There are loads of resources for this unit. YouTube has a range of clips on infections and ways to prevent infection. Attached are a few I have found useful. Highfield have a Level 2 booklet which is a good starting point especially for technical terms. A book I have just discovered is Infection control in clinical practice by Jennie Wilson, Pub Balliere Tindall Elsevier (ISBN 13: 978 0 70 20 2761 1). It provides excellent background reading for teacher and would be accessible to higher ability learners.
My students loved this unit and they really flourished on the independent learning/reserach front. The scribble pads allowed them make notes and then use the notes in a structured way to write reports. A great unit - to be recommended!