A viral load test measures the amount of HIV in a sample of blood and is used to monitor HIV infection and the effectiveness of antiretroviral therapy (ART) . The results of a viral load test are described as the number of copies of HIV RNA in a milliliter of blood, and the lower the number, the less virus there is in the blood. An undetectable viral load is generally considered to be less than 20 copies per milliliter of blood, and this is called viral suppression. Keeping your viral load low will keep your immune system healthy, make complications and opportunistic infections less likely, and help you live longer. A high viral load is generally considered about 100,000 copies, but you could have 1 million or more. A high viral load means the virus is growing, and your treatment is not working well. The higher the viral load, the more risk you have for infections and diseases related to a weak immune system, and it may also mean you have a higher risk for developing AIDS. An undetectable viral load means that you have so little HIV in your blood that the test cant find it, and this means that your HIV medicines are working well to protect your immune system, and you are unlikely to spread HIV through sex. However, it does not mean youre cured, and you must continue to take your medicines as prescribed to keep your HIV in control.