El Pais, a Spanish daily, reported that the infections were caused by Acinetobacter baumannii, a highly  virulent bacteria that has strains which are resistant to most of the drugs.

The report said that the situation was so bad at the hospital that the intensive care unit had to be destroyed, so that a new, non-contaminated structure could be built.

Hospital denial

Joaquin Martinez, the hospital's director, denied that all the 18 deaths were directly caused by the bacterial infection.

"Patients in a critical state die from their illness, accompanied exceptionally by an infection of multi-drug resistant Acinetobacter baumannii and other types of micro-organisms, because they are more vulnerable due to their existing health problems," he said.

El Pais quoted Juan Carlos Montejo, a doctor at the hospital, as saying that the bacterium "contributed to the death" of other patients, but it had not been the determining factor.

Acinetobacter baumannii tends to infect those in intensive care with fragile immune systems and can lead quickly to pneumonia.

It is  easily transmitted from hospital equipment or from patient to  patient.

Earlier in 2003, it led to the death of around 20 people in several hospitals in northern France.