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D. Caugant

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Seroepidemiological Study after a Long-Distance Industrial Outbreak of Legionnaires' Disease

Clinical and Vaccine Immunology, 2009

Following a long-distance outbreak of Legionnaires' disease from an industrial air scrubber i... more Following a long-distance outbreak of Legionnaires' disease from an industrial air scrubber in Norway in 2005, a seroepidemiological study measuring levels of immunoglobulin G (IgG) and IgM antibodies to Legionella pneumophila was performed with a polyvalent enzyme-linked immunosorbent assay. One year after the outbreak, IgG levels in employees (n = 213) at the industrial plant harboring the scrubber and in blood donors (n = 398) from the outbreak county were low but significantly higher (P ≤ 0.002) than those in blood donors (n = 406) from a nonexposed county. No differences in IgM levels among the three groups were found after adjustment for gender and age. Home addresses of the seroresponders in the exposed county clustered to the city of the outbreak, in contrast to the scattering of addresses of the seroresponding donors in the nonexposed county. Factory employees who operated at an open biological treatment plant had significantly higher IgG and IgM levels (P ≤ 0.034) than...

Genotypic Relationships Among Strains Classified under the (Pasteurella) haemolytica-complex as Indicated by Ribotyping and Multilocus Enzyme Electrophoresis

Zentralblatt für Bakteriologie, 1997

Two-hundred and one strains classified under the (Pasteurella) haemolytica-complex isolated from ... more Two-hundred and one strains classified under the (Pasteurella) haemolytica-complex isolated from cattle, sheep, deer, pigs, hares and rabbits were investigated by ribotyp ing. Fifty-nine of these strains were selected for further studies using multi locus enzyme electrophoresis (MEE). A correlation between the clusters identified by ribotyping and MEE was demonstrated and the results furthermore indicated that a genetic basis ex ists for most clusters previously outlined by the use of quantitative evaluation of phe notypic data. The taxonomic relevance of ornithine decarboxylase and fermentation of L-arabinose, D-sorbitol and glucosides for taxonomic delineation within the (P.) haemolytica-complex was supported. A taxonomic importance was further indicated for ONPG, ONPX, ONPF, meso-inositol, D-xylose, maltose, dextrine and NPG in re lation to some of the taxa. Within the porcine taxon 15, however, differences in orni thine decarboxylase did not correspond to genetic clusters. Six lineages were revealed by MEE. Lineage A contained electrophoretic types (ETs) representing biogroups 1, 3A-3H, 8A and 9, indicating a genetic relationship between these groups-an observation which was supported by ribotyping. Lineage B includ ed biogroup 8D, 3 strains from biogroup 10 and a single strain from biogroup 1 and taxon 18/biovar 1. Lineage C contained strains allocated to biogroup 6 from rumi nants and the porcine taxon 15. The similarity between these two groups was accen tuated by ribotyping. Lineage D and the single isolate in lineage E contained strains al located to biogroups 7, 10, 8B and 8C, in addition to single strains from biogroups 6 334 0. Angen et al. and 9. The same strains were found in the heterogenous ribotype cluster 17. Lineage F contained strains representing the leprine taxon 20 and the ruminant (P.) granulo matis. Ribotyping indicated that the ruminant biogroup 3J was affiliated with both taxon 20 and (P.) granulomatis.

The first large epidemic of meningococcal disease caused by serogroup W135, Burkina Faso, 2002

Vaccine, 2007

In 2001 a significant proportion of cases of meningococcal meningitis toward the end of a serogro... more In 2001 a significant proportion of cases of meningococcal meningitis toward the end of a serogroup A epidemic in Niger and Burkina Faso was found to be caused by serogroup W135 meningococci. The World Health Organization put in place in several African countries an extended surveillance scheme in preparation for a possible epidemic situation. In January 2002, the first large epidemic of meningococcal disease caused by serogroup W135 started in Burkina Faso, resulting in more than 12,000 cases and 1400 deaths. We report here the results of the laboratory-based surveillance and the characteristics of the epidemic clone.

