https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8492451/
Vaccine. 2021 Oct 29; 39(45): 6565–6569.
Published online 2021 Oct 6. doi: 10.1016/j.vaccine.2021.09.065
PMCID: PMC8492451
PMID: 34625289
All vials are not the same: Potential role of vaccine quality in vaccine adverse reactions
Yihua Bruce Yu,⁎ Marc B. Taraban, and Katharine T. Briggs
OK, here's the first 3 paragraphs from that link (Fair Use):
A recent commentary in this journal proposes looking beyond polyethylene glycols (PEG) when investigating anaphylactic reactions to mRNA COVID-19 vaccines [1]. It suggests examining other ingredients in those vaccines as potential causes of anaphylaxis. We agree with the need to broaden the scope when investigating vaccine adverse reactions, but we propose going beyond vaccine ingredients. A recent study reported that 581 people with anaphylaxis histories from previous vaccine shots did not develop anaphylaxis after receiving the Pfizer/BioNTech mRNA COVID-19 vaccine [2], suggesting that the vaccine ingredients might not always be the cause for anaphylaxis associated with this vaccine. While both active and inactive ingredients of a vaccine may be the cause of some adverse reactions, another possible cause to consider is subpar quality of the individual vial.
We suggest taking the quality of individual vaccine vials into account in an adverse reaction investigation, i.e., a serious adverse reaction, anaphylaxis or other types, might be caused by one defective vial out of many good-quality vials. An argument for this possibility is that vaccine adverse reactions are not always reproducible on re-exposure [3], which hints at an element of chance. For example, a recent retrospective study found that 159 patients who had immediate reactions to the first dose of mRNA COVID-19 vaccines, including 19 individuals with anaphylaxis after the first-dose, tolerated the second dose [4]. The reason for this is unclear at this time. It is not inconceivable that the first and second doses may respectively involve vials of different quality, and therefore elicit different responses from a person. When the defect rate is low, it is highly unlikely that a given person will receive two bad doses in a row. For example, if the defect rate is 1 per 105, the probability that a given person receiving two bad doses is 10-10.
Indeed, focusing entirely on vaccine ingredients in adverse reaction investigations may leave an investigation unsolved when good-quality ingredients are not the cause. In Sweden, high counts of narcolepsy were noticed after immunization with Pandemrix (an H1N1 influenza vaccine) in 2009 [5]. Investigations that focused on the adjuvant in Pandemrix failed to establish a causal link between narcolepsy and the adjuvant [6]. To this date, the cause has not been identified [7]. The culprit might have been a few defective vials in the batch delivered exclusively to Sweden rather than the adjuvant or other ingredients. Collecting quality data on every vial before injection might have prevented those narcolepsy incidents, but such a practice is not currently in place. In fact, the current quality control system for vaccines is not well equipped to catch a few defective vials among many good-quality ones unless the defects are visible to human eyes.
1. It is speaking of variations in vaccine quality due to differences (probably source- or batch-related) in non-active ingredients (e.g. preservatives), not variations in the active ingredient.
2. The variations are incidental, unplanned. The OP article insinuates that Pfizer knowingly and intentionally gave employees something different from general-population recipients. This NIH in no way supports the OP claim.
3. The NIH article clearly is speaking of vaccines generally, not specifically and only Pfizer's Covid vaccine. For example these sentences from the quote above:
In Sweden, high counts of narcolepsy were noticed after immunization with Pandemrix (an H1N1 influenza vaccine) in 2009 [5]. Investigations that focused on the adjuvant in Pandemrix failed to establish a causal link between narcolepsy and the adjuvant [6]. To this date, the cause has not been identified [7]. The culprit might have been a few defective vials in the batch delivered exclusively to Sweden rather than the adjuvant or other ingredients.
My emphasis. The NIH article here references a different vaccine
(for H1N1 influenza), from GlaxoSmithKline
(not Pfizer), that does not use mRNA vaccine technology
(approved for use in Europe in 2009, over 11 years before the first mRNA vaccine was authorized for use), that is used with an adjuvant
(adjuvants are not used in mRNA vaccines).
That NIH article is not evidence that supports the OP claim.