Final answer:
HIV-positive patients not already on HAART should have their CD4 count and viral load measured every 3 to 6 months.
Step-by-step explanation:
The recommended interval for measuring CD4 count and viral load in HIV-positive patients who are not already on highly active antiretroviral therapy (HAART) is every 3 to 6 months. CD4 count measures the number of CD4 T cells, which are a type of white blood cell that plays a crucial role in the immune system. Viral load measures the amount of HIV RNA in the blood, indicating how active the virus is in the body.