Sir Elton John is heading to Parliament to urge ministers to do more to hit a 2030 target of eliminating new HIV cases in England, the OceanNewsUK has learned.
The rock legend will address MPs at a meeting on Wednesday evening.
It comes as more than 580 previously undiagnosed cases have been identified by a pioneering new testing scheme.
Under the scheme, anyone having a blood test in selected hospital A&E units has also been tested for HIV, Hepatitis B and Hepatitis C, unless they opted out.
According to NHS figures seen by the OceanNewsUK, the "opt-out testing" pilot project has identified more than 3,500 cases of the three bloodborne infections since April 2022, including more than 580 HIV cases.
The trials have been taking place in 33 hospitals in London, Greater Manchester, Sussex and Blackpool, where prevalence is classed by the NHS as "very high".
Sam, whose real name is not being used, lives in Greater Manchester and is in his 40s. Last year, he had a blood test after going to A&E following an accident.
"I got a phone call two days after being in A&E," he says, "just saying to me we've got some concerns about a blood test that was done at the time. They asked me to come in and do some further tests.
"I hadn't realised about the opt-out testing at the time, so I wasn't expecting a phone call from a health clinic. I thought it was about a survey or something about my experience in A&E."
After a two-week wait, Sam was diagnosed with HIV.
"It felt like this was happening to somebody else. I wasn't expecting it. My family don't know, and I don't want to cause them any distress.
"And I feel maybe their lack of knowledge about the HIV virus and the 80s and how things were then, it makes me a lot more reluctant to tell them."
The opt-out trials, which cost £20m, were designed to identify cases in people unlikely to get tested at a sexual health clinic and are based on similar bloodborne infection testing programmes already in place for pregnant women.
The NHS says 42% of HIV diagnoses in the UK are made late, when the immune system has already been significantly damaged.
NHS England, which has been leading the pilots, says opt-out testing is more likely to lead to an early diagnosis.
Sources in Westminster say they believe this will save the NHS money in the long term.
Sam now takes one tablet a day and goes for a check-up every six months.
"The rest of my life is completely as it was before," he says.
But that's not the case for everyone.
Jackie, who lives in the West Midlands where HIV prevalence is high but opt-out testing is not available, was given a late diagnosis.
"Nobody had got a clue what was wrong with me," she says.
"Losing my hair, losing weight, thrush in my mouth and I kept going back to the GP. And it wasn't until my breathing got so bad, which was a few years down the line, they put me in hospital."
Doctors still couldn't figure out what was making Jackie so ill. Then eventually, they decided to carry out an HIV test.
She believes there were opportunities much earlier on when she could have been given a test.
What is HIV?
HIV stands for Human Immunodeficiency Virus - which weakens the immune system
More than 94,000 people are living with HIV and accessing care in England
Very successful treatment means most people affected can live long, healthy lives
HIV medication reduces virus levels so much that passing on the virus to sexual partners is now only a tiny risk
HIV diagnoses went up from 3,118 in 2021 to 3,805 in 2022
Most of that rise is down to people previously diagnosed abroad being given a diagnosis and care on arrival in England.
Those diagnosed late tend to be women, who are less likely to take an HIV test
Overall, more and more people are accessing tests as well as pills to reduce chances of getting HIV through sex
Campaigners have been calling on the government to expand the testing to areas classed as having high prevalence, such as the West Midlands and Liverpool.
But neither the government nor Labour have yet committed to providing the extra funding for this expansion, which is estimated to be around £25m a year.
Conservative MP Steve Brine set the government's target of eliminating new HIV cases by 2030 when he was a health minister.
Mr Brine, who now chairs the health select committee, says that target will not be hit, unless opt-out testing is rolled out to more areas.
"Given that the number of transmissions of HIV in the straight community now outstrip the gay, lesbian, bisexual community, then you know, where is HIV? It is all around us," he said.
"We've got to do the opt-out testing in as many places as possible."
Sir Elton, whose Aids Foundation played a key role in pioneering opt-out testing, will be speaking at an event in Parliament later hosted by the all-party parliamentary group for HIV and Aids.
The event has been organised to mark World Aids Day and the end of Sir Elton's touring career, and he is expected to specifically mention opt-out testing.
It is understood that the government is pleased with the results of the opt-out pilots, but the initial cost of rolling it out to further areas means no decision has yet been confirmed.
Sam is supportive of further opt-out testing, but believes more could be done to make clear that people are being tested in the first place.
"I'm very happy that I went through it now," he says.
"At the time, I did feel a little bit ambushed. I felt that maybe some of my rights had been taken away from me. I thought that was my choice to make.
"However, it's obviously worked in my favour because I don't know for a fact I would have said yes or no to that test."
NHS national medical director, Prof Sir Stephen Powis, said opt-out testing had been a success, allowing earlier diagnosis and treatment, particularly for groups less likely to come forward for routine testing.
"We would like to extend this programme," he told OceanNewsUK's Today programme.
"We're working closely with colleagues at the Department of Health to work out how we can do that and which areas of the country we would go next and I am hopeful we will be able to make some announcements on this in the near future."
A spokesperson for the Department of Health said the government was "absolutely committed to ending new HIV transmissions within England by 2030".
They said the opt-out testing programme had been "highly successful" and that the department would "outline how we can build on this success".