Multilocus sequence typing and ftsI sequencing: a powerful tool for surveillance of penicillin-binding protein 3-mediated beta-lactam resistance in nontypeable Haemophilus influenzae

BMC Microbiology, 2014

Background: Beta-lactam resistance in Haemophilus influenzae due to ftsI mutations causing altere... more Background: Beta-lactam resistance in Haemophilus influenzae due to ftsI mutations causing altered penicillin-binding protein 3 (PBP3) is increasing worldwide. Low-level resistant isolates with the N526K substitution (group II low-rPBP3) predominate in most geographical regions, while high-level resistant isolates with the additional S385T substitution (group III high-rPBP3) are common in Japan and South Korea. Knowledge about the molecular epidemiology of rPBP3 strains is limited. We combined multilocus sequence typing (MLST) and ftsI/PBP3 typing to study the emergence and spread of rPBP3 in nontypeable H. influenzae (NTHi) in Norway. Results: The prevalence of rPBP3 in a population of 795 eye, ear and respiratory isolates (99% NTHi) from 2007 was 15%. The prevalence of clinical PBP3-mediated resistance to ampicillin was 9%, compared to 2.5% three years earlier. Group II low-rPBP3 predominated (96%), with significant proportions of isolates non-susceptible to cefotaxime (6%) and meropenem (20%). Group III high-rPBP3 was identified for the first time in Northern Europe. Four MLST sequence types (ST) with characteristic, highly diverging ftsI alleles accounted for 61% of the rPBP3 isolates. The most prevalent substitution pattern (PBP3 type A) was present in 41% of rPBP3 isolates, mainly carried by ST367 and ST14. Several unrelated STs possessed identical copies of the ftsI allele encoding PBP3 type A. Infection sites, age groups, hospitalization rates and rPBP3 frequencies differed between STs and phylogenetic groups. Conclusions: This study is the first to link ftsI alleles to STs in H. influenzae. The results indicate that horizontal gene transfer contributes to the emergence of rPBP3 by phylogeny restricted transformation. Clonally related virulent rPBP3 strains are widely disseminated and high-level resistant isolates emerge in new geographical regions, threatening current empiric antibiotic treatment. The need of continuous monitoring of beta-lactam susceptibility and a global system for molecular surveillance of rPBP3 strains is underlined. Combining MLST and ftsI/PBP3 typing is a powerful tool for this purpose.

Clonal analysis of Escherichia coli O2:K1 isolated from diseased humans and animals

Infection and Immunity, 1986

Forty-six Escherichia coli isolates of serotype O2:K1 from human urinary tract infections, chicke... more Forty-six Escherichia coli isolates of serotype O2:K1 from human urinary tract infections, chicken sepsis, and bovine mastitis were obtained from laboratories in England, Denmark, Sweden, and Finland. The bacteria were compared for outer membrane protein (OMP) pattern, lipopolysaccharide pattern, electrophoretic mobilities of enzymes, and flagellar serotype and were tested for fimbriation, biotype, hydroxamate production, hemolysin production, antibiotic resistance, plasmid content, colicin production, and virulence in neonatal rats. Isolates from humans were assigned to two clonal groups; poultry isolates belonged to one of these clonal groups, whereas bovine isolates belonged to the other. Poultry and human isolates of the same clonal group could be distinguished only by their plasmid content. Strains within this group were heterogeneous with respect to biotype, fimbriation, virulence, and flagellar serotype. Human and bovine isolates of the second clonal group were distinguished ...

Serum antibody responses in Ethiopian meningitis patients infected with Neisseria meningitidis serogroup A sequence type 7

Clinical and Vaccine …, 2007

To elucidate critical components of protective immune responses induced during the natural course... more To elucidate critical components of protective immune responses induced during the natural course of serogroup A meningococcal disease, we studied acute-, early-convalescent-, and late-convalescent-phase sera from Ethiopian patients during outbreaks in 2002 to 2003. Sera were obtained from laboratory-confirmed patients positive for serogroup A sequence type 7 (ST-7) meningococci (A:4/21:P1.20,9) (n ‫؍‬ 71) and from Ethiopian controls (n ‫؍‬ 113). The sera were analyzed using an enzyme-linked immunosorbent assay to measure levels of immunoglobulin G (IgG) against serogroup A polysaccharide (APS) and outer membrane vesicles (OMVs) and for serum bactericidal activity (SBA) using both rabbit and human complement sources. Despite relatively high SBA titers and high levels of IgG against APS and OMVs in acute-phase patient sera, significant increases were seen in the early convalescent phase. Antibody concentrations returned to acutephase levels in the late convalescent phase. Considering all patients' sera, a significant but low correlation (r ‫؍‬ 0.46) was observed between SBA with rabbit complement (rSBA) using an ST-5 reference strain and SBA with human complement (hSBA) using an ST-7 strain from Ethiopia. While rSBA demonstrated a significant linear relation with IgG against APS, hSBA demonstrated significant linear relationships with IgG against both APS and OMV. This study indicates that antibodies against both outer membrane proteins and APS may be important in providing the protection induced during disease, as measured by hSBA. Therefore, outer membrane proteins could also have a role as components of future meningococcal vaccines for the African meningitis belt.

