Introduction Guidelines recommend epidemiological treatment of patients presenting as a contact of infection. This potentially reduces the prevalence of infection, reducing infectivity and reduces patient visits. Over prescription of antibiotics poses a threat of future resistance development and exposes the patient to unnecessary treatment. An audit was carried out to determine if any themes could be identified to indicate a likely positive result in contacts.

Methods We audited asymptomatic contacts of chlamydia and gonorrhoea (PNC/PNG) attending GU services at BartsHealth (February 2016 for 3 months). Data on gender, sexual orientation, contacts (regular or casual), infection site, time since sex with contact, HIV status, STI in previous year were collected. Testing by Aptima NAATS for chlamydia/gonorrhoea and gonorrhoea culture.

Results Chlamydia 75 asymptomatic contacts (55 male/20 female). All treated as contacts. 25 had a positive result (34%). No factors could be associated with predicting a positive result, except a suggestion that a regular partner v casual partner. Gonorrhoea: 85 asymptomatic contacts (76 male/9 female). All treated as contacts. 27 had a positive result (32%). Being male >24years old/MSM/>5 partners (in 3m) and contact being a regular partner were suggestive of predicting a positive result.

Discussion The audit reinforces epidemiological treatment. Drawbacks of not treating include failure to return, onward STI transmission and inconvenience of re-attending. However, over 60% had potentially unnecessary treatment and with rapid turnaround of results (<2d), future universal treatment may need to be revised.