HIV infection can generally be broken down into four stages:

Primary or acute infection
This stage starts shortly after being exposed to HIV and lasts for a few weeks. During this time there would normally be a large amount of HIV in your blood (giving you what is called a high viral load). Your immune system responds to the HIV in your blood by starting to produce HIV antibodies. This process is called seroconversion, and the HIV antibodies produced by your immune system are what the standard HIV test looks for.

During this process, some people experience what’s known as seroconversion illness with symptoms such as fever, sore throat, fatigue, night sweats and a rash. Others, however, don’t experience any symptoms at all, and their seroconversion goes completely unnoticed. As well as a high viral load, your CD4 count during this stage usually drops very low. In most cases the high viral load and low CD4 count is only temporary and so after seroconversion you could expect to see your viral load drop and your CD4 count rise again.

Asymptomatic infection
This stage can last for several years, although this can differ greatly from person to person. During this time you would expect to have very few or no major symptoms of HIV infection (you would be asymptomatic). Although during this stage the HIV viral load in your blood would normally be quite low, HIV remains active in your lymph glands (or lymph nodes). Lymph glands form part of your immune system and are involved in the production of white blood cells which help to fight infection. As HIV remains active in your lymph glands they produce white blood cells to fight the infection, so you may notice that your glands are swollen from time to time. The lymph glands in your body that you can feel are situated in your armpits, groin and neck.

Symptomatic infection
Towards the end of the asymptomatic stage, HIV begins to become more active in your blood. Eventually your body cannot produce new CD4 cells quickly enough to keep up with the rate that HIV is destroying them. During this stage you would notice from your test results your HIV viral load starting to increase and at the same time your CD4 count beginning to fall. When monitoring your HIV, your doctor would notice your viral load increasing over a few months and take this as an indication that HIV is becoming more active in your blood.

As your CD4 count falls further, you and your doctor would probably begin to talk about starting HIV treatment. Treatment is very effective in stopping HIV from replicating, and in turn stopping and then reversing the increase in your viral load. If you don’t start treatment in time, then at this stage you would begin to notice some symptoms developing (you would be symptomatic). These symptoms vary from person to person, and would be an indication that you are starting to develop one or more opportunistic infections or tumours.

Advanced HIV disease (AIDS)
If you still had not started treatment, HIV would continue to replicate faster and faster, and your CD4 count would continue to fall. Symptoms of opportunistic infections or tumours that may have begun in the symptomatic infection stage would get more and more severe. This is because your immune system would now be severely damaged and it would have lost its ability to fight these infections. You would now be diagnosed with AIDS, and without first treating the infections and then starting anti-HIV treatment, these infections would eventually be fatal.

Some men who do not know they have HIV don’t find out until they start to develop symptoms. Sometimes these men are diagnosed with HIV and AIDS at the same time. Starting treatment as soon as possible is vital at this stage, but doctors sometimes want to treat the infection or illness first before starting anti-HIV drugs.

It used to be the case that once you’d been diagnosed with AIDS that diagnosis could not be reversed, even if your immune system recovered. An AIDS diagnosis would have been with you for good. However this is no longer the case, and these days doctors are moving away from the term AIDS, preferring instead to talk about advanced HIV disease.