RESUMO
Serotype 3 is one of the most often detected pneumococcal serotypes in adults and it is associated with serious disease. In contrast, the isolation of serotype 3 by bacterial culture is unusual in children with invasive pneumococcal disease (IPD). The purpose of this study was to learn the serotype distribution of IPD, including culture-negative episodes, by using molecular methods in normal sterile samples. We studied all children<5 years of age with IPD admitted to two paediatric hospitals in Catalonia, Spain, from 2007 to 2009. A sequential real-time polymerase chain reaction (PCR) approach was added to routine methods for the detection and serotyping of pneumococcal infection. Among 257 episodes (219 pneumonia, 27 meningitis, six bacteraemia and five others), 33.5% were identified by culture and the rest, 66.5%, were detected exclusively by real-time PCR. The most common serotypes detected by culture were serotypes 1 (26.7%) and 19A (25.6%), and by real-time PCR, serotypes 1 (19.8%) and 3 (18.1%). Theoretical coverage rates by the PCV7, PCV10 and PCV13 vaccines were 10.5, 52.3 and 87.2%, respectively, for those episodes identified by culture, compared to 5.3, 31.6 and 60.2% for those identified only by real-time PCR. Multiplex real-time PCR has been shown to be useful for surveillance studies of IPD. Serotype 3 is underdiagnosed by culture and is important in paediatric IPD.
Assuntos
Técnicas Bacteriológicas/métodos , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/isolamento & purificação , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Prevalência , Sorotipagem , Espanha/epidemiologia , Streptococcus pneumoniae/genéticaRESUMO
To evaluate compliance with preparedness plans, actors simulating avian influenza attended various hospital emergency departments and public health centres during the last quarter of 2007. Most centres (89%) did not respond correctly. The useful information obtained was sent to the medical and administrative staff who were responsible for the preparedness plans. Awareness of these errors and their rectification can lead to improvements in the response to any case of influenza with pandemic potential and in the capacity to combat any other emergent or re-emergent community infection.
Assuntos
Defesa Civil/métodos , Controle de Doenças Transmissíveis/métodos , Pesquisa sobre Serviços de Saúde , Influenza Humana/diagnóstico , Influenza Humana/terapia , Pandemias/prevenção & controle , Simulação de Paciente , Adulto , Feminino , Humanos , MasculinoRESUMO
Cat scratch disease (CSD), bacillary angiomatosis, hepatic peliosis and some cases of bacteraemia, endocarditis, and osteomyelitis are directly caused by some species of the genus Bartonella. The purpose of this study was to determine the prevalence of IgG antibodies against Bartonella henselae in healthy people and to identify the epidemiological factors involved. Serum samples from 218 patients were examined by indirect immunofluorescence assay (IFA). Significance levels for univariate statistical analysis were determined by the Mann-Whitney U test, chi2 test and Fisher's exact test. Of 218 patients, 99 were female and 119 male, with a median age of 34.36 years (range 0-91 years). Nineteen (8.7%) reacted with B. henselae antigens. Of all the factors concerning the seroprevalence rate being studied (age, sex, contact with animals, residential area), only age was statistically significant. Our serological data seems to indicate that B. henselae is present in Catalonia and could be transmitted to humans.
Assuntos
Angiomatose Bacilar/epidemiologia , Anticorpos Antibacterianos/sangue , Bartonella henselae/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiomatose Bacilar/imunologia , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Soroepidemiológicos , Espanha/epidemiologia , Adulto JovemRESUMO
AIMS: To analyze the prevalence of hepatitis B virus infection markers and hepatitis B vaccination in a representative sample of the juvenile and adult population of Catalonia and to evaluate the changes with respect to seroepidemiological surveys carried out in 1989 and 1996. DESIGN: In all subjects anti-HBc and anti-HBs antibodies and HBsAg were determined using an ELISA test. The possible association between sociodemographic variables and the prevalence of markers was analysed by calculating the adjusted odd ratio (simple logistic regression). SETTING: The study was carried out in 2002 in representative samples of the juvenile (5-14 years) and adult population (>or= 15 years) of Catalonia (Spain). MAIN RESULTS: In 2002 the global prevalence of HBsAg+ was 0.7% (95% CI: 0.4-1.0) and that of anti-HBc+ 8.7% (95% CI: 7.6-9.8), values higher than those obtained in 1989 of 1.5% (95% CI: 1.0-2.1) and 15.6 (95% CI: 13.9-17.3). The prevalence of markers of infection increased with age. The only sociodemographic variable significantly associated with the prevalence of hepatitis B virus infection was the place of birth. The risk of infection was twice as high in subjects born outside Catalonia (p<0.01), adjusted OR 2.0 (95% CI: 1.34-2.98) compared with those born in Catalonia. CONCLUSIONS: The results of this study show that the prevalence of hepatitis B virus infection (anti-HBc+) in Catalonia (Spain) is currently the lowest it has ever been and suggest that there has been a change in the pattern of endemicity of hepatitis B virus infection in Catalonia, which has become a country of low endemicity.
