HIV: Symptoms, Causes, Testing and Treatment

What is HIV?

HIV (Human Immunodeficiency Virus) is a virus that weakens your immune system, making it harder for your body to fight infections and illnesses. It is carried in the blood and bodily fluids of an infected person and can be transmitted through unprotected sex. This is why HIV is classified as a sexually transmitted infection (STI).

If left untreated, HIV can progress over many years to cause AIDS (Acquired Immune Deficiency Syndrome). AIDS severely damages the immune system, making even common infections potentially life-threatening.

Although there is no cure for HIV, with early diagnosis and proper treatment, people living with HIV can lead long, healthy lives.

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How is HIV transmitted?

HIV is spread through infected bodily fluids, such as blood, semen, vaginal fluid, anal mucus, and breast milk. The most common ways HIV is transmitted include:

  • Having vaginal or anal sex without a condom or other protection

  • Sharing unwashed or contaminated sex toys

  • Less commonly, through oral sex (although the risk is significantly lower)

HIV is not transmitted through casual contact, such as hugging, sharing utensils, or kissing.

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Symptoms of HIV

Many people with HIV do not realise they have it because symptoms can be mild or non-existent in the early stages. Within two to six weeks of infection, some people experience flu-like symptoms, including:

  • Fever

  • Sore throat

  • Rash

  • Fatigue

  • Aches and pains

  • Swollen glands 

Because these symptoms are so easy to miss or mistake for something else, testing for HIV as part of a sexual health screen is important, early diagnosis means treatment can start sooner.

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Frequently asked questions

Here are direct answers to some of the most frequently asked questions about HIV.

There’s currently no cure for HIV, despite ongoing HIV cure news and research into potential breakthroughs. What is available is highly effective HIV treatment — antiretroviral therapy (ART) — which can reduce the virus to undetectable levels and allow people to live long, healthy lives.

Pre-exposure prophylaxis (PrEP) is taken before potential exposure to prevent infection in the first place, while post-exposure prophylaxis (PEP) is an emergency course started after a possible exposure. Both work to prophylax against the virus taking hold, but PrEP is an ongoing preventive measure, whereas PEP needs to be started as soon as possible — ideally within 72 hours.

If left untreated, HIV can move from an acute-retroviral stage through a chronic phase to more advanced, immunosuppressive disease — what’s classed as AIDS. This retroviral illness means the immune system struggles to fight off opportunistic infections such as PCP (a type of pneumonia) or CMV (cytomegalovirus) — infections that wouldn’t usually cause serious illness. With effective treatment, most people’s immune systems can restore as they recover — even after a period of advanced illness — supported by an integrated care plan.

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