I came across an interesting by the scientist who discovered this.

He put his time an effort into making it easy for other labs to run the same test he did instead of submitting a paper for peer review because the peer review process is useless. It seems as though papers are peer reviewed entirely on opinion. No one reviews a paper by trying to reproduce the results.

Not knowing WTF a plasmid is, this helps a lot to understand the problem of contamination of a vaccine with these:

A plasmid is a small circular DNA molecule found in bacteria and some other microscopic organisms. Plasmids are physically separate from chromosomal DNA and replicate independently. They typically have a small number of genes — notably, some associated with antibiotic resistance — and can be passed from one cell to another. Scientists use recombinant DNA methods to splice genes that they want to study into a plasmid. When the plasmid copies itself, it also makes copies of the inserted gene.

Basically sounds like these things will copy on their own and inhabit cells, basically a third carrier of DNA alongside the normal chromosomes and mitochondria.

This note about Pfizer needs a better explanation.

In 1979, when cases of Sudden Infant Death related to the DTP Vaccine emerged in Tennessee, Wyeth (now Pfizer) decided to address the issue by limiting the distribution of affected lots to a single state, presumably in an effort to conceal any correlations.

They had a problem where occasionally a lot of vaccines would be manufactured poorly and result in multiple adverse effects and deaths. Rather than improve their quality control (which costs money) they spread out each lot of vaccines across multiple states so that a poorly manufactured lot would not kill enough people in any single state to be noticed. This made the deaths look more like isolated, random occurrences, rather than a clearly preventable problem.