An outbreak of group B meningococcal disease: tracing the causative strain of Neisseria meningitidis by DNA fingerprinting.

SUMMARYIn a household survey in the Faroe Islands, an isolated community with hyperendemic occurrence of meningococcal disease due to serogroup B 15, 1604 persons were examined for pharyngeal carriage of Neisseria meningitidis and N. lactamica. Two areas were chosen having experienced high (HIA), and two having experienced low incidences (LIA) of disease. Living in HIA compared with LIA was associated with higher risk of N. meningitidis B 15 carriage and lower risk of N. lactamica carriage, with odds ratios of 2·7 (95% confidence interval (CI) 1·4–5·1, P = 0·003) and 0·41 (95% CI 0·31–0·53, P < 0·0001), respectively. In HIA the risk of N. meningitidis carriage was much lower in non-carriers than carriers of N. lactamica, with an odds ratio of 0·19 (95% CI 0·08–0·47, P = 0·0003); in LIA this association (odds ratio 0·51, P = 0·05) was much weaker. Children 0–14 years had substantially higher risk of being carriers of N. meningitidis group B 15 if the mothers were so, with an odds ratio of 11 (95% CI 4–29, P < 0·0001).

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Molecular surveillance ofNeisseria meningitidiscapsular switching in Portugal, 2002–2006

Epidemiology and Infection ◽

10.1017/s0950268808001106 ◽

2008 ◽

Vol 137 (2) ◽

pp. 161-165 ◽

Cited By ~ 16

Author(s):

M. J. SIMÕES ◽

M. CUNHA ◽

F. ALMEIDA ◽

C. FURTADO ◽

L. BRUM

Keyword(s):

Neisseria Meningitidis ◽

Genetic Relationship ◽

Meningococcal Disease ◽

Gel Electrophoresis ◽

Vaccination Schedule ◽

Pulsed Field Gel Electrophoresis ◽

Allelic Profile ◽

Molecular Surveillance ◽

Laboratory Surveillance ◽

Group B

SUMMARYNeisseria meningitidiscapsular switching has been reported in several countries. In order to establish the genetic relationship within group B and C strains expressing subtypes 2a or 2b, and to evaluate whether C to B capsular switching occurred in Portugal, 64 meningococci (56 serogroup C and 8 serogroup B) isolated from invasive meningococcal disease were typed using molecular methods. The studied phenotypes, 2b:P1.5,2 and 2a:P1.5-1,10-8, were the most frequent among serogroup C, but were uncommon among serogroup B strains. The multi-locus sequence typing (MLST) allelic profile and the pulsed-field gel electrophoresis (PFGE) fingerprints showed that seven serogroup B strains were genotypically identical to C strains, suggesting that capsular switching occurred. Active laboratory surveillance to find evidence of capsule switching is a now priority as MenC was introduced in the Portuguese vaccination schedule in January 2006.

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Potential Capsule Switching from Serogroup Y to B: The Characterization of Three suchNeisseria meningitidisIsolates Causing Invasive Meningococcal Disease in Canada

Canadian Journal of Infectious Diseases and Medical Microbiology ◽

10.1155/2005/216369 ◽

2005 ◽

Vol 16 (3) ◽

pp. 171-174 ◽

Cited By ~ 15

Author(s):

Raymond SW Tsang ◽

Dennis KS Law ◽

Shaun D Tyler ◽

Gwen S Stephens ◽

Mark Bigham ◽

...

Keyword(s):

Neisseria Meningitidis ◽

Meningococcal Disease ◽

Multilocus Sequence Typing ◽

Housekeeping Gene ◽

Sequence Type ◽

Invasive Meningococcal Disease ◽

Group B

Three group BNeisseria meningitidisisolates, recovered from meningococcal disease cases in Canada and typed as B:2c:P1.5, were characterized. Multilocus sequence typing showed that all three isolates were related because of an identical sequence type (ST) 573. Isolates typed as 2c:P1.5 are common in serogroup Y meningococci but rare in isolates from serogroups B or C. Although no serogroup Y isolates have been typed as ST-573, eight isolates showed five to six housekeeping gene alleles that were identical to that of ST-573. This suggested that the B:2c:P1.5 isolates may have originated from serogroup Y organisms, possibly by capsule switching.

