Analysis shows dramatic fall in the number of people living with undiagnosed HIV in England

England is on track to have diagnosed 95% of people living with HIV by 2025, putting it in a strong position to eliminate HIV transmission by 2030, say researchers at the MRC Biostatistics Unit, University of Cambridge, and Public Health England (PHE).

In 2014, UNAIDS set an ambitious target of 90-90-90 by 2020 – that is, 90% of all people living with HIV will know their HIV status; 90% of all people with diagnosed HIV infection will receive sustained antiretroviral therapy; and 90% of all people receiving antiretroviral therapy will have viral suppression.

According to the Cambridge and PHE team, in 2019 there were an estimated 105,200 people living with HIV in the UK, of whom 94% were aware of their HIV status. In addition, 98% of those living with diagnosed HIV were on treatment, and 97% of these were virally suppressed. In other words, England had already reached the UNAIDS goals.

In a publication today in The Lancet Public Health, the researchers extended their analysis of evidence from multiple surveillance, demographic, and survey datasets relevant to HIV in England from estimating HIV prevalence in a single year to estimating the trends over time in HIV prevalence. Trends in the number of people living with HIV, the proportion of people unaware of their HIV infection, and the corresponding prevalence of undiagnosed HIV are reported.

According to their analysis, the estimated number of people in England living with HIV aged 15-74 years who were unaware of their infection halved from 11,600 in 2013 to 5,900 in 2019, with a corresponding fall in prevalence from 0.29 to 0.14 per 1,000 people.

At the same time, the increase in the number of people living with diagnosed HIV resulted in the total number of people living with HIV rising from 83,500 to 92,800 over the same period. The percentage of people living with HIV whose infection was diagnosed therefore steadily increased from 86% in 2013 to 94% in 2019, reaching the UNAIDS target in 2016 – and even earlier, in 2013, for Black African heterosexuals.

Professor Daniela De Angelis from the MRC Biostatistics Unit, the study's senior author, said: "Overall, we see a positive picture for the HIV epidemic in England, with a dramatic fall in the number of people living with undiagnosed HIV. We estimate we are already several years ahead of the UNAIDS 2020 goals and are on target to reach 95% diagnosed by 2025 and to eliminate HIV infections by 2030.

Dr Anne Presanis from the MRC Biostatistics Unit added: "However, examined more closely, the situation is not as positive for everyone. We estimate that areas of England outside London have not seen as steep a decrease in undiagnosed HIV prevalence as in London, and there is evidence of missed opportunities to diagnose HIV infections among some population subgroups."

In England, gay, bisexual, and other men who have sex with men, and Black African heterosexuals remain disproportionately affected by HIV, with considerably higher undiagnosed HIV prevalence per population in 2019 than heterosexuals in other ethnic groups. However, undiagnosed HIV prevalence rates within these communities have seen dramatic falls: for gay, bisexual, and other men who have sex with men, prevalence fell from 13.9 to 5.4 per 1,000, and for Black African heterosexuals prevalence fell from 3.3 to 1.7 per 1,000 population.

London saw more dramatic falls in the prevalence of undiagnosed HIV during the study period than other regions of England, down from 0.74 to 0.31 per 1,000, compared to a decrease from 0.20 to 0.11 per 1,000 outside London.

Although sexual health clinics provide free and confidential HIV testing to all clinic attendees, the researchers estimated that among heterosexuals in an ethnic group other than Black African, undiagnosed prevalence in clinic attendees in 2019 was more than 30 times greater than in those who had not attended in the past year. This implies that sexual health clinics are missing opportunities for testing attendees. This is in line with findings from Public Health England that among individuals outside those subgroups at greatest risk of HIV infection, the proportion declining a HIV test had increased to more than one in four (27%) in 2016.

The researchers say their estimates have important implications for efforts to eliminate HIV transmission in England and the UK.

Dr Valerie Delpech, head of the HIV Team at Public Health England said: "This research is good news and shows that combination prevention, and in particular HIV testing and early treatment, is working in England. The increasing use of pre-exposure prophylaxis among persons at higher risk of HIV has further amplified our response to end HIV transmission. Nevertheless, further reducing the number of people who remain undiagnosed with HIV infection will become very challenging in the coming years. This is particularly the case for heterosexuals who may not consider themselves at risk of HIV.

"The priority must be to ensure that all sexual health clinic attendees are offered and encouraged to accept a HIV test, regardless of ethnicity, rather than the 73% that currently do test. If we can increase the number of clinic attendees unaware of their HIV status who get tested and diagnosed, as well as improve partner notification, the prospect of eliminating HIV transmission becomes increasingly likely."

The research was funded by the Medical Research Council and Public Health England.