SERPINA1 and infection: Finally, some antibody-based diagnostic tests are available, and are effective and field applicable, such as the CATT test for HAT and VerY Diag for AAT, but antibody tests have a challenge in differentiating between active infection and exposure (additionally the CATT test only detects T. b. gambiense—there is currently no field-applicable test available for T. b. rhodesiense).