Patient groups that have been identified as being at greater than normal risk of developing transmissible spongiform encephalopathies (TSE) include:

1. patients with a family history of CJD or other prion disease
2. recipients of pituitary derived hormones such as human growth hormone or gonadotrophins
3. patients who have had surgery on the brain or spinal cord
4. patients who have received more than 50 units of blood or have received blood or blood components on more than 20 occasions, since 1980.

Before carrying out any procedure that might involve the re-use of a contact lens or ophthalmic device you should, as far as possible, question the patient to establish if they fall into any of the above high-risk groups. If the patient is in a high-risk group, you must only use items intended for single patient use. If this is not possible you should consider referring the patient to the Hospital Eye Service.

If you use a re-usable item in an emergency with a patient in one of the above high-risk groups, you should discard it immediately after use.

If you examine a patient with a known transmissible infection, you should:

1. cover cuts and abrasions to skin with waterproof dressings (preferably coloured) 
2. carry out hand hygiene before and after each patient contact and before and after leaving their home or care home, see section; Methods of preventing infection transmission from person to person, and
3. follow the guidance in section; Situations of increased concern – transmission from person to person.