SIX cases of the superbug MRSA were discovered at St Helens and Whiston hospitals last year.
Official NHS figures also show one unconfirmed case is still being reviewed.
There were five cases of MRSA in 2011 and eight in 2010.
Despite health chiefs’ efforts, hospital-acquired MRSA has stubbornly resisted attempts to eradicate it.
The full breakdown of cases over recent years is:
* 2011 - five cases
n* 2010 - eight
n* 2009 - five
n* 2008 - three
Several years ago, bosses at Whiston Hospital proclaimed they enjoyed an MRSA-free year.
But their claims were later challenged when documentation emerged citing the superbug as a cause of death for a woman who died while being treated at Whiston Hospital.
Although no more aggressive than any other infections, it is more resistant to treatment.
A trust spokeswoman said health chiefs were working relentlessly to combat infects across both hospital sites.
She added: “Over half a million patients each year are treated at St Helens and Whiston hospitals. The Trust is never complacent and has a robust action plan in place to reduce and prevent infection.
“We remain committed to providing exceptionally high standards of care for our patients.”