Assuntos
Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Soroepidemiológicos , Espanha/epidemiologiaRESUMO
Vaccination coverage in a representative sample of children under 3 years of age in Catalonia (Spain) was studied. Parents of children selected were contacted and asked for the child's vaccination card. A total of 630 children were included, of whom 570 were indigenous and 60 immigrants. Primary vaccination coverage was 96.5% for indigenous and 85% for immigrant children (p=0.0001), while the coverage of primary vaccination plus booster doses was 88.6% in indigenous and 78.3% in immigrant children (p=0.02). Efforts should be made to increase primary vaccination coverage in immigrant children and booster dose coverage in both indigenous and immigrant children.
Assuntos
Emigração e Imigração , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Programas de Imunização/estatística & dados numéricos , Vacinação/estatística & dados numéricos , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Estudos Retrospectivos , EspanhaRESUMO
Titres of anti-tetanus toxin antibodies > or = 0.1 IU/ml were determined using an enzyme linked immunosorbent assay in representative samples of the juvenile and adult population of Catalonia. The prevalence obtained in 1,316 juveniles and 1,296 adults was 99.4 and 68.3%, respectively. In adults, the prevalence in males (76.5%) was higher (P < 0.001) than in females (61.7%), fell with increasing age and was higher in subjects born in Catalonia (72.5%) than in those born outside Catalonia (57.9%) (P < 0.001). These results show that routine vaccination of children is successful. In adults aged > or = 45 years, the prevalence is inadequate and efforts should be made to increase vaccination.
Assuntos
Antitoxina Tetânica/sangue , Tétano/epidemiologia , Tétano/microbiologia , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Clostridium tetani/metabolismo , Clostridium tetani/patogenicidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Soroepidemiológicos , Espanha/epidemiologia , Tétano/metabolismo , Antitoxina Tetânica/imunologia , VacinaçãoRESUMO
Rickettsia slovaca, the causative agent of TIBOLA, is transmitted by Dermacentor ticks. Dermacentor marginatus is the most widely species distributed in northeastern Spain, and the wild boar constitutes the main host. D. marginatus ticks were collected from hunter-killed wild boar and were tested by PCR/RFLP. Rickettsial DNA-positive ticks were sequenced using the ompA PCR primers. The prevalence of R. slovaca in D. marginatus ticks was 17.7%. Other spotted fever group rickettsiae were detected in ticks, but these were not definitely identified.
Assuntos
Dermacentor/microbiologia , Rickettsia/classificação , Suínos/microbiologia , Animais , Feminino , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Rickettsia/genética , Rickettsia/isolamento & purificação , EspanhaAssuntos
Infecções por Rickettsia/diagnóstico , Rickettsia/isolamento & purificação , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Testes Sorológicos , EspanhaRESUMO
Rickettsia typhi and Rickettsia conorii, the etiologic agents of, respectively, murine typhus and Mediterranean spotted fever, are recognized as frequent causes of fever of intermediate duration in southern Spain; in addition, in recent years Rickettsia felis has been detected in potential vectors in this area. Nevertheless, limited data exist regarding the actual prevalence of past infection due to these three pathogens. In the present study, the prevalence of past infection due to R. felis, R. typhi, and R. conorii was determined in a representative population of southern Spain during 2002. In addition, the possible risk factors associated with exposure to these pathogens were investigated. An epidemiological survey was completed by all subjects included in the study. Serum samples were tested by indirect immunofluorescence assay. The prevalence of past infection due to R. felis, R. typhi, and R. conorii among the 504 total subjects was 6.5, 3.8 and 8.7%, respectively. In multivariate analysis, infection due to R. felis was independently associated with a high-risk occupation (one that required working outdoors in nature, close contact with domestic animals, or potential contact with rodents) (OR=5.8; 95%CI 2.1-15.6), while infection due to R. typhi was associated with older age (factor of 1.04 [95%CI 1.008-1.068]) and frequent insect bites (OR=10.3; 95%CI 2.3-45.5). Two factors were associated with infection due to R. conorii: a high-risk occupation (OR=9.3; 95%CI 3.7-23.2), and participation in outdoor activities (OR=7.2; 95%CI 1.4-38.5). The results confirm the widespread prevalence of past infection due to R. felis, R. typhi, and R. conorii in the population of southern Spain.