Characterisation of group A streptococci from necrotising fasciitis cases in Gloucestershire, United Kingdom

Advances in Experimental Medicine and Biology, 1997

... OF GROUP A STREPTOCOCCI FROM NECROTISING FASCIITIS CASES IN GLOUCESTERSHIRE, UNITED KINGDOM A... more

Specificity of subcapsular antibody responses in Ethiopian patients following disease caused by serogroup A meningococci

Clinical and Vaccine …, 2008

The Sexual Cycle and Reproductive Modality in Littorina-Saxatilis Olivi (Mollusca, Gastropoda)

The first large epidemic of meningococcal disease caused by serogroup W135, Burkina Faso, 2002

Vaccine, 2007

In 2001 a significant proportion of cases of meningococcal meningitis toward the end of a serogro... more In 2001 a significant proportion of cases of meningococcal meningitis toward the end of a serogroup A epidemic in Niger and Burkina Faso was found to be caused by serogroup W135 meningococci. The World Health Organization put in place in several African countries an extended surveillance scheme in preparation for a possible epidemic situation. In January 2002, the first large epidemic of meningococcal disease caused by serogroup W135 started in Burkina Faso, resulting in more than 12,000 cases and 1400 deaths. We report here the results of the laboratory-based surveillance and the characteristics of the epidemic clone.

The concept of “tailor-made”, protein-based, outer membrane vesicle vaccines against meningococcal …

Vaccine

Protein-based, outer membrane vesicle (OMV) vaccines have previously proven to be efficacious aga... more

Surveillance of Bacterial Meningitis, Ethiopia, 2012–2013

Emerging Infectious Diseases, 2016

Among 139 patients with suspected bacterial meningitis in Ethiopia, 2012-2013, meningococci (19.4... more Among 139 patients with suspected bacterial meningitis in Ethiopia, 2012-2013, meningococci (19.4%) and pneumococci (12.9%) were the major disease-causing organisms. Meningococcal serogroups detected were A (n = 11), W (n = 7), C (n = 1), and X (n = 1). Affordable, multivalent meningitis vaccines for the African meningitis belt are urgently needed. E thiopia has the second-largest population (≈94 million in 2013) among the meningitis belt countries of sub-Saharan Africa (1). However, during 2001-2010, a median of only 1,056 suspected meningitis cases per year (range 5-8,571/year) was reported to the World Health Organization (2). The largest meningitis epidemics occurred in 1981 (3) and 1989 (4), resulting in ≈45,000 and ≈50,000 cases, respectively. Serogroup A meningococci were the major cause of these epidemics, although serogroup C strains

Public Health Impact After the Introduction of PsA-TT: The First 4 Years

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, Jan 15, 2015

During the first introduction of a group A meningococcal vaccine (PsA-TT) in 2010-2011 and its ro... more During the first introduction of a group A meningococcal vaccine (PsA-TT) in 2010-2011 and its rollout from 2011 to 2013, >150 million eligible people, representing 12 hyperendemic meningitis countries, have been vaccinated. The new vaccine effectiveness evaluation framework was established by the World Health Organization and partners. Meningitis case-based surveillance was strengthened in PsA-TT first-introducer countries, and several evaluation studies were conducted to estimate the vaccination coverage and to measure the impact of vaccine introduction on meningococcal carriage and disease incidence. PsA-TT implementation achieved high vaccination coverage, and results from studies conducted showed significant decrease of disease incidence as well as significant reduction of oropharyngeal carriage of group A meningococci in vaccinated and unvaccinated individuals, demonstrating the vaccine's ability to generate herd protection and prevent group A epidemics. Lessons learned...

Molecular epidemiology of meningococcal disease

Médecine et Maladies Infectieuses, 1991

Factors Contributing to the Persistence of E. coli in the Human Large Intestinal Microflora

Molecular Pathogenesis of Gastrointestinal Infections, 1991

Differentiation of Moraxella nonliquefaciens, M. lacunata, and M. bovis by using multilocus enzyme electrophoresis and hybridization with pilin-specific DNA probes

Journal of clinical microbiology, 1992

Genetic relationships among strains of Moraxella nonliquefaciens, M. lacunata, and M. bovis were ... more Genetic relationships among strains of Moraxella nonliquefaciens, M. lacunata, and M. bovis were studied by using multilocus enzyme electrophoresis and DNA-DNA hybridization. The 74 isolates analyzed for electrophoretic variation at 12 enzyme loci were assigned to 59 multilocus genotypes. The multilocus genotypes were grouped in four major clusters, one representing strains of M. nonliquefaciens, two representing strains of M. lacunata, and one comprising strains of M. bovis and the single strain of M. equi analyzed. DNA-DNA hybridization with total genomic probes also revealed four major distinctive entities that corresponded to those identified by multilocus enzyme electrophoresis. The two distinct clusters recognized among the M. lacunata strains apparently corresponded to the species previously designated M. lacunata and M. liquefaciens. Distinction of the four entities was improved by hybridization with polymerase chain reaction products of nonconserved parts of pilin genes as ...

