[buckle8017]

The false negative rate for HIV testing in newly infected people is actually pretty high, like 50% within the first few months high.

[ctoa]

No, it's not though. That's true for antibody tests commonly used for individuals because it's cheap. The window period for nucleic acid testing that is used for blood supply is very short. This test is similar to what's used to confirm a positive antibody test, but isn't used for individual testing because it is too expensive. Hence the pooling.