HIV is a virus which attacks the immune system and weakens the body's ability to fight everyday infections and disease, and just last year 4,363 people in the UK were newly diagnosed.
While HIV diagnoses have seen in a decline over the past decade, more than 3,000 males and 1,000 females were diagnosed with the virus in 2017, recent Government statistics show.
In Leeds, more than two in every 1000 adults are infected with HIV, but as many as 13 per cent of aren't even aware they have it.
What causes a HIV infection?
Most cases of HIV in the UK are typically caused by having unprotected anal or vaginal sex with a person who has the virus, says the NHS.
HIV is found in the body fluids of an infected person, including semen, blood and breast milk, and can be passed on to others even if they don't have any symptoms.
The virus can also be contracted by:
- Sharing needles, syringes and other injecting equipment
- From mother to baby before or during birth, or by breastfeeding
- Sharing sex toys with someone infected with HIV
- Healthcare workers accidentally pricking themselves with an infected needle
- Blood transfusion
It may also be possible to catch the virus through unprotected oral sex, although this risk is much lower.
What are the symptoms?
Around 80 per cent of people who have been infected with HIV experience short, flu-like symptoms around two to six weeks after infection.
This typically includes a raised temperature or fever, sore throat and a body rash.
Some may also experience tiredness, joint and muscle pain and swollen glands.
These symptoms usually last from one to two weeks, and are a sign that your immune system is trying to fight off the virus.
Experiencing these symptoms doesn't necessarily mean you have contracted the virus, but if you think you have been at risk of HIV infection within the past few weeks, it is advised you get an HIV test.
After the initial flu-like signs disappear, HIV may not cause any further symptoms for several years, but the virus continues to be active and causes progressive damage to your immune system.
Symptoms can then include:
- Weight loss
- Chronic diarrhoea
- Night sweats
- Skin problems
- Recurrent infections
- Serious life-threatening illnesses
Once you are infected with HIV it stays in the body for life, but treatment can keep the virus under control and immune system healthy.
Without medical treatment, people with HIV can develop AIDS.
Who is most at risk?
Certain groups of people are at higher risk of HIV infection and are advised to have regular tests.
- Men who have sex with men
- Black African heterosexuals
- People who share needles, syringes or other injecting equipment
How to test for HIV
GP surgeries, sexual health clinics, and clinics run by charities all offer HIV testing.
Clinics may offer a finger prick blood test which provides a quick result, but results from more detailed HIV tests may take up to a few days.
Home testing and sampling kits are also available to buy from pharmacies or online, and if the test does suggest you have HIV, a further blood test will need to be carried out to confirm this.
Both positive and negative HIV tests may need to be repeated one to three months after potential exposure to the virus.
Emergency anti-HIV medication (post-exposure prophylaxis) may also stop you from becoming infected if taken within 72 hours of possible exposure.
How to prevent HIV
The risk of HIV infection can be effectively reduced by taking the following measures:
- Using a condom for sex
- Taking pre-exposure prophylaxis medication if you are HIV negative, or if you are at substantial risk of contracting HIV
- Screening for HIV in pregnancy
Is there a cure?
There is currently no effective cure for HIV, although it can be controlled with medical treatment, known as antiretroviral therapy.
If taken every day, this medication can prolong the lives of many who are infected and help to keep them healthy, while lower the risk of spreading the virus to others.
If left untreated it can lead to AIDS, which is the most severe phase of HIV infection when the immune system can no longer fight infections.