The UK Health Security Agency (UKHSA) said the NHS England program had tested 1,981,590 people for HIV, 1,502,799 for hepatitis C, and 1,185,678 for hepatitis B in the first two years.
The program was rolled out in 34 emergency departments in areas with high rates of bloodborne virus infections.
Of those tested, 73% had not previously been tested for HIV, 80% for hepatitis C, and 76% for hepatitis B.
The UKHSA analysis found that 1,957 people were newly diagnosed with hepatitis B, 762 with hepatitis C, and 391 with HIV.
The highest number of new diagnoses was for hepatitis B, which the UKHSA said reflects a greater prevalence of undiagnosed hepatitis B compared with hepatitis C and HIV.
It said 65% of people newly diagnosed with hepatitis C had no record of common risk factors such as homelessness, a history of incarceration or injecting drugs, suggesting the program is diagnosing people who may not be identified as at risk and so may not seek or be offered a test in other settings.
Dr Sema Mandal, consultant epidemiologist, and deputy director at UKHSA, said, “The opt-out testing program in emergency departments is making a significant impact in diagnosing those living with HIV, hepatitis C, and hepatitis B. Our evaluation indicates that many people are unaware they have a bloodborne virus infection. This program is identifying infections in people who might not seek testing otherwise, enabling them to access treatment earlier.”