Epidemiology of invasive meningococcal infections of children in Slovenia during 1993-1999

Central European journal of public health, 2001

Invasive strains of Neisseria meningitidis isolated from sterile body fluids of children aged 0-1... more Invasive strains of Neisseria meningitidis isolated from sterile body fluids of children aged 0-14 years were intentionally collected in nine Slovenian laboratories, and sent to the laboratory of the National Institute of Public Health, Ljubljana for final evaluation. From 1993-1999 we collected 53 invasive strains from children presented in this study. The incidence rate of invasive diseases in children shows that there is a rapid fall from 4.74/100,000 in 1993 to 0.90/100,000 in 1999. Invasive diseases predominated in children in the age group 0-1 year (19.6 cases per 100,000 children); followed by the age groups 2-4 years, 5-9 years and 10-14 years. The results of serogrouping indicate that the largest proportion of meningococci isolated (90%) were group B, while 8% of isolates were group C and only 2% group Y. The serotype/serosubtype distribution shows that the most frequent serotype (excluding 19 non-typable NT strains) was serotype 22, which was expressed in 9 strains and the...

[Tuberculosis in Bergen 1996]

Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 10, 1999

In 1996, 30 patients with tuberculosis were reported from Haukeland University Hospital to the No... more In 1996, 30 patients with tuberculosis were reported from Haukeland University Hospital to the Norwegian Tuberculosis Registry. Culturing proved 63% with mycobacterium tuberculosis (M. tuberculosis). 13 of the patients, eight adults and five children, all natives, were identified as close relatives or friends (cluster). M. tuberculosis with identical restriction fragment length polymorphism pattern (RFLP) were found in all the adults, indicating that they carried the same bacteria strain. We have compared the clinical findings, bacteriology and treatment among the adults in the cluster with other patients with pulmonary tuberculosis identified the same year at the Department of Thoracic Medicine at Haukeland University Hospital. The patients in the cluster were young adults without any previous chest X-ray changes. The other natives with tuberculosis were older, two showing chest X-ray changes indicating former tuberculosis. No difference was seen in sex, BCG status, tuberculin sens...

Meningitis caused by a serogroup W135 clone of the ET-37 complex of Neisseria meningitidis in West Africa

Tropical medicine & international health : TM & IH, 1998

Meningococci belonging to serogroup W135 caused several cases of meningococcal meningitis in The ... more Meningococci belonging to serogroup W135 caused several cases of meningococcal meningitis in The Gambia in 1995 and were isolated during a serogroup A epidemic in Mali in 1994. The eight isolates tested belonged to the same clone of the ET-37 complex and differed in several bands from the pulsed-field gel electrophoresis restriction pattern of serogroup C meningococci of the ET-37 complex isolated in Mali. Three of 6 patients infected in The Gambia died, indicating that this W135 clone is virulent. Vaccines that protect only against infections with meningococci belonging to serogroups A and C are usually used to control outbreaks in Africa, although vaccines containing the W135 polysaccharide are available. The findings of this study indicate that outbreaks of meningococcal meningitis in Africa can be associated with serogroup W135 infections and that serogrouping is essential before vaccination campaigns are started.

Intercontinental spread of a genetically distinctive complex of clones of Neisseria meningitidis causing epidemic disease

Proceedings of the National Academy of Sciences, 1986

Strains of Neisseria meningitidis responsible for an epidemic of meningococcal disease occurring ... more Strains of Neisseria meningitidis responsible for an epidemic of meningococcal disease occurring in Norway since the mid-1970s and for recent increases in the incidence of disease in several other parts of Europe have been identified by multilocus enzyme electrophoresis as members of a distinctive group of 22 closely related clones (the ET-5 complex). Clones of this complex have also colonized South Africa, Chile, Cuba, and Florida, where they have been identified as the causative agents of recent outbreaks of meningococcal disease. There is strong circumstantial evidence that outbreaks of disease occurring in Miami in 1981 and 1982 were caused in large part by bacteria that reached Florida via human immigrants from Cuba.

