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.
(post is archived)