Apparently not much... From the BBC News:
"Concerns are being raised about NHS performance on infection control in England - just weeks after ministers announced MRSA targets had been met.-----------------------------
The Healthcare Commission's annual report on NHS performance showed a quarter of trusts were struggling to meet the hygiene code.
The data also showed that just over half of hospitals had managed a sustained reduction in MRSA rates.
It comes after ministers claimed they were winning the superbug fight.
In September, Gordon Brown hailed the "tremendous achievement" in halving the national MRSA rate over the previous three years.
But the watchdog adopts a slightly different approach to measuring performance.
Instead of relying on national quarterly figures as the government does, the Healthcare Commission uses annual figures broken down on a trust-by-trust basis which officials said was a better demonstration of sustained improvement.
These showed that only 52% of trusts had reduced MRSA by 60% - the figure was set higher than the national target in talks with ministers to ensure it was met across the board."
The number manipulation is even worse in U.S. hospitals, BTW... Institutional fudging is endemic in most hospitals.