An increase in recently acquired HIV in PWID has been noted in Dublin since early 2015. We have defined recently acquired HIV infections as those in which the person tests positive using a combined HIV antigen/antibody screening assay, negative or indeterminate on a confirmatory immunoblot assay and is p24 antigen positive, or has had a HIV negative test within the 12 months prior to the positive test or who suffers an acute HIV sero-conversion illness.

A multidisciplinary incident team has been set up by the Director of Public Health in Dublin to investigate and respond to the increase. The team includes public health and HIV Physicians, GPs providing services for drug users and homeless populations, HSE social inclusion, addiction clinicians, clinical virologist and HPSC. An epidemiological investigation is underway. Clinicians from the drug services are concerned that the increase is linked to injection of a synthetic cathinone PVP, street name Snow Blow, with consequent more frequent injecting, and unsafe sexual and needle sharing practices. This has mainly been seen in chaotic drug users, who report polydrug use, and are often homeless.

Evidence to date indicates that the increase has been occurring since June 2014. Fifteen cases of recently acquired HIV infection (confirmed cases) and one case with epidemiological link to a recently acquired HIV infection (probable case) have been diagnosed in PWID in Dublin from June 2014 to June 2015. Of the 15 cases, seven are p24 antigen positive indicating very recent infection. A further 16 possible cases in PWID are currently under investigation and new cases continue to be detected. Amongst the 16 confirmed and probable cases, 11 are male and five are female, and the mean age is 35 years (range; 24 to 51 years). A case control study is underway to identify any association between use of Snow Blow leading to an increase in unsafe injecting practices, and at-risk sexual behaviour, and acquisition of HIV......