Home access test and all other ELISA tests are indirect tests, that is,they test for the presence of antibodies that are formed in response to HIV infection. Direct detection of the virus is very expensive and rarely done.
It does not matter whether the blood dries or not, if there are antibodies, they will be detected by appropriate tests such as [Home Access] ELISA.
This question has already been addressed in the HIV Forum earlier this month.
Please check and read under the main thread as:
'95 Sero ab negative, yet HIV positive? - tra96: 10/13/2006
Brian