Fig. 4

Flowchart of our newly established test algorithm for diagnosing HTLV-1 infection in Japan. Based on the results obtained in the performance evaluation of the HTLV-1 diagnostic serological assay kits commercially available in Japan, we established a novel HTLV-1 diagnostic test algorithm for use in Japan. This test algorithm includes a primary test with CLEIA, CLIA, ECLIA, or PA, a confirmatory test with LIA but not WB, and an additional confirmatory test with PCR when samples test indeterminate by LIA. How to judge the output of the test results and how to determine the infection status of a sample using the algorithm are shown on the flowchart