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Effectiveness of meningococcal vaccines at reducing invasive meningococcal disease and pharyngeal Neisseria meningitidis carriage: A systematic review and meta-analysis

Clinical Infectious Diseases ◽

10.1093/cid/ciaa1733 ◽

2020 ◽

Author(s):

Mark McMillan ◽

Abira Chandrakumar ◽

Hua Lin Rachael Wang ◽

Michelle Clarke ◽

Thomas R Sullivan ◽

...

Keyword(s):

Neisseria Meningitidis ◽

Meningococcal Disease ◽

Incidence Rate Ratio ◽

Meta Analysis ◽

Membrane Vesicle ◽

Invasive Meningococcal Disease ◽

Meningococcal Vaccines ◽

Unpublished Studies ◽

Group B ◽

4Cmenb Vaccine

Abstract Background Invasive meningococcal disease (IMD), caused by Neisseria meningitidis, leads to significant morbidity and mortality worldwide. This review aimed to establish the effectiveness of meningococcal vaccines at preventing IMD and N. meningitidis pharyngeal carriage. Methods A search within PubMed, Embase, Scopus, and unpublished studies up to 1st February 2020 was conducted. Results After removal of duplicates, 8565 were screened and 28 studies included. Protection was provided by meningococcal C vaccines for group C IMD (odds ratio (OR) 0·13 [95% CI, 0·07-0·23]), outer membrane vesicle (OMV) vaccines against group B IMD (OR 0·35 [0·25-0·48]), and meningococcal ACWY (MenACWY) vaccines against group ACWY IMD (OR 0·31 [0·20-0·49]). A single time series analysis found a reduction following an infant 4CMenB program (incidence rate ratio, 0·25 [0·19-0·36]). Multivalent MenACWY vaccines did not reduce carriage (relative risk [RR] 0·88 [0·66-1·18]), unlike monovalent A (RR 0·73 [0·61-0·85]), and C vaccines (RR 0·50 [0·26-0·97]). 4CMenB vaccine had no effect on group B carriage (RR 1·12 [0·90-1·40]). There was also no reduction in group B carriage following MenB-FHbp vaccination (RR 0.98 [0.53-1.79]). Conclusions Meningococcal conjugate C, ACWY, and OMV vaccines are effective at reducing IMD. A small number of studies demonstrate that monovalent C and A conjugate vaccines reduce pharyngeal N. meningitidis carriage. There is no evidence of carriage reduction for multivalent MenACWY, OMV, or recombinant meningococcal B vaccines, which has implications for immunisation strategies. Registration PROSPERO CRD42018082085

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An outbreak of serogroup B:15:P1.16 meningococcal disease, Frederiksborg county, Denmark, 1987–9

Epidemiology and Infection ◽

10.1017/s0950268800049463 ◽

1992 ◽

Vol 108 (1) ◽

pp. 19-30 ◽

Cited By ~ 14

Author(s):

S. Samuelsson ◽

P. Ege ◽

L. Berthelsen ◽

I. Lind

Keyword(s):

Mortality Rate ◽

Neisseria Meningitidis ◽

Meningococcal Disease ◽

Age Group ◽

Household Contacts ◽

Epidemiological Features ◽

Time Space ◽

Prophylactic Measures ◽

Group B ◽

Overall Mortality

SUMMARYEpidemiological features of an outbreak of group B:15:P1.16 meningococcal disease (MD) in Frederiksborg country, Denmark, 1987–9, were investigated. The study comprised 149 cases notified during the outbreak and the two preceding years; 115 were confirmed by the isolation of Neisseria meningitidis. In 1989 the incidence had increased to 14·1 per 100 000 population. Among group B strains, B:15:P1.16 accounted for 80% (77/97). The overall mortality rate was 10% (15/149). Regarding cases due to group B:15:P1.16 strains a significant time-space clustering, which exclusively occurred within the 10–19 years age group, was demonstrated. The link between cases within clusters was indirect or unknown, except for ten patients with contact to one particular school. The prophylactic measures used included administration of rifampicin to household contacts. During the outbreak the proportion of secondary cases was high (6–15%). All secondary cases occurred outside the household indicating that the household had been protected.

