Among the 46,363 suspected measles cases, the double-positive rate for measles-specific IgM and viral nucleic acid was 23.7% (11,011/46,363), the single-positive rate for measles-specific IgM was 6.5% (3,028/46,363), and the single-positive rate for viral nucleic acid was 4.2% (1,960/46,363). This evidence concerns the gene CD40LG and measles.