AFP and encephalitis: Serologic testing, which was performed for 21 (58.3%) patients, exclusively at commercial laboratories, had a median time from collection to result of 4 days (range: 2–16 days), was positive in 90.5% (n = 19) of cases, and the result was present at discharge for 85.7% (n = 18) of the patients, including 92.3% of encephalitis and 100% of AFP patients with serologic testing.