Adult preferred minimum: 1 mL serum Adult absolute minimum: 0.5 mL serum Pediatric minimum: 0.15 mL serum

< 1.0 ug/mL = Antibody concentration not protective. Is greater than or equal to 1.0 ug/mL = Antibody to H. influenzae b detected. Suggestive of protection.

Recommend testing of pre/post vaccination sera when clinically indicated. "Pre" and 30-day "post" Haemophilus influenzae b vaccination samples should be submitted together for testing. "Post" sample should be drawn 30 days after immunization and must be received within 60 days of "pre" sample. Please clearly mark samples "pre-vaccine" or "post-vaccine" so that samples will be saved and tested simultaneously.

Responder status is determined according to the ratio of post-vaccination concentration to pre-vaccination concentration of Haemophilus influenza b antibody, IgG as follows: 1. If the post-vaccination concentration is < 3.0 µg/mL, the patient is considered to be a nonresponder. 2. If the post-vaccination concentration is greater than or equal to 3.0 µg/mL, a patient with a ratio of greater than or equal to 4 is a good responder, a ratio of 2-4 is a weak responder, and a ratio of < 2 is considered a nonresponder.