer or Moderna vaccine substantially increased the protection, but even that protection gradually decreased over time.

This study, published in the Prestigious NEJM journal, was Funded by the U.K. Health Security Agency and hence highly reliable.

One has to hope that any new variants do not bypass the vaccine protection and cause much more severe disease than omicron!

References

Daily Mail. US Omicron surge is close to reaching its peak with infections ‘coming down as fast as they went up as variant runs out of people to infect’: Deaths remain low, rising just 10% in two weeks as daily cases rise 184%. By Mansur Shaheen U.S. Deputy Health Editor For Dailymail.Com
14:53, 12 Jan 2022 , updated 22:18, 12 Jan 2022

NEJM. Covid-19 Vaccine Effectiveness against the Omicron (B.1.1.529) Variant.

Nature magazine. Iketani, S., Liu, L., Guo, Y. et al. Antibody evasion properties of SARS-CoV-2 Omicron sublineages. Nature (2022). https://doi.org/10.1038/s41586-022-04594-4 ( substantial loss in neutralizing activity against omicron variant)

Disclaimer: Please note – This blog is NOT medical advice. This blog is NOT a expert medical opinion on various topics. This blog is purely for information only and do check the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you. The views expressed in this blog are NOT, in any way whatsoever, intended to be a substitute for professional advice. The blog is NOT previewed, commissioned or otherwise endorsed, in any way, by any organisation that the author is associated with. The views expressed in this blog likely represents some of the author’s personal views held at the time of drafting the blog and MAY CHANGE overtime, partic

Are COVID vaccines less effective in people with low-immunity?

Yes, the COVID vaccines struggle to boost the immunity against COVID in people who have a defective or suppressed immune system.

A recent study published in BMJ looked at all relevant publications and confirms this. Cancer patients and patients who have received organ transplants are at risk of inadequate protection from the vaccines.

It is important that people who have low immunity get boosters as recommended by the guidelines ( third or fourth dose).

References

BMJ. Efficacy of covid-19 vaccines in immunocompromised patients: systematic review and meta-analysis
BMJ 2022; 376 doi: https://doi.org/10.1136/bmj-2021-068632 (Published 02 March 2022)
Cite this as: BMJ 2022;376:e068632

U.K. govt. COVID-19 vaccination: a guide to booster vaccination for individuals aged 18 years and over and those aged 16 years and over who are at risk. Updated 2 February 2022.

NHS. Coronavirus (COVID-19) vaccine for people with a severely weakened immune system. Page last reviewed: 24 February 2022

Disclaimer: Please note – This blog is NOT medical advice. This blog is NOT a expert medical opinion on various topics. This blog is purely for information only and do check the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you. The views expressed in this blog are NOT, in any way whatsoever, intended to be a substitute for professional advice. The blog is NOT previewed, commissioned or otherwise endorsed, in any way, by any organisation that the author is associated with. The views expressed in this blog likely represents some of the author’s personal views held at the time of drafting the blog and MAY CHANGE overtime, particularly when new evidence comes to light.

How quickly do COVID vaccines lose their effectiveness?

The rapid development and deployment of COVID vaccines has played a critical role in bringing the Pandemic under control (at least in early 2022).

But there is a disappointing factor with the current vaccines. The disappointing factor is NOT the side effects !

The disappointing factor is the loss of efficacy (protection) within a matter of months, particularly against new variants.

How quickly do the vaccines lose their effectiveness?

An Italian study published in BMJ provides some insight.

In this study involving more than 33 million people, the long term protection of Pfizer-BioNTech and Moderna vaccines was assessed.

Vaccine effectiveness against any SARS-CoV-2 infection significantly decreased from 82% to 33% at about 7 months after the second dose.

Vaccine effectiveness against severe covid-19 (admission to hospital or death) was much better though. The effectiveness decreased but to a much lesser extent, from 96% to 80%.

This Italian study confirms that a booster dose of vaccine six months after the primary vaccination cycle is the best way forward.

