Tag: Efficacy

Pfizer COVID Vaccine: How much efficacy is lost every month?

COVID vaccines lose some efficacy over time.

How much ?

Pfizer vaccine has been reported to lose, on average, about 3% efficacy every month.

An updated trial report of the Pfizer vaccine says that “ Pfizer vaccine efficacy decreased from 96% to about 84% over 4 months.

The results of this study certainly indicates that booster vaccines are needed for the winter months to prevent another wave of deaths.

References

BMJ News. Covid-19: Pfizer vaccine’s efficacy declined from 96% to 84% four months after second dose, company reports
BMJ 2021; 374 doi: https://doi.org/10.1136/bmj.n1920 (Published 30 July 2021)Cite this as: BMJ 2021;374:n1920

BMJ News. Covid-19: Millions could be offered booster vaccinations from September
BMJ 2021; 374 doi: https://doi.org/10.1136/bmj.n1686 (Published 02 July 2021)
Cite this as: BMJ 2021;374:n1686

Thomas SJ, Moreira ED Jr., Kitchin N, et al. Six month safety and efficacy of the BNT162b2 mRNA covid-19 vaccine.medRxiv2021 [Preprint].

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 represent the author’s personal views held at the time of drafting the blog and may change overtime, particularly when new evidence comes to light. The blog is NOT previewed, commissioned or otherwise endorsed by any organisation that the author is associated with. The views expressed in this blog are NOT, in way whatsoever, intended to be a substitute for professional advice.

U.K. approach to vaccination proven to be the right one. Is it Luck or Foresight?

UK government wanted as many people have “some” degree of protection against the COVID-19 rather a only few people having “full” protection against COVID-19.

A recent paper published in BMJ validates the U.K. approach even though it was initially criticised by WHO ( world health organisation)..

Is it Luck or Foresight that U.K. Govt got it right? Probably both but more foresight than luck. Perhaps a cappuccino cup of foresight sprinkled with chocolate of luck.

Guardian. No data to support UK delay of vaccines’ second dose, says WHO.
Sarah Boseley Health editor
Tue 5 Jan 2021 19.48 GMT

Daily Mail. UK should feel ‘vindicated’ over its ‘brave’ decision to delay second doses of Covid vaccines, World Health Organization official says. By Sam Blanchard Deputy Health Editor For Mailonline. 13:29, 08 Feb 2021 , updated 15:03, 08 Feb 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 the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you. The views expressed in this blog represent the author’s views held at the time of drafting the blog and may change overtime, particularly when new evidence comes to light. The blog is not previewed, commissioned or otherwise endorsed by any organisation the author is associated with. The views expressed in this blog are not in way intended to be a substitute for professional advice.

How effective are the COVID vaccines against the new Indian variant?

Everyone in U.K. hoped that we have turned the corner with this pandemic after the recent spike in infection from the Kent Variant,

But now comes the Variant from India. (the scientific name is B1.617.2 variant of concern).

The Indian variant appears to be more transmissible but no evidence yet that the Indian variant is inherently more deadly than the Kent variant.

Naturally, we are in a better place now than last year because of the vaccination.

But there is some evidence that spontaneous changes (mutations) in the B.1.617.2 variant virus may make it partially resistant to antibodies produced by vaccines.

So how effective are the current vaccines against this Variant from India?

Lab testing shows that the current vaccines can be still effective against the Indian variant but may not be highly effective as it is against the Kent/U.K. variant.

PHE data shows that after two doses, Pfizer vaccine is 88% effective against Indian variant compared to 93% effectiveness against the Kent strain.

After two doses, AstraZeneca jab is 60% effective against Indian variant compared to 66% effectiveness against the Kent variant.

But after the first dose, both vaccines were only 33% effective against Indian variant compared to around 50% efficacy against the Kent strain.

The vaccine protection is better with two doses of vaccine and that’s why the Govt is speeding up second vaccine dose in affected areas.

Fingers crossed, hope this strategy works !

References

BMJ. Covid-19: Caution urged while lockdown eases in England because of vaccine success
BMJ 2021; 373 doi: https://doi.org/10.1136/bmj.n1203 (Published 11 May 2021)
Cite this as: BMJ 2021;373:n1203

BMJ News Covid-19: UK cases of variant from India rise by 160% in a week
BMJ 2021; 373 doi: https://doi.org/10.1136/bmj.n1315 (Published 21 May 2021)
Cite this as: BMJ 2021;373:n1315

U.K. Govt. Most vulnerable offered second dose of COVID-19 vaccine earlier to help protect against variants. From: Department of Health and Social Care. Published 14 May 2021

Telegraph: Two doses of AstraZeneca vaccine provide over 80 per cent protection against Indian variant, PHE study finds.

