The mother of one victim of Creutzfeldt-Jakob Disease received a letter from the Prime Minister stating there was no evidence that eating meat caused the illness in people.
Jean Wake, 38, from Washington, Tyne and Wear, died in November 1995, years after working as a meat-chopper in a pie factory.
Her mother, Nora Greenhalgh, 75, wrote to the Government demanding answers on the issue after her once fun-loving daughter died.
She received a letter from John Major saying there was no evidence eating meat caused the illness in people and the public was properly protected.
The Prime Minister wrote to Mrs Greenhalgh last October, with the words: "I should make it clear that humans DO NOT get mad cow disease."
Jean Wake died after a 10 year fight against CJD and her mother has been convinced ever since her daughter fell ill that there was a link between mad cow disease and humans.
Following yesterday's statements, Mrs Greenhalgh, of Lakeside Village, Sunderland said: "I didn't believe Mr Major then and I don't believe him now.
"I was always convinced that Jean's illness was caused by eating beef and had a lot to do with her time working in a factory putting the fillings into pies as a younger woman.
"The disease has robbed me of a daughter and a young lass of her mam, and still the Government pretended it wasn't happening.
"The truth is long overdue, I think the British public deserve that from their Government."Reuse content