Unfortunately,  bugs such as VRE are present in hospitals, no matter how hard staff try, patients who have immune systems worn down by surgery / illness / increasing age / ill health / frailty / long hospital stay / .

will be likely to have infection at some stage.

The number of wounds and breaks in the skin eg drainage / urinary catheters / intubation - increase the risk.

Staff these days are well aware of infection, but where you have a large number of very sick, especially surgical patients,  'bugs' happen

There will always be and has always been 'bugs' who will take the opportunity to take advantage in a low immune system person.

I hope your wife improves and can be on her way home soon  - ask about  a place in a rehabilitation centre, when she is fit for discharge.

My late mum spent 3 weeks in one, after her major bowel op - was excellent and got her strong and confident enough to come home safely

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