ABSTRACT
Cerebrospinal fluid specimens should be processed within an hour after collection or, if this is not feasible, inoculated into Trans-Isolate medium and transported at 20-25 C. Encapsulated strains may become confluent and demonstrate iridescence, particularly on clear agar. Nucleic acid amplification tests have been developed for the identification and speciation of cultured bacteria and to directly detect bacteria in blood, other normally sterile body fluids, and respiratory secretions. The genetic diversity and population structure of Haemophilus have been studied by a variety of techniques, including multilocus enzyme electrophoresis, ribotyping, pulsed-field gel electrophoresis and whole genome, 16S rRNA, and multilocus sequence typing. An alternative strategy for gene regulation is provided by simple contingency loci, which contain dior tetranucleotide tandem sequence repeats within or 5' to coding regions. Highly immunogenic polysaccharide-protein conjugate vaccines introduced in the 1980s have dramatically reduced the incidence of Hib infection among vaccinated children.
