Over 100 people in Hertfordshire who tested positive for HIV were diagnosed late and faced an increased risk of death, figures covering a three-year period show.

Sexual health charity the Terrence Higgins Trust says Channel 4 drama It's A Sin – which covers the 1980s AIDS crisis – has helped boost HIV testing, but there is still more work to be done.

Public Health England data shows that out of 130 people aged 15 and over who tested positive for HIV in Hertfordshire, 60 were diagnosed late between 2017 and 2019.

Across England, 3,870 of 8,979 tests were recorded as a late diagnosis over the same period – 43 per cent.

PHE figures also show that in 2019, 26 per cent of 22,700 people in Hertfordshire who used specialist sexual health services missed the opportunity to get tested at a clinic through either not being offered an appointment or by declining one.

The Terrence Higgins Trust says HIV testing should be made standard, with checks carried out when a person registers for a GP or attends A&E.

It added that new drama It's a Sin, which has already received 6.5 million views, had already helped with a record number of tests ordered as part of National HIV Testing Week last week.

The five-part television series tells the story of a group of young, gay men in London at the height of the AIDS pandemic.

Terrence Higgins Trust chief executive, Ian Green, said: "We've seen the 'It's a Sin' effect on National HIV Testing Week with tests being ordered faster than ever before off the back of the series, including a surge following Olly Alexander's encouragement on social media for people to get tested.

"That's a brilliant legacy for the series."

But he added: "We firmly believe that there needs to be much more testing right across the country to find those living with undiagnosed HIV and there should never be a postcode lottery on access.

"Testing for HIV must become like having your eyes tested or a check-up at the dentist and the opportunities made available for that to happen."

Across England, the late diagnosis rate has risen from 40 per cent between 2014 and 2016.

Late diagnosis is recorded by measuring the strength of a person's immune system at the point of the positive test result. The figures are for tests which provide cell count data within 91 days.

PHE says many people diagnosed late have had the infection for at least three years, increasing the likelihood of premature death.

Without treatment, HIV can lead to AIDS (acquired immune deficiency syndrome) which is a collection of symptoms resulting from a weakened immune system which leaves a person susceptible to life-threatening illnesses.

HIV is passed from person to person through body fluids such as semen or blood and is most commonly caught by having unprotected sex.

It cannot be spread through day-to-day contact like sharing cutlery or kissing.

In Hertfordshire, the rate of new HIV diagnosis was six cases per 100,000 people aged 15 and over in 2019.

This was below the average across the country, of eight per 100,000.

Clare Perkins, PHE's deputy director of priorities and programmes, said: "We urge those at risk of HIV to get tested regularly.

"Through early detection and treatment with antiretroviral therapy, people with HIV can expect to live as long as people without HIV."

She said that those at risk of HIV and STIs can still access services through sexual health clinics during the Covid-19 pandemic.