Rapid serogroup identification of Neisseria meningitidis by using antiserum agar: Prevalence of serotypes in a disease-free military population

Abstract

Nasopharyngeal cultures from 414 Marines were plated directly onto antiserum agar containing the antibiotics vancomycin, colistin, and nystatin for meningococcal isolation and serogroup identification. Meningococci were isolated from 267 Marines, giving a carrier prevalence of 64.5%. A total of 58% of the isolates could be placed into serogroups; of these 22.3% were group B, 4.7% were group C, 25.7% were group Y, 24.3% were group W135, and 23.0% were group 29E. No serogroup A organisms were recovered. Serotyping by agar gel double diffusion was perforned on 148 strains. More than 70% of these strains were nontypable, and the disease-associated serotype 2 was present only in two group Y isolates. The same 148 isolates were also classified by major outer membrane protein patterns after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Polyacrylamide gel electrophoresis pattern IV was most common among all serogroups. The data demonstrate the effective use of antiserum agar for meningococcal surveillance and document the frequency of specific serotypes and polyacrylamide gel electrophoresis types among carrier isolates obtained from a nonrecruit military population.

Natural bactericidal activity of human serum against Neisseria meningitidis isolates of different serogroups and serotypes

“…Meningococci from groups B, C, and Y presently account for the majority of disease isolates in the United States (20). In contrast to the high frequency of groupable disease isolates, from 20 to 50%o of throat isolates from asymptomatic carriers are nongroupable (NG) (1,2) and therefore probably non-encapsulated and presumably less pathogenic.…”

Early development in healthy children of serum opsonins against nonpathogenic Neisseria meningitidis

“…In addition, there are strains that are nongroupable, i.e. strains without recognized specific capsular polysaccharide antigens (6). Clinical meningococcal disease is generally caused by the serogroups A, B, C, occasionally by the serogroups W-135 and Y (17), whereas other serogroups and nongroupable strains are referred to as nonpathogenic meningococci.…”

A reference procedure to study chemiluminescence induced in polymorphonuclear leukocytes by Neisseria meningitidis

“…On the basis of capsular polysaccharide antigens, at least nine serogroups are recongnized, labelled A, B, C, D, X, Y, Z, W-135 and 29E; but there are also strains that are non-groupable, i.e. strains without recognized specific capsular polysaccharide antigens (5). Further subdivisions can be based on protein and lipopolysaccharide antigens located in the subcapsular outer membrane (7).…”