Guardian. India Covid variant: is it a threat to the UK’s reopening plans?
Ian Sample Science editor
@iansample
Fri 14 May 2021 11.19 BST

Daily Mail. UK is in a ‘very good position’ against Covid variants as Pfizer says there is NO proof current jab needs updating to fight mutant strains. By Luke Andrews Health Reporter For Mailonline
16:30, 10 May 2021 , updated 18:12, 10 May 2021

Daily Mail. How deadly is India’s Covid variant and is it REALLY behind explosion of cases? Scientists say ‘perfect storm’ fuelled nation’s crisis and mutant strain just had a ‘head-start’ – as study shows vaccines DO work against it. By Connor Boyd Assistant Health Editor For Mailonline
16:26, 27 Apr 2021 , updated 08:17, 28 Apr 2021

Collier, DA et al. SARS-CoV-2 B.1.1.7 sensitivity to mRNA vaccine-elicited antibodies. Nature; 11 March 2021; DOI: 10.1038/s41586-021-03412-7

BBC. What is the India Covid variant and will vaccines work?
Soutik Biswas
India correspondent

BBC. Covid: Increasing confidence jabs work against Indian variant
By Doug Faulkner
BBC News

ONS. Coronavirus (COVID-19) Infection Survey, UK: 21 May 2021 (“early signs of a potential increase in the week ending 15 May 2021”)

BBC. Covid: Pfizer and AstraZeneca jabs effective against Indian variant – study
By Dulcie Lee
BBC News

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 represent the author’s views held at the time of drafting the blog and may change overtime, particularly when new evidence comes to light. The blog is not previewed, commissioned or otherwise endorsed by any organisation that the author is associated with. The views expressed in this blog are not, in way whatsoever, intended to be a substitute for professional advice.

How effective is a single dose of Pfizer and AstraZeneca vaccine?

UK government wanted as many people have “some” degree of protection against the COVID-19 rather a only few people having “full” protection against COVID-19.

So the U.K. government delayed the second dose of Covid vaccine for 12 weeks.

Some people have now been offered two vaccines but still there are many people who were yet to have the second dose. They would be wondering how effective a single dose of the vaccine is. How much protection they have now.

A recent paper published in BMJ provides very encouraging news .

With Pfizer vaccine, vaccine effectiveness reached 61% after 4 to 5 weeks of the first dose.

With AstraZeneca vaccine, vaccine effectiveness reached 73% after 5 weeks of first dose.

This data is very reassuring

But the data also stresses the importance of having the second dose for further protection.

Please do make a note that (a) vaccines do take a few weeks to be become effective after the first dose (b) no vaccine is 100% effective and (c) we also do not know how long this protection from vaccine will last.

BMJ. Effectiveness of the Pfizer-BioNTech and Oxford-AstraZeneca vaccines on covid-19 related symptoms, hospital admissions, and mortality in older adults in England: test negative case-control study
BMJ 2021; 373 doi: https://doi.org/10.1136/bmj.n1088 (Published 13 May 2021)
Cite this as: BMJ 2021;373:n1088

BMJ. Public health impact of delaying second dose of BNT162b2 or mRNA-1273 covid-19 vaccine: simulation agent based modeling study
BMJ 2021; 373 doi: https://doi.org/10.1136/bmj.n1087 (Published 12 May 2021)
Cite this as: BMJ 2021;373:n1087

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 represent the author’s views held at the time of drafting the blog and may change overtime, particularly when new evidence comes to light. The blog is not previewed, commissioned or otherwise endorsed by any organisation the author is associated with. The views expressed in this blog are not in way intended to be a substitute for professional advice.

Are COVID-19 vaccines safe in Children ?

Yes, Israel has vaccinated vulnerable children and there have been NO reports of unusual or unexpected reactions.

Pfizer has just released positive results of a study which looked at safety and efficacy of the Vaccine in 12 to 15 year olds.

Pfizer-BioNTech covid-19 vaccine has shown 100% efficacy against SARS-CoV-2 in 12 to 15 year olds.

The Vaccine reassuringly was well tolerated, and the side effects were no different from those observed in the group aged 16 to 25.

What about much more younger children?

A vaccine trial in the children aged 6 months to 11 years has been started recently and results should be available later this year.

References

SKY news. Wednesday 31 March 2021 14:35, UK

The Guardian. Wed 31 Mar 2021 14.20 BST

BMJ News. Covid-19: Pfizer reports 100% vaccine efficacy in children aged 12 to 15
BMJ 2021; 373 doi: https://doi.org/10.1136/bmj.n881 (Published 01 April 2021)
Cite this as: BMJ 2021;373:n881

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 the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you. The views expressed in this blog represent the author’s views held at the time of drafting the blog and may change overtime, particularly when new evidence comes to light. The blog is not previewed, commissioned or otherwise endorsed by any organisation the author is associated with. The authors views are not in way intended to be a substitute for professional advice.

