THE killer MRSA superbug is being spread through Merseyside hospitals because of chronic overcrowding on wards, it was claimed yesterday.

Five local hospital trusts have reported breaching a Department of Health (DoH) guideline that no more than 85% of beds should be occupied at any one time.

The independent Health Protection Agency (HPA) has warned it is difficult to isolate infected patients if the "bed occupancy rate" rises above 85%.

But the rate reached an average of 92.2% at Aintree Hospitals trust in the last financial year, according to figures from the Liberal Democrats.

Royal Liverpool and Broadgreen (89.2%), St Helens and Knowsley (88.8%), Southport and Ormskirk (88.5%) and the Walton Centre for Neurology (87.7%), also exceeded the guideline.

In Cheshire, the Countess of Chester (88.2%) topped 85%, while North Cheshire Hospitals reported an occupancy rate exactly the same as the recommended maximum.

The latest MRSA figures revealed that Aintree Hospitals and the Royal Liverpool and Broadgreen had the highest infection rates in Merseyside.

But, while the number of cases leapt from 48 in the previous year to 70 at Aintree, the total fell at the Royal Liverpool and Broadgreen, from 88 to 77.

Steve Webb, the Lib-Dem health spokesman, blamed the Government for the overcrowding, accusing ministers of attempting to cut waiting lists at all costs.

He added: "In some hospitals, a bed hardly has time to get cold before the next person occupies it, making effective infection control all the more difficult."

But a spokesman for the Royal Liverpool and Broadgreen said it had little choice but to exceed the 85% guideline, because half of its admissions were emergencies.

He added: "Our bed occupancy rate is consistently running at a high level, because we are a very big and a very busy city centre hospital.

"But that doesn't have to mean more MRSA, because we have made a tremendous effort in bringing down the number of cases by 10% last year."

However, Sally Ferguson, Aintree's director of nursing, accepted the link was possible "since high occupancy reduces the opportunity to nurse infected patients in single rooms."

Up to 5,000 hospital deaths a year have been linked to the superbug, although criticism of the Government was eased by a 6% fall in the infection rate reported in June.

Other local hospitals were below the 85% figure, including Wirral Hospital (82.7%), the Royal Liverpool Children's (72.4%) and Liverpool Women's Hospital (63.2%).