Ordinarily a "data dump" means downloading a large batch of data so one can comb through it and examine the contents for meaningful analysis.
But when it comes to vaccine related study data the term takes on a new and different meaning. It is now alleged (by Dr. William Thompson, aka the "CDC Whistleblower") that he and his colleagues met to destroy (dump in a garbage can) documents linking an increased risk of autism with receipt of an MMR vaccine prior to 36 months (particularly in black males).
In his statement Dr. Thompson refers to the Verstraten study - a study often cited as "proof" that there is no association between the preservative thimerosal (a form of mercury) and autism - and he refers to it as a "debacle"! Here is one analysis as to why this "study" is rightly called a debacle.
While Dr. Thompson kept silent until 2014 he at least had enough sense of personal ethics not to destroy his own copies - he didn't dump his data. He also finally responded to the nagging of his conscience about this matter.
As Congressman Posey has stated, a thorough investigation and congressional hearings are called for.
What's also called for is a return to greater freedom in medical decision-making ... those who want vaccines should get them, those who decline should not face an retaliation for this decision. Vaccination should not be linked to school participation, employment, nor anything else.