Covid: Why You Need a Booster

Let’s take a quick look at the preliminary evidence regarding the lack of effectiveness of vaccination without a booster shot.

THE BAD NEWS? ALL THREE of the COVID-19 vaccines approved in the United States seem to be significantly less protective against the new Omicron variant of the coronavirus, at least in laboratory testing.

Fortunately, a booster dose appears likely to restore most of the protection. These are the conclusions of a recent study from researchers at Massachusetts General Hospital (MGH), Harvard, and the Massachusetts Institute of Technology (MIT).

Omicron aggressively spreading

Explosive. That’s the word I would use to describe the growth and spread of the Omicron coronavirus variant. The virus has been discovered in 89 countries and has a doubling rate of 1.5 to 3 days in regions with community transmission. These are observations from the World Health Organization (WHO) today.

Is the rapid growth secondary to the variant virus’ ability to evade our immune systems, or is it secondary to increased transmissibility for other reasons? We don’t know.

Let’s take a quick look at the preliminary evidence regarding the lack of effectiveness of vaccination without a booster shot. The Boston region researchers tested blood from people who had received the Moderna, Pfizer/BioNTech, or Johnson & Johnson vaccines against a pseudovirus engineered to look like the Omicron variant.

There appeared to be very little (if any) neutralization of antibodies of the variant from any of the vaccines. However, the blood from those who recently had a booster shot neutralized the variant.

Photo by Jeremy Bezanger on Unsplash

These research observations are in line with some other recent reports. In a study announced earlier this week, Oxford University (England) researchers tested subjects’ blood samples 28 days after their second dose of the Oxford-AstraZeneca or Pfizer-BioNTech vaccine.

When the scientists introduced Omicron to the samples, there appeared to be a substantial fall in the neutralizing antibodies that fight Covid. Some recipients failed to neutralize the virus at all. This response appears inferior to that seen against earlier variants of the coronavirus. Here is the take of the study’s authors:

“This will likely lead to increased breakthrough infections in previously infected or double vaccinated individuals, which could drive a further wave of infection, although there is currently no evidence of increased potential to cause severe disease, hospitalization or death.”

The researchers reported this pre-print study, which is yet to be peer-reviewed, on the MedRxiv server.

Good news

BioNTech and Pfizer said last week that a three-shot course of their COVID-19 vaccine neutralized the new Omicron variant in a laboratory test. However, the two doses resulted in significantly lower neutralizing antibodies.

Moderna and Johnson & Johnson have not released their data about the vaccines against the new variant.

I am glad that I got a booster vaccine shot. Thank you for joining me today.


Medika Life has provided this material for your information. It is not intended to substitute for the medical expertise and advice of your health care provider(s). We encourage you to discuss any decisions about treatment or care with your health care provider. The mention of any product, service, or therapy is not an endorsement by Medika Life

Michael Hunter, MD
Michael Hunter, MD
I received an undergraduate degree from Harvard, a medical degree from Yale, and trained in radiation oncology at the University of Pennsylvania. I practice radiation oncology in the Seattle area.
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