Archive for April 14th, 2021

J&J vaccine halted … so what?

April 14, 2021

Here’s what you need to know.

The J&J vaccine a “viral vector DNA” vaccine that is very different than the Pfizer and Moderna “messenger RNA vaccines” … and their long-term effects may be different.

Below is a very detailed analysis of the differences and their implications.

The J&J blood-clotting issue is a near-immediate injection side-effect that is very rare … less than a 1 in million occurrence … less likely than getting struck by lightning.

Statistically-speaking, the blood-clotting occurrence rate is so low that it raises questions as to why the vaccine has been halted.

Up until yesterday, most “experts” were saying “Take whichever vaccine is available to you first.”

Yesterday, Dr. Fauci and the other political-scientists were lock-stepping an “abundance of caution” message.  It will be interesting to see how this situation evolves, especially since…

For the record: Pfizer and Moderna vaccines were approved by the Trump administration; J&J was developed under the auspices of Trump’s Operation Warp Speed, but the J&J vaccine was approved by the Biden administration.

MUST READ: Here is a detailed recap of how the vaccines work and how they compare.  It’s long, but well worth the reading time.

The topline:

The 3 currently relevant brands (Pfizer, Moderna, J&J) are “well tolerated” (i.e. they exhibit few or no side effects) and provide high levels of protection …  with near total protection against hospitalization or death.

In clinal trials, Pfizer & Moderna scored higher in overall protection (roughly 95% against symptomatic infections) than the J&J vaccine (72%) in the U.S.

Most experts consider the difference in effectiveness rates to be more a function of when and where the clinical trials were done than the relative effectiveness of the vaccines.

Specifically, the J&J trial was done in a more “hostile” Covid environment: a higher prevalence of Covid and emergence of new Covid strains (especially the South African variant).


Regarding the variants…

“Laboratory studies and clinical-trial data suggest that all of the Covid  vaccines will provide significant protection (i.e. greater than 50% effectiveness) against emerging strains of the Covid virus.”  Source

It’s highly likely that an additional shot — either a booster or a reformulation — will eventually be required for all brands and types of vaccines to combat the variant strains.


It’s uncertain how effective the vaccines are preventing asymptomatic infections or how long the vaccines provide immunity against serious symptoms.

But, the consensus seems to be that there is very high protection against asymptomatic infections … and that the immunities last for at least several months, maybe longer.

That said, annual shots seem to be likely.

Again, the most compelling immediate effectiveness result to consider: all brands claim near total protection against hospitalization and death with unlikely side effects.

My take: Call it a push on effectiveness.


The J&J vaccine is easier to distribute since it requires less demanding refrigeration.

So, once production is ramped up, it will probably be more ubiquitous in rural areas and in low volume vaccination outlets (e.g. doctor’s offices, urgent care clinics and smaller pharmacies).

As well publicized, Pfizer & Moderna are currently administered in 2 doses with the 2nd dose following 3 or 4 weeks after the 1st.

The J&J vaccine only requires a single dose, making it a good fit for, say, high volume mass vaccination sites and for people who want the convenience of one & done (e.g. workers who are schedule constrained or people with limited access to distribution sites).

The Pfizer & Moderna vaccines are likely to be concentrated in, say, public health department vaccination clinics, targeted to high vulnerability populations.


That’s probably all that you really need to know, but if you’re interested in the comparative science of the vaccines, keep reading…


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