ART4 and infection: Both RABV antibodies to the glycoprotein and RNP have a proven role in the immune response after vaccination.53,54 Based on patient histories in the United States, RABV RNP binding antibodies are typically detected first by IFA in response to clinical infection, and rVNA may or may not be induced.38 These observations suggest an early response of antibodies to RNP relative to the induction of rVNA during CNS infection.