Indirect enzyme-linked immunosorbent assay for the quantitation of the type-specific antigen of Haemophilus influenzae b: a preliminary report.

Infections with Haemophilus influenzae type b are major causes of morbidity and mortality in young children. We developed an enzyme-linked immunosorbent assay for the diagnosis of Hib infections. The ELISA was more sensitive than both counterimmunoelectrophoresis and latex agglutination for the detection of Hib antigen in serum, urine, and cerebrospinal fluid. In addition, no false positive ELISA reactions were noted. The increased sensitivity of ELISA was especially valuable in the detection of Hib antigen following antibiotic therapy, in which case cultures are often sterile and CIE and LA can be negative. ELISA is thus a valuable tool for the early diagnosis of Hib infections.