A positive result does not necessarily rule out infection with a different Flavivirus
spp. Patients in the early stage of JEV infection may not have a detectable level of IgG antibody; IgG response may take several days or weeks to develop. In the absence of detectable IgG, testing for IgM-class antibody is strongly recommended. The best evidence of current infection is a significant change on two appropriately timed specimens with both tests performed in the same laboratory at the same time.
See Compliance Statement D
Statement D: This test was developed and its performance characteristics determined by ARUP Laboratories. The U.S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.