Reference: Effectiveness of mRNA vaccines and waning of protection against SARS-CoV-2 infection and severe covid-19 during predominant circulation of the delta variant in Italy: retrospective cohort study
BMJ 2022; 376 doi: https://doi.org/10.1136/bmj-2021-069052 (Published 10 February 2022)
Cite this as: BMJ 2022;376:e069052

Disclaimer: Please note – This blog is NOT medical advice. This blog is NOT a expert medical opinion on various topics. This blog is purely for information only and do check the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you. The views expressed in this blog are NOT, in any way whatsoever, intended to be a substitute for professional advice. The blog is NOT previewed, commissioned or otherwise endorsed, in any way, by any organisation that the author is associated with. The views expressed in this blog likely represents some of the author’s personal views held at the time of drafting the blog and MAY CHANGE overtime, particularly when new evidence comes to light

To Boost or not to boost ?

U.K. has started offering booster vaccines.

People aged 50 years and over, health and social care workers and younger people at risk are being offered a booster dose of coronavirus (COVID-19) vaccine.

Firstly, it has to be pointed out that it is not uncommon to offer booster vaccines with various other viral illnesses.

Secondly, the Data from Israel does support a role for COVID booster vaccines.

On the other hand, some people feel the case for booster is overstated.

The decision by U.K. Govt seems to be a reasonable and pragmatic one considering that the rate of new COVID infections is still high.

References

Guardian Opinion
The message from Israel is clear: Covid booster shots should be standard
David O’Connor
Mon 27 Sep 2021 11.47 BST

NEJM. Protection of BNT162b2 Vaccine Booster against Covid-19 in Israel
Yinon M. Bar-On, M.Sc., Yair Goldberg, Ph.D., Micha Mandel, Ph.D., Omri Bodenheimer, M.Sc., et al.
September 15, 2021
DOI: 10.1056/NEJMoa2114255

U.K. Govt Guidance
COVID-19 vaccination: a guide to booster vaccination
Published 16 September 2021

BMJ. Editorials
Covid-19 vaccination: evidence of waning immunity is overstated
BMJ 2021; 374 doi: https://doi.org/10.1136/bmj.n2320 (Published 23 September 2021)
Cite this as: BMJ 2021;374:n2320

Daily Mail. UK’s daily Covid cases rise 5% in a week to 37,960 as hospital admissions and deaths continue to fall – amid fears FOURTH wave may have already began with cases starting to spill over from children to their parents. By Emily Craig Health Reporter For Mailonline and Luke Andrews Health Reporter For Mailonline
12:35, 27 Sep 2021 , updated 16:44, 27 Sep 2021

Disclaimer: Please note – This blog is NOT medical advice. This blog is NOT a expert medical opinion on various topics. This blog is purely for information only and do check the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you. The views expressed in this blog are NOT, in way whatsoever, intended to be a substitute for professional advice. The blog is NOT previewed, commissioned or otherwise endorsed, in any way, by any organisation that the author is associated with. The views expressed in this blog likely represents some of the author’s personal views held at the time of drafting the blog and MAY CHANGE overtime, particularly when new evidence comes to light.

Are booster vaccines the way out of this pandemic?

Vaccination promised a straightforward way out of the pandemic. Protection from TWO doses of vaccine initially promised to end the pandemic.

Israel led the way in mass vaccination. Infection rates plummeted and life seemed to be returning to normal.

But infection rates then started rising in Israel and Israel was forced to use booster vaccines for high risk population.

It is now hoped that the THIRD booster vaccines would provide a way of keeping COVID infections at a manageable level.

Only time will tell whether this strategy would be successful!

References

BBC Covid: What Israel tells us about the way out of the pandemic
By Rachel Schraer
Health reporter

Sky News. COVID-19: Scientists say vaccines could control pandemic … After two doses of Pfizer, there was a 70% reduction in all cases and a 90% drop in symptomatic cases, new data shows. Friday 23 April 2021 09:08, UK

Disclaimer: Please note – This blog is NOT medical advice. This blog is NOT a expert medical opinion on various topics. This blog is purely for information only and do check the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you. The views expressed in this blog are NOT, in way whatsoever, intended to be a substitute for professional advice. The blog is NOT previewed, commissioned or otherwise endorsed, in any way, by any organisation that the author is associated with. The views expressed in this blog likely represents some of the author’s personal views held at the time of drafting the blog and MAY CHANGE overtime, particularly when new evidence comes to light.