Oral Haemophili

Abstract

IT has been known for many years that haemophili can be isolated from the mouth. Pritchett and Stillman (1 9 19), for example, recovered these organisms from 55 of 231 saliva specimens, and Fleming and Maclean (1930), in one of the earliest studies in which an antibiotic was utilised for selective isolation, concluded that haemophili were part of the normal flora.Despite this, recent monographs and textbooks that contain detailed accounts of the bacteriology of the mouth either fail to mention haemophili at all (Bisset and Davis, 1960; Nolte, 1968) or state that they are occasionally present in small numbers (Burnett and Scherp, 1968). In this laboratory, haemophili are isolated by routine methods from approximately one-third of all oral clinical specimens submitted for investigation. No special methods are employed to recover haemophili, and indeed most strains are detected simply because their colonies resemble those of beta-haemolytic streptococci. Of 424 consecutively isolated strains 385 (90.8 per cent.) were identified as Haemophilus parahaemolyticus and 39 (9.1 per cent.) were non-capsulated H . influenzae.

An analysis of the diversity ofHaemophilus parainfluenzaein the adult human respiratory tract by genomic DNA fingerprinting

“…The other species isolated were H. inftuenzae (2), H. parahaemolyticus (6), H. paraphrohaemolyticus (3) and H. segnis (1) depth by fingerprinting at least 25 colonies each from samples collected in March and July from subjects A and B. This revealed carriage of from 5-8 differentiable haemophilus strains from up to three different species, with the majority of isolates from each sample being H. parainfluenzae (Table 1).…”

“…While H. influenzae is undoubtedly the most important potential pathogen, in health H. parainfluenzae accounts for the single largest proportion of Haemophilus species in the pharynx at all ages [5] and in the adult oral cavity [6,7] parainfluenzae are reported sporadically, the most common being meningitis, endocarditis and pneumonia [8]. Its role in respiratory infection has been reported as indistinguishable from that caused by non-capsulate H. influenzae [9,10], with one observation from the developing world indicating that 10 % of haemophilus isolates from the blood of children with lower respiratory infection were H. parainfluenzae [11].…”

Numerical Taxonomy of Haemophilus and Related Bacteria

“…As noted, fuller study may reveal subgroups representing H. ha e m oglo b in u p h il us and some additional species. Strains of Haemophilus may be much more common in normal persons than is often thought (49), and new species may be found if looked for. If for the present the three clusters are treated as species, their correct names appear to be as follows: cluster 1, Haemophilus influenzae; cluster 2, Haemophilus parainfluenzae ; cluster 3, Haemophilus aphrophilus.…”

Relationships of Nontypeable Haemophilus influenzae Strains to Hemolytic and Nonhemolytic Haemophilus haemolyticus Strains

“…Therefore, distinguishing H. influenzae from other bacterial species infecting normally sterile sites (i.e., the middle ear or blood) can be done reliably by determining X and V growth factor dependence. The differentiation of H. influenzae from H. haemolyticus in culture specimens potentially contaminated by the pharyngeal microbiome may still rely, in part, on determining the absence of beta-hemolysis, since the prevalence of hemolytic H. haemolyticus strains in specimen collections is highly variable and ranges from 0 to 51% (5,30,40,51). In contrast, a beta-hemolytic phenotype would not be useful in differentiating nonhemolytic H. haemolyticus strains, which are now know to be significantly prevalent in the pharyngeal cavities of healthy children and of adults with COPD (40,62).…”