HIV Explained

Checking my progress

Can I check how my HIV is progressing?

Your doctor will regularly undertake tests to see how your immune system is functioning. The two main tests measure your viral load and your CD4 cell count. The results of these tests allow your doctor to monitor how your HIV infection is progressing. Your doctor can then provide advice about when you should start treatment or alter the treatments you are taking.

Viral load

HIV multiplies by copying itself within your body. Your viral load indicates how active HIV is, damage to your immune system, risk of future damage to your immune system and risk of serious HIV-related infection. Your viral load also indicates how well your treatments are working or whether you should start treatment.

A viral load test is a simple blood test that measures the amount of HIV in your bloodstream. The lower your viral load, the better.

If your viral load is high and you start taking treatments, your viral load should go way down. Your doctor will aim to get it down to an ‘undetectable’ level. That means you still have HIV but there is so little it doesn’t show up in the usual tests.

An undetectable viral load will greatly reduce the risk of transmitting HIV although it does not eliminate it. A viral load test measures HIV in blood but your viral load can be higher in other body fluids such as semen and vaginal fluids particularly if you have a sexually transmissible infection. If you have maintained an undetectable viral load for six months or more, take your medication as prescribed, do not have any STIs, and have regular check-ups, you can be confident you will not pass on HIV through sexual intercourse. Talk to your doctor about your particular circumstances if you are thinking of relying on low viral load as a substitute for safe sex.

Understanding Viral Load


CD4 count

CD4 cells are a critical part of your immune system. A person with a healthy immune system usually has between 500 and 1500 CD4 cells per cubic millimetre of blood. HIV infects and destroys CD4 cells until they are so depleted your immune system does not work properly.

A CD4 test is a blood test that identifies how many CD4 cells you have and how strong your immune system is. If your CD4 count is low, you are more likely to get sick. If you go on treatment, your CD4 count should go up considerably, which will stop you from getting sick.

Doctors used to rely on your CD4 cell count to determine when you should start treatment. Now treatment is recommended for all people with HIV, however, treatment becomes increasingly urgent as CD4 count decreases. See Treatment.

Understanding your CD4 cell count


“I just needed to know what I am dealing with. I got an appointment with a specialist and that appointment could not come quick enough.”