This is an important aspect of looking after the patient and the community and is a similar approach as would be taken for contacts of patients with sexually transmitted infections. Certainly it can be difficult - especially if the contacts do not usually attend your practice. When we talk about contacts of hepatitis C, the individuals who are a priority for testing and treatment are people who inject drugs (PWID), part of the so-called 'injecting network'. They are at greater risk of getting hepatitis C from others, and - before treatment - at greater risk of passing it on to others. Treating HCV-positive patients and contacts helps to end transmission and protect others. Your patient may be currently injecting but equally may not have used drugs intravenously for months, years or even decades. For some patients it's not known how they got the infection or it's unrelated to injecting. But if your patient can identify contacts who are within their past or present 'injecting network', then these contacts should be invited and encouraged to have HCV testing and treatment if necessary.
If the contacts are not seen in your practice, or you are otherwise concerned about confidentiality and privacy, then use this letter. Just fill in your practice's details, then give it to your patient to give to their contacts, if they are comfortable to do so.