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Immunity to Neisseria meningitidis Group B in Adults despite Lack of Serum Bactericidal Antibody

Clinical and Vaccine Immunology ◽

10.1128/cvi.00341-07 ◽

2007 ◽

Vol 14 (12) ◽

pp. 1596-1602 ◽

Cited By ~ 33

Author(s):

Jo Anne Welsch ◽

Dan Granoff

Keyword(s):

Neisseria Meningitidis ◽

Bactericidal Activity ◽

Meningococcal Disease ◽

Whole Blood ◽

Thrombin Inhibitor ◽

Blood Samples ◽

Blood Assay ◽

Bactericidal Antibody ◽

Bactericidal Activities ◽

Group B

ABSTRACT Serum-complement-mediated bactericidal antibody (SBA) remains the serologic hallmark of protection against meningococcal disease, despite experimental and epidemiologic data that SBA may underestimate immunity. We measured bactericidal activity against three strains of Neisseria meningitidis group B in sera from 48 healthy adults and in whole blood from 15 subjects. Blood was anticoagulated with lepirudin, a specific thrombin inhibitor not known to activate complement. Depending on the test strain, protective SBA titers of ≥1:4 were present in only 8 to 15% of the subjects, whereas bactericidal activity was present in 40 to 87% of subjects according to the blood assay. Among SBA-negative subjects, blood from 23 to 42% gave a decrease of ≥2 log10 CFU/ml after 1 h of incubation, and blood from 36 to 83% gave a decrease of ≥1 log10 after 2 h. For most blood samples, bactericidal antibodies primarily were directed against noncapsular antigens, since activity was not inhibited by group B polysaccharide. For some SBA-negative subjects, white cells were not needed, since similar respective bactericidal activities were observed in blood and plasma. Bactericidal activity by whole blood of SBA-negative subjects can be rapid (<1 h) and effective (≥2 log10) and, among all subjects, was four- to sixfold more prevalent than a positive SBA. Thus, while an SBA titer of ≥1:4 predicts protection against meningococcal disease, a titer of <1:4 is poorly predictive of susceptibility. More sensitive assays than SBA are needed to assess protective meningococcal immunity, or we risk underestimating the extent of immunity in the population and the effectiveness of new meningococcal vaccines.

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Serotypes of Neisseria meningitidis isolated from patients in Norway during the first six months of 1978

Journal of Clinical Microbiology ◽

10.1128/jcm.9.2.186-188.1979 ◽

1979 ◽

Vol 9 (2) ◽

pp. 186-188 ◽

Cited By ~ 1

Author(s):

E Holten

Keyword(s):

Neisseria Meningitidis ◽

Meningococcal Disease ◽

Group A ◽

Group B

During the first 6 months of 1978, 114 strains of Neisseria meningitidis isolated from patients in Norway were serotyped. Among 27 group C strains, type 2 was most common, whereas 82% of the 82 group B isolates did not react with antisera to the standard serotypes 1 to 12. These strains were shown to belong to a new serotype, type 15. Also some group A and C strains had the type 15 antigen. Investigations on a possible immunoprophylaxis against group B meningococcal disease in Norway should accordingly proceed with type 15 rather than with type 2 meningococci.

