Epidemiology & Infection: Volume 31 -

The Phases of Haemophilus pertussis
P. H. Leslie, A. D. Gardner
Published online by Cambridge University Press:

15 May 2009, pp. 423-434
- Article
- - You have access
- PDF
- Export citation
Haemophilus pertussis is a uniform species, without fixed varieties or “types.”
After isolation from the human subject it tends to pass through a series of antigenically distinct phases, of which the first two are toxic to guinea-pigs, whereas the last two are relatively harmless. The former probably correspond to the smooth, the latter to the rough phase of other bacteria.
The phase-changes are, up to a point, reversible.
Experiments on guinea-pigs have produced some evidence that the toxic Phase I is the best and perhaps the only antigen for the production of active immunity in guinea-pigs.

Epidemiology & Infection