Two New Vaccines against COVID-19

More good news on the vaccine front in the fight against the coronavirus.

Two new vaccines have reported positive results.

The NOVAVAX vaccine is first Vaccine to report efficacy against the new variants. It is 95.6% effective against the original strain of coronavirus.

NOVAVAX is 86% effective at protecting against the new UK variant, which is very reassuring. But the Vaccine is only, 60% effective against South African variant of the virus. The efficacy against Brazilian variant is unknown.

The Janssen vaccine, produced by the US giant Johnson & Johnson, is a single-dose vaccine and has proved 66% effective against Covid-19. The vaccine was just 57% effective in the South African part of the trial.

The reduction in efficacy of both vaccines against new variants is a bit worrying and indicates that if further new variants emerge in future, existing vaccines could be less effective and vaccines would need to be updated.

The Janssen vaccine uses a common cold virus and uses a approach similar to the Oxford Astra Zeneca Vaccine.

Novavax vaccine differs from existing vaccines and it uses a artificially produced COVID-19 spike protein, which is then assembled into nanoparticles to make them look like coronavirus.

Bloomberg: Covid Mutations Undercut Optimism Even as More Vaccines Near
By Robert Langreth
30 January 2021, 00:04 GMT
Updated on 30 January 2021, 12:02 GMT

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 the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you.

The views expressed in this blog represent the author’s views held at the time of drafting the blog and may change overtime, particularly when new evidence comes to light. The blog is not previewed, commissioned or otherwise endorsed by any organisation the author is associated with. The authors views are not in way intended to be a substitute for professional advice.

Can you get Coronavirus infection even after getting the Vaccine ?

Yes, you can get the COVID-19 infection even after the vaccines.

This is because no vaccine is 100% effective. ( Eg Pfizer 95%, Oxford 70%)

The distressing story of a Nurse in Wales getting the infection after vaccination is an example.

There is also a theoretical chance that protective effect of vaccine is affected by new variants of Coronavirus.

But it is reassuring to learn that the Pfizer vaccine could be effective against UK and South Africa coronavirus strains (but the study is unpublished study and yet to be not peer reviewed ).

Be safe. Be aware !

References: BBC news. Covid: Nurse ‘angry’ over positive test despite vaccination. By Rachael Garside. BBC Wales News.

Covid-19: Pfizer/BioNTech vaccine judged safe for use in UK. By Michelle Roberts. Health editor, BBC News online. Published2 December 2020

Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. List of authors.
Fernando P. Polack, M.D., Stephen J. Thomas, M.D., Nicholas Kitchin, M.D., Judith Absalon, M.D., et al., for the C4591001 Clinical Trial Group*
December 31, 2020
N Engl J Med 2020; 383:2603-2615
DOI: 10.1056/NEJMoa2034577

Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK. Merryn Voysey, DPhil *Sue Ann Costa Clemens, PhD *Shabir A Madhi, PhD *Lily Y Weckx, PhD *Pedro M Folegatti, MD *Parvinder K Aley, PhD
et al.
Published:December 08, 2020DOI:https://doi.org/10.1016/S0140-6736(20)32661-1

CNN. Genetics experts worry coronavirus vaccines might not work quite as well against UK variant. By Elizabeth Cohen, CNN Senior Medical Correspondent. Updated 0328 GMT (1128 HKT) December 24, 2020

Telegraph: Coronavirus latest news: Pfizer vaccine could be effective against UK and South Africa strains, study says. Gareth Davies, breaking news editor. 8 JANUARY 2021 • 9:41AM (“Pfizer Inc and BioNTech’s Covid-19 vaccine appeared to work against a key mutation in the highly transmissible new variants of the coronavirus discovered in the UK and South Africa, according to a laboratory study conducted by the US drugmaker. The not-yet peer reviewed study by Pfizer and scientists from the University of Texas Medical Branch indicated the vaccine was effective in neutralizing virus with the so-called N501Y mutation of the spike protein.”)

Disclaimer: Please note- This blog is NOT medical advice. This blog is purely for information only and do check the the sources where cited. Please DO consult your own doctor to discuss concerns and options relevant to you.

The views expressed in this blog represent the author’s views held at the time of drafting the blog and may change overtime, particularly when new evidence comes to light. The blog is not necessarily endorsed by any organisation the author is associated with and the authors views are not in way intended to be a substitute for professional advice.