HIV/AIDS was first diagnosed in 1981. As of year-end 2018, 160,493 people have been diagnosed with HIV in the United Kingdom and an estimated 7,500 people are living undiagnosed with HIV. New diagnoses are highest in gay/bisexual men, with an estimated 51% of new diagnosis reporting male same-sex sexual activity as the probable route of infection. Between 2009 and 2018 there was a 32% reduction in new HIV diagnosis, attributed by Public Health England (PHE) to better surveillance and education. PHE has described an "outbreak" in Glasgow amongst people who inject drugs, and has campaigns targeting men who have sex with men in London and other major cities. London was the first city in the world to reach the World Health Organization target for HIV, set at 90% of those with HIV diagnosed, 90