Seroepidemiological Study after a Long-Distance Industrial Outbreak of Legionnaires' Disease

Clinical and Vaccine Immunology, 2009

Following a long-distance outbreak of Legionnaires' disease from an industrial air scrubber i... more Following a long-distance outbreak of Legionnaires' disease from an industrial air scrubber in Norway in 2005, a seroepidemiological study measuring levels of immunoglobulin G (IgG) and IgM antibodies to Legionella pneumophila was performed with a polyvalent enzyme-linked immunosorbent assay. One year after the outbreak, IgG levels in employees (n = 213) at the industrial plant harboring the scrubber and in blood donors (n = 398) from the outbreak county were low but significantly higher (P ≤ 0.002) than those in blood donors (n = 406) from a nonexposed county. No differences in IgM levels among the three groups were found after adjustment for gender and age. Home addresses of the seroresponders in the exposed county clustered to the city of the outbreak, in contrast to the scattering of addresses of the seroresponding donors in the nonexposed county. Factory employees who operated at an open biological treatment plant had significantly higher IgG and IgM levels (P ≤ 0.034) than...

Genotypic Relationships Among Strains Classified under the (Pasteurella) haemolytica-complex as Indicated by Ribotyping and Multilocus Enzyme Electrophoresis

Zentralblatt für Bakteriologie, 1997

Two-hundred and one strains classified under the (Pasteurella) haemolytica-complex isolated from ... more Two-hundred and one strains classified under the (Pasteurella) haemolytica-complex isolated from cattle, sheep, deer, pigs, hares and rabbits were investigated by ribotyp ing. Fifty-nine of these strains were selected for further studies using multi locus enzyme electrophoresis (MEE). A correlation between the clusters identified by ribotyping and MEE was demonstrated and the results furthermore indicated that a genetic basis ex ists for most clusters previously outlined by the use of quantitative evaluation of phe notypic data. The taxonomic relevance of ornithine decarboxylase and fermentation of L-arabinose, D-sorbitol and glucosides for taxonomic delineation within the (P.) haemolytica-complex was supported. A taxonomic importance was further indicated for ONPG, ONPX, ONPF, meso-inositol, D-xylose, maltose, dextrine and NPG in re lation to some of the taxa. Within the porcine taxon 15, however, differences in orni thine decarboxylase did not correspond to genetic clusters. Six lineages were revealed by MEE. Lineage A contained electrophoretic types (ETs) representing biogroups 1, 3A-3H, 8A and 9, indicating a genetic relationship between these groups-an observation which was supported by ribotyping. Lineage B includ ed biogroup 8D, 3 strains from biogroup 10 and a single strain from biogroup 1 and taxon 18/biovar 1. Lineage C contained strains allocated to biogroup 6 from rumi nants and the porcine taxon 15. The similarity between these two groups was accen tuated by ribotyping. Lineage D and the single isolate in lineage E contained strains al located to biogroups 7, 10, 8B and 8C, in addition to single strains from biogroups 6 334 0. Angen et al. and 9. The same strains were found in the heterogenous ribotype cluster 17. Lineage F contained strains representing the leprine taxon 20 and the ruminant (P.) granulo matis. Ribotyping indicated that the ruminant biogroup 3J was affiliated with both taxon 20 and (P.) granulomatis.

The first large epidemic of meningococcal disease caused by serogroup W135, Burkina Faso, 2002

Vaccine, 2007

In 2001 a significant proportion of cases of meningococcal meningitis toward the end of a serogro... more In 2001 a significant proportion of cases of meningococcal meningitis toward the end of a serogroup A epidemic in Niger and Burkina Faso was found to be caused by serogroup W135 meningococci. The World Health Organization put in place in several African countries an extended surveillance scheme in preparation for a possible epidemic situation. In January 2002, the first large epidemic of meningococcal disease caused by serogroup W135 started in Burkina Faso, resulting in more than 12,000 cases and 1400 deaths. We report here the results of the laboratory-based surveillance and the characteristics of the epidemic clone.

