Carriage of Neisseria meningitidis and Neisseria lactamica in Infants and Children

Abstract

Asymptomatic carriage of Neisseria meningitidis and Neisseria lactamica was studied in a total of 2,969 healthy infants and children in Danbury, Conn., between October 1971 and June 1975. The prevalence of N. meningitidis averaged 0.71% during the first four years of life and increased to 5.4% by 14--17 years. Rates of carriage of N. lactamica increased from 3.8% in three-month-old infants to a peak of 21.0% at 18 months and then declined to 1.8% by 14--17 years of age. Of the children who acquired N. lactamica, 66% developed fourfold or greater rises in titers of IgG antibody to groups A, B, and/or C meningococci as determined by immunofluorescence compared with only 5% of control children. Of new carriers of N. lactamica, 40% developed increased titers of bactericidal antibody to groups A, B, and/or C meningococci as compared with 7% of noncarriers. Carriage of N. lactamica may assist in the development of natural immunity to N. meningitidis by induction of cross-reactive antibodies.

The natural history of meningococcal carriage and disease

“…Over 5500 individuals were swabbed in this study (n=5652) and these data, stratified by age and serogroup form the basis of the carriage dataset for the following analyses. Because few young children were sampled in Stonehouse (three children <1 year old, 282 children aged 1-4 years), carriage data from <5-yearolds from a study by Gold et al [3], conducted in Danbury, Connecticut in 1972 (n=3787) was used to supplement the dataset (Table 1, Fig. 1).…”

“…We assumed there was no immunity to carriage and that individuals carried only one strain at a time. The duration of carriage was assumed to be 9 months [6] for meningococcal carriage and 4 months [3] for N. lactamica carriage, according to the published literature. The sensitivity of the results to changes in the duration of carriage was tested, including a shorter duration of carriage with serogroup C than other meningococcal serogroups.…”

“…N. meningitidis carriage strains are diverse and only a subset of these (known as hyperinvasive lineages) cause disease. Asymptomatic infection with pathogenic and non-pathogenic strains, including the closely related Neisseria lactamica, which is carried frequently in children, may help contribute to the development of protection against meningococcal disease [2,3]. However, large-scale carriage studies are expensive and difficult to conduct, limiting the availability of these data.…”

The PorB porin from commensal Neisseria lactamica induces Th1 and Th2 immune responses to ovalbumin in mice and is a potential immune adjuvant

“…Our work is focused on porin from Neisseria lactamica (a commensal bacterium which most frequently colonizes the nasopharynges of children [52,53]) and is aimed at characterizing its potential effect as an adjuvant of the immune system and its mechanism of action.…”

Effectiveness of different policies in preventing meningococcal disease clusters following a single case in day-care and pre-school settings in Europe

“…The higher the numbers of children treated, the higher the risk of adverse events and development of antimicrobial resistance [6,7]. Moreover, the widespread use of antibiotics would be expected to clear carriage of Neisseria lactamica in children, potentially interfering with natural development of immunity against meningococcal infection [8]. An alternative policy, as adopted in one country, would be to restrict prophylaxis to a subgroup of children of similar age sharing the same room within a nursery.…”