Criteria for interpreting the results obtained with the INNO-LIA strips; reactivity to none, one, or more of the specified antigens is interpreted as negative, indeterminate, or positive, as assigned. The positive samples are discriminated as HTLV-I or HTLV-II depending on the intensity of the color of the strips; e.g., if the env gp46-1 plus gag p19-1 bands are more intense than the env gp46-2 band, the sample is typed as HTLV-I.