Multilocus sequence typing and ftsI sequencing: a powerful tool for surveillance of penicillin-binding protein 3-mediated beta-lactam resistance in nontypeable Haemophilus influenzae

BMC Microbiology, 2014

Background: Beta-lactam resistance in Haemophilus influenzae due to ftsI mutations causing altere... more Background: Beta-lactam resistance in Haemophilus influenzae due to ftsI mutations causing altered penicillin-binding protein 3 (PBP3) is increasing worldwide. Low-level resistant isolates with the N526K substitution (group II low-rPBP3) predominate in most geographical regions, while high-level resistant isolates with the additional S385T substitution (group III high-rPBP3) are common in Japan and South Korea. Knowledge about the molecular epidemiology of rPBP3 strains is limited. We combined multilocus sequence typing (MLST) and ftsI/PBP3 typing to study the emergence and spread of rPBP3 in nontypeable H. influenzae (NTHi) in Norway. Results: The prevalence of rPBP3 in a population of 795 eye, ear and respiratory isolates (99% NTHi) from 2007 was 15%. The prevalence of clinical PBP3-mediated resistance to ampicillin was 9%, compared to 2.5% three years earlier. Group II low-rPBP3 predominated (96%), with significant proportions of isolates non-susceptible to cefotaxime (6%) and meropenem (20%). Group III high-rPBP3 was identified for the first time in Northern Europe. Four MLST sequence types (ST) with characteristic, highly diverging ftsI alleles accounted for 61% of the rPBP3 isolates. The most prevalent substitution pattern (PBP3 type A) was present in 41% of rPBP3 isolates, mainly carried by ST367 and ST14. Several unrelated STs possessed identical copies of the ftsI allele encoding PBP3 type A. Infection sites, age groups, hospitalization rates and rPBP3 frequencies differed between STs and phylogenetic groups. Conclusions: This study is the first to link ftsI alleles to STs in H. influenzae. The results indicate that horizontal gene transfer contributes to the emergence of rPBP3 by phylogeny restricted transformation. Clonally related virulent rPBP3 strains are widely disseminated and high-level resistant isolates emerge in new geographical regions, threatening current empiric antibiotic treatment. The need of continuous monitoring of beta-lactam susceptibility and a global system for molecular surveillance of rPBP3 strains is underlined. Combining MLST and ftsI/PBP3 typing is a powerful tool for this purpose.

Clonal analysis of Escherichia coli O2:K1 isolated from diseased humans and animals

Infection and Immunity, 1986

Forty-six Escherichia coli isolates of serotype O2:K1 from human urinary tract infections, chicke... more Forty-six Escherichia coli isolates of serotype O2:K1 from human urinary tract infections, chicken sepsis, and bovine mastitis were obtained from laboratories in England, Denmark, Sweden, and Finland. The bacteria were compared for outer membrane protein (OMP) pattern, lipopolysaccharide pattern, electrophoretic mobilities of enzymes, and flagellar serotype and were tested for fimbriation, biotype, hydroxamate production, hemolysin production, antibiotic resistance, plasmid content, colicin production, and virulence in neonatal rats. Isolates from humans were assigned to two clonal groups; poultry isolates belonged to one of these clonal groups, whereas bovine isolates belonged to the other. Poultry and human isolates of the same clonal group could be distinguished only by their plasmid content. Strains within this group were heterogeneous with respect to biotype, fimbriation, virulence, and flagellar serotype. Human and bovine isolates of the second clonal group were distinguished ...

Serum antibody responses in Ethiopian meningitis patients infected with Neisseria meningitidis serogroup A sequence type 7

Clinical and Vaccine …, 2007

To elucidate critical components of protective immune responses induced during the natural course... more To elucidate critical components of protective immune responses induced during the natural course of serogroup A meningococcal disease, we studied acute-, early-convalescent-, and late-convalescent-phase sera from Ethiopian patients during outbreaks in 2002 to 2003. Sera were obtained from laboratory-confirmed patients positive for serogroup A sequence type 7 (ST-7) meningococci (A:4/21:P1.20,9) (n ‫؍‬ 71) and from Ethiopian controls (n ‫؍‬ 113). The sera were analyzed using an enzyme-linked immunosorbent assay to measure levels of immunoglobulin G (IgG) against serogroup A polysaccharide (APS) and outer membrane vesicles (OMVs) and for serum bactericidal activity (SBA) using both rabbit and human complement sources. Despite relatively high SBA titers and high levels of IgG against APS and OMVs in acute-phase patient sera, significant increases were seen in the early convalescent phase. Antibody concentrations returned to acutephase levels in the late convalescent phase. Considering all patients' sera, a significant but low correlation (r ‫؍‬ 0.46) was observed between SBA with rabbit complement (rSBA) using an ST-5 reference strain and SBA with human complement (hSBA) using an ST-7 strain from Ethiopia. While rSBA demonstrated a significant linear relation with IgG against APS, hSBA demonstrated significant linear relationships with IgG against both APS and OMV. This study indicates that antibodies against both outer membrane proteins and APS may be important in providing the protection induced during disease, as measured by hSBA. Therefore, outer membrane proteins could also have a role as components of future meningococcal vaccines for the African meningitis belt.

