THOUSANDS of people in Nottingham could have potentially fatal infections such as hepatitis and HIV – but not know it.
The NHS says as many as 3,000 people in the city may have one or more blood-borne infections.
Hepatitis B and C and HIV can be spread though sex with an infected person, sharing needles or through a broken area of skin.
And 80% of sufferers – around 2,400 people – may not know they have them.
GPs are now routinely testing "at-risk" people from countries with high rates of blood-borne viruses, those who inject drugs or the sexual partners of sufferers.
And experts are calling for people in such groups to get themselves tested – to avoid putting themselves and others at risk.
Mick Mason of sexual health charity the Terrence Higgins Trust said those at risk should get tested as early as possible. "The earlier you can get people diagnosed, the less risk there is of passing it on," he said.
People can get test results for HIV within 20 minutes and for hepatitis B and C within a week from the charity's base at Barker Gate, the Lace Market.
The number of people thought to have HIV has risen sharply in recent years, with 428 new cases in 2007.
Infections rates have gone up in Nottingham due, in part, to people from countries with higher rates of blood-borne viruses coming to the city.
Hepatitis B and C are infections of the liver caused by a virus, which can cause significant damage if left untreated.
Human immunodeficiency virus (HIV) is a virus that attacks the body's immune system. It leaves an infected person with a high risk of developing a serious infection or disease, such as cancer.
Mr Mason contracted HIV as well as Hepatitis B and C in 1983 from contaminated blood plasma. "We do see more and more cases of cross-infection, when someone has hepatitis and HIV," he said.
"That is an added complication because the two conditions accelerate each other and the treatments have an adverse effect on the other condition."
The rise in the number of blood-borne virus cases was revealed in the annual report of the primary care trust's director of public health, Chris Packham.