Haemophilus influenzae in New Zealand: subtyping of isolates from invasive disease using outer membrane protein profiling.

Invasive Haemophilus influenzae type b disease affects one in every 350 New Zealand children by the age of five, leaving some with severe handicap. As part of a national surveillance programme aimed at determining the epidemiology of H influenzae b disease in this country, the diversity of local isolates causing invasive disease was examined using outer membrane protein (OMP) profiling. Of 81 H influenzae b isolates examined, 70 (86%) had identical OMP profiles. Among the other 11 H influenzae b isolates, eight different OMP profiles were observed. Nontype b Haemophilus influenzae isolates (n = 13) showed a greater diversity of OMP patterns.