By Adam Brimelow
BBC News, Health correspondent
Figures out today on MRSA and Clostridium difficile show there is a long way to go in the battle against hospital infections.
The unit looks like an air conditioner
And a report by the Healthcare Commission suggests that a lot of trusts have to do much more to adopt best practice.
This issue has been a key priority in the health service for several years. Scientists across the UK are looking at new ways of tackling the problem.
I went to Northwick Park hospital in north London to see how one idea has produced some promising results.
Northwick Park has the usual assortment of weapons in the battle to stem MRSA, C. difficile and the like, including alcohol gel rubs, hand washing sinks dotted around, and an overall emphasis on hygiene and cleanliness.
But now there is a new device being deployed in strategic spots across the hospital.
It looks like a small air conditioner unit, drawing in air and funnelling it past ultraviolet bulbs which kill bacteria that have been shaken around the room by the normal comings and goings of patients and staff.
Dr Peder Nielsen is the man in charge of infection control here.
He believes this ultra-violet air-cleansing unit opens up an important new front in the battle with MRSA.
He said: "We have never believed that airborne transmission had such an importance in this issue."
Dr Nielsen has been working on a study - as yet unpublished - looking at the impact of these units on environmental MRSA.
It compared two identical single-bed side rooms over three months - one with the UV cleaner, the other without.
The researchers regularly tested the rooms and the patients using them for MRSA.
During the trial nearly half these tests on patients in the "control room" were positive. None was in the room with the UV cleaner.
Dr Nielsen says the results were outstanding.
"The great idea here is that you have an instant isolation room whenever you need it.
"You just take it, you wheel it into the room where it is needed, and then you have an isolation room."
Some experts are sceptical about the idea. They are unconvinced about how readily MRSA can be passed on through the air.
The Department of Health has a rapid review panel which over the last three years has looked at getting on for 200 new products to tackle infections - including this one.
The department's chief microbiologist, Professor Brian Duerden, said it was important to keep an open mind.
"I hope we're not missing a trick but there's always more that we can do.
"And we can't ignore the fact that these organisms get out into the environment and can be transmitted to patients.
"So we do need to have surfaces that are readily cleaned, we have to have agents for use in the cleaning, we have to look at the air from the point of view of decontamination."
Northwick Park has bought 20 of the UV units - which cost £1,000 each.
The trust's chief executive Fiona Wise said she was ready to speak to colleagues across the health service about how well they've worked.
"Personally I think we need to do just a tiny bit more research and to continue to monitor the outcomes of it.
"But I do think what would be really important is to see if we can organise some other hospitals to see if the experience we had can be replicated, and that it is in fact this - in combination with other factors - which is really going to help us drive down infection levels."
Clearly it is very early days with this device.
But Dr Nielsen is excited about its potential - not just in helping to tackle MRSA, but also other infections including C. difficile, drug-resistant TB and even pandemic flu.