No you do not use a DUO test after nPEP, just an antibody test.
Very sorry for what happened to your wife.
You MUST use condoms until confirm your wife is OK. That is, as nursegirl said, 3 months after the last dose of the PEP. Altought the treatment drastically reduces the chance of infection (if she was infected, we hope not), there's still a risk.
A duo test is a 4th generation Elisa test which is currently used in most developed countries. This test look for both the antibodies against HIV and a specific HIV protein called p24 which is present during the first weeks of infection.
With this test, a result 6 weeks after a risk situation is a clear indication that the person is HIV negative. However, for the protocol, the test must be repeated 3 months after the risk situation. In your case, your wife can take this test 6 weeks after her last dose of PEP. If she is OK, then is 99% sure she will be OK in the 3 months test. Good luck.
THX nursegirl....what is the DUO test?? and how much time before she can be tested???? Is there any chance of me getting infected while having sex during she this treatment???
So sorry for what happened to your wife. Unfortunately, you will have to endure a 3 month wait for a conclusive result, however, in this situation, your wife could have a DUO test before that for peace of mind. The thing is, it is usually recommended to wait until the nPEP is complete to allow for an accurate result. She would need to test 3 months after her LAST dose of nPEP.
The fact that she was started on nPEP within the 72 hour window period is a great thing. nPEP can substantially reduce one's risk for HIV.
You need to follow the doctor's instructions about testing. And definitely seek some therapy for both of you to help you deal with what has happened.