Meningococcal carriage during a clonal meningococcal B outbreak in France

Abstract

The aim of this study performed in Normandy, France, was to analyze the pharyngeal meningococcal carriage at the peak of a clonal meningococcal B outbreak, which was subsequently controlled using an outer membrane vesicle vaccination. This cross-sectional study included randomly selected subjects aged 1-25 years. Carriers and non carriers were compared using unconditional logistic regression. Among the 3,522 volunteers, there were 196 (standardized rate: 6.46 %) Neisseria meningitidis carriers, of which there were only five with the outbreak strain (B:14:P1.7,16/ST-32; standardized rate: 0.18 %). From the multivariate analysis, older age, smoking, higher degree of socialization, and social deprivation appear to favor the carriage of all the strains included. Prior antibiotic treatment up to 12 months before swabbing, even with β-lactam, was protective against carriage. Our data indicate a low overall meningococcal carriage rate with a surprising protective effect of prior antibiotic exposure. The observed low carriage rate of the epidemic strain (B:14:P1.7,16/ST-32) contrasts with the high incidence of invasive meningococcal diseases (IMD) due to this strain. Hence, our data underline the high virulence of the strain and suggest a low level of natural immunity of the population against this strain. Although highly resource-consuming, carriage studies are helpful in guiding the implementation of control measures of IMD, such as mass vaccination or chemoprophylaxis.

Vaccination with a multicomponent meningococcal B vaccine in prevention of disease in adolescents and young adults

“…Higher GMTs in response to a third dose did not increase the percentage of subjects with hSBA titers ≥1:4 against NadA or fHbp, and it is unclear whether there is any clinical benefit of higher titers in response to the OMV component. Similar results were observed at 1 month after the 2-dose schedule both in the UK among 18-24 year old university students (99-100% achieved hSBA titers ≥1:4 against fHbp, NadA and PorA1.4) [47] and among [11][12][13][14][15][16][17] year old adolescents in Canada and Australia (99-100% achieved hSBA titers ≥1:5 against fHbp and NadA; 75% achieved hSBA titers ≥1:5 against PorA1.4) [43]. At two weeks after the second vaccination, 100% of subjects in the Canada and Australia study had hSBA titers ≥1:5 against strains fHbp and NadA; the percentage of subjects with hSBA ≥1:5 against strain NZ OMV at two weeks was higher compared to 1 month after vaccination (84-96%, 64-80%, respectively) [43].…”

“…bars, clubs), intimate contact (e.g. kissing, sharing drinks), smoking, and sleep deprivation [11][12][13]. While incidence peaks in adolescents are common in countries like the US, Canada, and Europe, some countries in Latin America do not exhibit such a prominent peak in its adolescent population [14][15][16][17].…”

Genetic Diversity and Levels of Expression of Factor H Binding Protein among Carriage Isolates of Neisseria meningitidis

“…This carriage study has been previously detailed [11]. It was approved by the Regional Ethical Committee for Medical Research (Comité de Protection des Personnes Nord-Ouest, CPP NordOuest) as well as the National French Data Protection Agency (Commission Nationale Informatique et Liberté).…”

Impact of MenBvac, an outer membrane vesicle (OMV) vaccine, on the meningococcal carriage

“…Our work is a nested study within a large carriage study performed during the first quarter 2008 among 1-25 years-old people randomly selected from the National Health Insurance data base in the six cantons of the Dieppe area [11]. Only children who could have the potential for being vaccinated during the vaccination campaigns were considered in the present study.…”

“…In early 2008, only 1-7 years-old children were vaccinated; around one third of them had received at least one dose of MenBvac [10]. At that time, a carriage study was performed at large scale among 1-25 years-old subjects of the epidemic area [11]. This situation offered the opportunity to evaluate the potential effect of MenBvac on meningococcal carriage by comparing vaccinated and unvaccinated children of the same age.…”