Between 3% and 5% of staff are thought to be "colonised" with the superbug methicillin-resistant Staphylococcus aureus.
A total of 1,330,544 people work for the NHS and the Government estimates the number of employees carrying the bug is up to 66,527.
According to the Office for National Statistics in 2007 1,593 people dead from MRSA.
In response to a written parliamentary question from East Yorkshire MP Greg Knight who asked Ms Keen what the "number of NHS clinical staff who are carriers of MRSA" is.
The minister replied "It is estimated that 3%-5% of staff are colonised with methicillin-resistant Staphylococcus aureus."
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