What is the difference between a viral load test and a pcr test? Is one better than the other? Also, I read a symptom of hiv is purple or brown spots on or under the skin that look like bruises. What is it that actually causes these spots?


A viral load test measures HIV-1 RNA levels in the blood plasma. The polymerase chain reaction (PCR) is one method used to detect viral load or HIV DNA in blood cells. Your spots could be a variety of things.