Pfizer Vaccine Protection Wanes After 6 Months: Study

[Northerner]

Pfizer's COVID-19 vaccine continues to show strong protection against serious illness and hospitalization after 6 months, but overall protection against the virus appears to wane after a half a year, according to a new study.

The July 28 preprint report of the study, which has not been peer reviewed, suggests a gradual "declining trend in vaccine efficacy" over 6 months after a two-dose regimen of the Pfizer vaccine. The study included more than 45,000 people worldwide.

The study found that overall effectiveness fell from 96% to 84%.

A third booster dose of the Pfizer vaccine increases neutralizing antibody levels against the Delta variant by more than five times compared to levels after a second dose in people aged 18 to 55 years, new data from Pfizer show.

The immune response to the third dose appears even more robust ― more than 11 times higher than the response to second shot ― among people aged 65 to 85 years.

Pfizer Vaccine Protection Wanes After 6 Months: Study

Following reports that antibody levels can wane after a second dose of the Pfizer mRNA come more encouraging data regarding a third dose.

www.medscape.com

 

[Inka]

Thanks for that @Northerner 🙂 I had the Pfizer vaccine so interested to read this.

 

[Northerner]

Thanks for that @Northerner 🙂 I had the Pfizer vaccine so interested to read this.

Yes, me too 🙂

 

[mikeyB]

Interesting that you posted this report of reduced efficacy because of reducing antibodies. Long term immunity is mediated by T-cells, not by keep producing antibodies wastefully.

As I’ve said countless times, I’m immune to measles, but you won’t find any antibodies to measles in my bloodstream. They would only appear if I came into contact with some sprog who was infected.

Nobody yet knows how long T-cell mediated immunity to Covid-19 lasts.

 

[nonethewiser]

Roll on 3rd dose then.

 

[mikeyB]

I should add to my post above that Covid-19 is a coronavirus. Most coronaviruses cause a common cold, around 20% of them. If you live in the same area for around 3 years, you develop immunity to the geographically local viruses - they tend to stick around locally. Everyone knows someone who has said “I never get a cold”. They will be a local. When we moved to the Isle of Mull, we both were getting colds for most of the first winter, but after that were fine. That always happens if you move somewhere distant.

Now that is T-Cell mediated, so if we can do that with workaday coronaviruses - and Covid-19 is just another - then we’ll all be fine. An annual booster is a tad over the top, it could probably be biennial, but should easily do the trick.