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Serotypes among Neisseria meningitidis serogroups B and C strains isolated in Canada

Canadian Journal of Microbiology ◽

10.1139/m80-245 ◽

1980 ◽

Vol 26 (12) ◽

pp. 1480-1488 ◽

Cited By ~ 9

Author(s):

F. E. Ashton ◽

A. Ryan ◽

B. B. Diena ◽

A. M. R. MacKenzie ◽

F. Chan

Keyword(s):

Neisseria Meningitidis ◽

Meningococcal Disease ◽

Double Diffusion ◽

Agar Gel ◽

Virulence Marker ◽

Group B

Antisera made to prototype serogroup B strains of Neisseria meningitidis were used to serotype, by agar gel double diffusion, 262 meningococcal serogroups B and C strains isolated in Canada. The strains included 93 from patients and 169 from carriers. Serotype 2 was associated with 39 of 75 (52%) of group B strains and 14 of 18 (77.8%) of group C strains isolated from patients. The group B strains were mainly (87.2%) serotype 2b, while the majority (92.2%) of group C strains was serotype 2a. Other serotypes (including a new provisional serotype) represented 25.3 and 5.5% of groups B and C strains, respectively. The new serotype accounted for 13% of the group B strains. Approximately 23% of the strains isolated from patients were nontypable. The distribution of serotype 2, nontype 2 (other serotypes), and nontypable strains isolated from carriers was 2.1, 36.6, and 61.3%, respectively, for group B meningococci and 22.2, 29.6, and 48.2%, respectively, for group C meningococci. Serotype 11 was the most prominent of the strains isolated from carriers. Approximately 7% of all the strains were multiple serotypes. Serotype 2 is an important virulence marker associated with meningococcal groups B and C disease in Canada, with serotypes 2a and 2b being markedly associated with groups C and B meningococcal disease, respectively.

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The panmictic nature ofNeisseria meningitidisserogroup B during a period of endemic disease in Canada

Canadian Journal of Microbiology ◽

10.1139/w01-008 ◽

2001 ◽

Vol 47 (4) ◽

pp. 283-289 ◽

Cited By ~ 8

Author(s):

Fraser E Ashton ◽

Dominique A Caugant

Keyword(s):

Genetic Diversity ◽

Cluster Analysis ◽

Neisseria Meningitidis ◽

Meningococcal Disease ◽

Enzyme Electrophoresis ◽

Endemic Disease ◽

Multilocus Enzyme Electrophoresis ◽

Common Serotypes ◽

The Mean ◽

Group B

Three hundred and one (301) strains of Neisseria meningitidis serogroup B, isolated from patients with meningococcal disease during the years 19941996, were subjected to multilocus enzyme electrophoresis, serotyping, and serosubtyping. Based on the analyses of 14 enzyme loci, 177 electrophoretic types (ETs) were identified. Of these, 136 were represented by single isolates and 41 were represented by multiple isolates (range 231). The mean genetic diversity for isolates was 0.444 and for ETs was 0.440. The index of association (IA) between loci was 0.530 ± 0.08 for isolates and 0.256 ± 0.10 for ETs. Cluster analysis revealed the presence of 39 lineages each represented by a single ET or clusters of ETs. The most common serotypes were 4, 15, and 14 and accounted for 84 (28.0%), 53 (17.6%), and 32 (10.6%) of the isolates, respectively, and were dispersed amongst 46 ETs (1122), 35 ETs (3165), and 26 ETs (1876), respectively. The 109 (36.6%) nontypable (NT) isolates were amongst 74 ETs (6177). The mean genetic diversity for serotypes 4, 15, and 14 and NT isolates was 0.368, 0.371, 0.343, and 0.442, respectively, and for ETs was 0.363, 0.354, 0.397, and 0.440, respectively. Combinations of serotypes and serosubtypes (number of isolates) that occurred most frequently were 4:P1.14 (17), 14:P1.16 (16), NT:P1.16 (16), 15:P1.16 (13), and NT:P1.13 (13). The majority of group B disease in Canada during 19941996 was caused by meningococci of considerable genetic diversity, and reflects a situation of endemic disease. However, the results also indicate that organisms belonging to the ET-5 complex, which has been responsible for outbreaks of group B disease globally for several decades, have been introduced into the country.Key words: meningococcal, genotypes, serotypes, serosubtypes, Neisseria meningitidis.

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