Prolonged Detection of Japanese Encephalitis Virus in Urine and Whole Blood in a Returned Short-term Traveler

Huang, G Khai Lin; Tio, Shio Yen; Caly, Leon; Nicholson, Suellen; Thevarajan, Irani; Papadakis, Georgina; Catton, Mike; Tong, Steven Y C; Druce, Julian

On the fourteenth day of illness, JEV immunofluorescence serology (Euroimmun) performed in parallel on plasma from day 7, day 12, and day 13 of illness, was positive. The JEV IgG titre increased across the serial bleeds from 160 to 1280 to >2560 (confirmed by neutralization), suggesting recent infection, and JEV IgM was detected in all 3 specimens. Serology performed on CSF from day 10 was also positive for JEV IgM and IgG. The presence of measles IgG in plasma but not CSF was consistent with local production of JEV antibodies in CSF rather than contamination. Serology for MVE (EIA-total antibody) was weakly positive on day 7 but negative on days 12 and 13 and thought to represent nonspecific cross-reactivity. Dengue virus IgM, IgG, and NS1 antigen were not detected.