Characterisation of group A streptococci from necrotising fasciitis cases in Gloucestershire, United Kingdom

Advances in Experimental Medicine and Biology, 1997

... OF GROUP A STREPTOCOCCI FROM NECROTISING FASCIITIS CASES IN GLOUCESTERSHIRE, UNITED KINGDOM A... more

Specificity of subcapsular antibody responses in Ethiopian patients following disease caused by serogroup A meningococci

Clinical and Vaccine …, 2008

The Sexual Cycle and Reproductive Modality in Littorina-Saxatilis Olivi (Mollusca, Gastropoda)

The first large epidemic of meningococcal disease caused by serogroup W135, Burkina Faso, 2002

Vaccine, 2007

In 2001 a significant proportion of cases of meningococcal meningitis toward the end of a serogro... more In 2001 a significant proportion of cases of meningococcal meningitis toward the end of a serogroup A epidemic in Niger and Burkina Faso was found to be caused by serogroup W135 meningococci. The World Health Organization put in place in several African countries an extended surveillance scheme in preparation for a possible epidemic situation. In January 2002, the first large epidemic of meningococcal disease caused by serogroup W135 started in Burkina Faso, resulting in more than 12,000 cases and 1400 deaths. We report here the results of the laboratory-based surveillance and the characteristics of the epidemic clone.

The concept of “tailor-made”, protein-based, outer membrane vesicle vaccines against meningococcal …

Vaccine

Protein-based, outer membrane vesicle (OMV) vaccines have previously proven to be efficacious aga... more

Surveillance of Bacterial Meningitis, Ethiopia, 2012–2013

Emerging Infectious Diseases, 2016

Among 139 patients with suspected bacterial meningitis in Ethiopia, 2012-2013, meningococci (19.4... more Among 139 patients with suspected bacterial meningitis in Ethiopia, 2012-2013, meningococci (19.4%) and pneumococci (12.9%) were the major disease-causing organisms. Meningococcal serogroups detected were A (n = 11), W (n = 7), C (n = 1), and X (n = 1). Affordable, multivalent meningitis vaccines for the African meningitis belt are urgently needed. E thiopia has the second-largest population (≈94 million in 2013) among the meningitis belt countries of sub-Saharan Africa (1). However, during 2001-2010, a median of only 1,056 suspected meningitis cases per year (range 5-8,571/year) was reported to the World Health Organization (2). The largest meningitis epidemics occurred in 1981 (3) and 1989 (4), resulting in ≈45,000 and ≈50,000 cases, respectively. Serogroup A meningococci were the major cause of these epidemics, although serogroup C strains

Public Health Impact After the Introduction of PsA-TT: The First 4 Years

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, Jan 15, 2015

During the first introduction of a group A meningococcal vaccine (PsA-TT) in 2010-2011 and its ro... more During the first introduction of a group A meningococcal vaccine (PsA-TT) in 2010-2011 and its rollout from 2011 to 2013, >150 million eligible people, representing 12 hyperendemic meningitis countries, have been vaccinated. The new vaccine effectiveness evaluation framework was established by the World Health Organization and partners. Meningitis case-based surveillance was strengthened in PsA-TT first-introducer countries, and several evaluation studies were conducted to estimate the vaccination coverage and to measure the impact of vaccine introduction on meningococcal carriage and disease incidence. PsA-TT implementation achieved high vaccination coverage, and results from studies conducted showed significant decrease of disease incidence as well as significant reduction of oropharyngeal carriage of group A meningococci in vaccinated and unvaccinated individuals, demonstrating the vaccine's ability to generate herd protection and prevent group A epidemics. Lessons learned...

Molecular epidemiology of meningococcal disease

Médecine et Maladies Infectieuses, 1991

Factors Contributing to the Persistence of E. coli in the Human Large Intestinal Microflora

Molecular Pathogenesis of Gastrointestinal Infections, 1991

Differentiation of Moraxella nonliquefaciens, M. lacunata, and M. bovis by using multilocus enzyme electrophoresis and hybridization with pilin-specific DNA probes

Journal of clinical microbiology, 1992

Genetic relationships among strains of Moraxella nonliquefaciens, M. lacunata, and M. bovis were ... more Genetic relationships among strains of Moraxella nonliquefaciens, M. lacunata, and M. bovis were studied by using multilocus enzyme electrophoresis and DNA-DNA hybridization. The 74 isolates analyzed for electrophoretic variation at 12 enzyme loci were assigned to 59 multilocus genotypes. The multilocus genotypes were grouped in four major clusters, one representing strains of M. nonliquefaciens, two representing strains of M. lacunata, and one comprising strains of M. bovis and the single strain of M. equi analyzed. DNA-DNA hybridization with total genomic probes also revealed four major distinctive entities that corresponded to those identified by multilocus enzyme electrophoresis. The two distinct clusters recognized among the M. lacunata strains apparently corresponded to the species previously designated M. lacunata and M. liquefaciens. Distinction of the four entities was improved by hybridization with polymerase chain reaction products of nonconserved parts of pilin genes as ...

