Emergency Department Opt-Out Testing Program Identifies Undiagnosed HIV

Undiagnosed HIV continues to drive avoidable morbidity and transmission, with many people identified only after substantial immune damage has occurred. In England, about one in 20 people living with HIV are unaware of their status, underscoring persistent gaps in routine screening pathways. New findings now demonstrate how a large-scale emergency department opt-out testing initiative is detecting infections earlier and linking patients to care.

The UK National Health Service (NHS) Blood Borne Virus Opt-Out Testing Program is a first-of-its-kind large-scale initiative operating in hospital emergency departments (EDs). Adults attending EDs in 88 towns and cities with high HIV prevalence who are already having blood drawn are routinely tested for HIV, hepatitis B, and hepatitis C unless they opt out. Individuals with positive results are then offered specialist support and a treatment plan.

Image: According to the latest NHS data, the emergency department opt-out testing initiative has identified 1,900 previously undiagnosed HIV cases since launching in April 2022 (Image Credit: Adobe Stock)

According to the latest NHS data, the program has identified 1,900 previously undiagnosed HIV cases since it launched in April 2022. An economic evaluation published in The Lancet HIV and led by the University of Bristol and the National Institute for Health and Care Research (NIHR) estimated that 802 diagnoses from the program’s initial phase could avert about 187 HIV-related deaths and 28 new infections over 20 years.

Research by the UK Health Security Agency (UKHSA) found that 93% of newly diagnosed individuals reached by the initiative had no record of a prior HIV test, indicating that the model is engaging people unlikely to be tested through other pathways.

The study concluded the approach offers good value for the NHS, citing a low per-test cost and the clinical benefits of earlier diagnosis and treatment initiation. The program forms part of national efforts to reduce HIV transmission, with NHS leaders continuing the rollout and three additional hospitals expected to begin ED testing by April 2027. The government’s HIV Action Plan 2025–2030 also sets out continued investment to sustain opt-out testing for HIV, hepatitis B, and hepatitis C in high-prevalence areas.

“At around £6 per HIV test, the program is good value for money for the NHS, and importantly has led to linkage to treatment to improve the health and lifespan of many people who were previously living with undiagnosed HIV,” said Dr. Josephine Walker, lead author at the University of Bristol and NIHR Health Protection Research Unit in Evaluation and Behavioural Science.

“Knowing your HIV status is as important as checking your blood pressure, and our pioneering NHS Blood Borne Virus Opt-Out Testing Program is helping hundreds of people get a diagnosis—often before they have any symptoms at all—which means they have access to life-saving treatment," said Professor Francesca Swords, national medical director for the NHS.

"NHS staff are committed to improving early detection of HIV and other blood-borne viruses, and improving awareness of these health conditions to reduce the chance of people unknowingly passing it on to others. The successful rollout of this initiative in hospital EDs is an excellent example of how the NHS is working to make every contact with patients matter by supporting people to stay well, access treatment, save lives and make the best use of its resources,” added Prof. Swords.

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