Epidemiology of invasive meningococcal infections of children in Slovenia during 1993-1999

Central European journal of public health, 2001

Invasive strains of Neisseria meningitidis isolated from sterile body fluids of children aged 0-1... more Invasive strains of Neisseria meningitidis isolated from sterile body fluids of children aged 0-14 years were intentionally collected in nine Slovenian laboratories, and sent to the laboratory of the National Institute of Public Health, Ljubljana for final evaluation. From 1993-1999 we collected 53 invasive strains from children presented in this study. The incidence rate of invasive diseases in children shows that there is a rapid fall from 4.74/100,000 in 1993 to 0.90/100,000 in 1999. Invasive diseases predominated in children in the age group 0-1 year (19.6 cases per 100,000 children); followed by the age groups 2-4 years, 5-9 years and 10-14 years. The results of serogrouping indicate that the largest proportion of meningococci isolated (90%) were group B, while 8% of isolates were group C and only 2% group Y. The serotype/serosubtype distribution shows that the most frequent serotype (excluding 19 non-typable NT strains) was serotype 22, which was expressed in 9 strains and the...

[Tuberculosis in Bergen 1996]

Tidsskrift for den Norske lægeforening : tidsskrift for praktisk medicin, ny række, Jan 10, 1999

In 1996, 30 patients with tuberculosis were reported from Haukeland University Hospital to the No... more In 1996, 30 patients with tuberculosis were reported from Haukeland University Hospital to the Norwegian Tuberculosis Registry. Culturing proved 63% with mycobacterium tuberculosis (M. tuberculosis). 13 of the patients, eight adults and five children, all natives, were identified as close relatives or friends (cluster). M. tuberculosis with identical restriction fragment length polymorphism pattern (RFLP) were found in all the adults, indicating that they carried the same bacteria strain. We have compared the clinical findings, bacteriology and treatment among the adults in the cluster with other patients with pulmonary tuberculosis identified the same year at the Department of Thoracic Medicine at Haukeland University Hospital. The patients in the cluster were young adults without any previous chest X-ray changes. The other natives with tuberculosis were older, two showing chest X-ray changes indicating former tuberculosis. No difference was seen in sex, BCG status, tuberculin sens...

Meningitis caused by a serogroup W135 clone of the ET-37 complex of Neisseria meningitidis in West Africa

Tropical medicine & international health : TM & IH, 1998

Meningococci belonging to serogroup W135 caused several cases of meningococcal meningitis in The ... more Meningococci belonging to serogroup W135 caused several cases of meningococcal meningitis in The Gambia in 1995 and were isolated during a serogroup A epidemic in Mali in 1994. The eight isolates tested belonged to the same clone of the ET-37 complex and differed in several bands from the pulsed-field gel electrophoresis restriction pattern of serogroup C meningococci of the ET-37 complex isolated in Mali. Three of 6 patients infected in The Gambia died, indicating that this W135 clone is virulent. Vaccines that protect only against infections with meningococci belonging to serogroups A and C are usually used to control outbreaks in Africa, although vaccines containing the W135 polysaccharide are available. The findings of this study indicate that outbreaks of meningococcal meningitis in Africa can be associated with serogroup W135 infections and that serogrouping is essential before vaccination campaigns are started.

Intercontinental spread of a genetically distinctive complex of clones of Neisseria meningitidis causing epidemic disease

Proceedings of the National Academy of Sciences, 1986

Strains of Neisseria meningitidis responsible for an epidemic of meningococcal disease occurring ... more Strains of Neisseria meningitidis responsible for an epidemic of meningococcal disease occurring in Norway since the mid-1970s and for recent increases in the incidence of disease in several other parts of Europe have been identified by multilocus enzyme electrophoresis as members of a distinctive group of 22 closely related clones (the ET-5 complex). Clones of this complex have also colonized South Africa, Chile, Cuba, and Florida, where they have been identified as the causative agents of recent outbreaks of meningococcal disease. There is strong circumstantial evidence that outbreaks of disease occurring in Miami in 1981 and 1982 were caused in large part by bacteria that reached Florida via human immigrants from Cuba.