Assuntos
Febre Botonosa/epidemiologia , Infecções por Rickettsia/epidemiologia , Tifo Endêmico Transmitido por Pulgas/epidemiologia , Adolescente , Adulto , Idoso , Análise de Variância , Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Rickettsia conorii , Rickettsia felis , Rickettsia typhi , Fatores de Risco , Estudos Soroepidemiológicos , Espanha/epidemiologiaRESUMO
Determination of antibody levels against vaccine-preventable diseases is of great value to assess immunization programmes. The objective of this study was to determine the prevalence of measles, rubella, and mumps antibodies in representative samples of the child and adult population of Catalonia and compare the findings to those obtained in 1996. A representative sample of the child and adult (>or=15 years) population of Catalonia was studied. Enzyme-linked immunosorbent assay techniques were used to determine the presence of antibodies. Equivocal results for antibodies against measles and rubella were tested using an immunofluorescence technique. To compare proportions, the chi-square test and the Fisher's exact test were used. Statistical significance was set at 0.05. Adjusted odds ratios were calculated using multiple logistic regression analysis. Samples from 2,619 people were analyzed. The global prevalence of antibodies was 98.3% for measles, 91.1% for mumps, and 98.1% for rubella. The prevalence of rubella antibodies was higher in women than in men (98.8 vs. 97.2%, respectively). Compared with the results obtained in the 1996 seroprevalence study, only the prevalence of rubella antibodies showed a statistically significant increase in men (97.2 vs. 94.6%; p=0.002) and, in particular, in women (98.8 vs. 95.3%; p<0.001). The low prevalence of susceptible subjects has already led to the elimination of indigenous measles in Catalonia and should allow the elimination of indigenous rubella by 2005. The level of antibodies necessary to interrupt the transmission of mumps has still not been reached in all age groups.
Assuntos
Sarampo/sangue , Sarampo/epidemiologia , Caxumba/epidemiologia , Rubéola (Sarampo Alemão)/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos/sangue , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Sarampo/virologia , Pessoa de Meia-Idade , Caxumba/sangue , Caxumba/virologia , Rubéola (Sarampo Alemão)/sangue , Rubéola (Sarampo Alemão)/virologia , Estudos Soroepidemiológicos , Espanha/epidemiologiaRESUMO
The prevalence of past infections due to Bar29 rickettsial strain in a population from Southern Europe, as well as the possible risk factors associated to exposure to this rickettsia, were analysed. Among the 504 subjects included, global prevalence of past infections was 3.4%. Past infections were significantly more frequent in rural areas compared to urban (10.8 vs. 3.2%, OR 3.6 [1.1-12.3], P = .05), and suburban areas (10.8 vs. 1.9%, OR 6.2 [1.3-28.9], P = .02). In multivariate analysis the factors that were independently associated to past infection due to Bar29 strain were higher age (P = .037; factor of 1.033 [1.002-1.066]), and a risk profession (P = .005; OR = 5.7 [1.6-19.6]). These data point towards the presence of past Bar29 strain infections in a population from Southern Spain.
Assuntos
Infecções por Rickettsia/epidemiologia , Rickettsia/isolamento & purificação , Rickettsia/patogenicidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Animais , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina G/sangue , Lactente , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Prevalência , Rickettsia/imunologia , Infecções por Rickettsia/imunologia , Infecções por Rickettsia/microbiologia , Fatores de Risco , Espanha/epidemiologiaRESUMO
The aim of the study was to describe the impact of hepatitis B vaccination and disease incidence in adolescents and young people 12 years after the launching of a mass hepatitis B vaccination of pre-adolescents in schools. Vaccination coverage was assessed using administrative and serological data. Infection trends were evaluated by means of seroepidemiological surveys. High levels of vaccination coverage and vaccine-induced immunity were achieved. The resulting low proportions of susceptible adolescents and young people have undoubtedly contributed to the substantial reduction in the prevalence of hepatitis B infection in the 15-24 years age group (0.9 per 100 in 2001 versus 9.3 per 100 in 1986) and in the reported incidence of hepatitis B cases (80% reduction). Over the last 3 years, the declining trend seems to have been halted, although 35% of cases reported during this period corresponded to immigrants.
Assuntos
Vacinas contra Hepatite B/farmacologia , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Instituições Acadêmicas , Estudos Soroepidemiológicos , Espanha/epidemiologia , Fatores de TempoRESUMO
Norovirus infection is associated with approximately 90% of epidemic non-bacterial acute gastroenteritis. The objective of this study is to describe an outbreak of norovirus genogroup I gastroenteritis which affected workers in a hospital and was attributed to food prepared by an infected food handler. Forty cases were detected, of whom 80% were interviewed. The index case was the cook employed in the hospital cafeteria. The following symptoms were observed: abdominal pain in 90.6%, vomiting in 71.9%, diarrhoea in 71.9%, general indisposition in 62.5%, headaches in 53.1% and fever in 32.4% of cases. The initial symptoms were abdominal pain in 37% and vomiting in 28%. Of the 14 samples analysed by RT-PCR, 12 (86%) were positive for a genogroup I norovirus. After sequencing the strain was identified as genotype Desert Shield. Many of the foodstuffs consumed were made by hand, favouring transmission from the index case to the cafeteria users.
Assuntos
Infecções por Caliciviridae/epidemiologia , Surtos de Doenças , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Norovirus/genética , Adulto , Feminino , Contaminação de Alimentos , Manipulação de Alimentos , Genótipo , Humanos , Masculino , Espanha/epidemiologiaAssuntos
Antibacterianos/farmacologia , Infecções Meningocócicas/microbiologia , Neisseria meningitidis/efeitos dos fármacos , Farmacorresistência Bacteriana , Características da Família , Humanos , Infecções Meningocócicas/tratamento farmacológico , Testes de Sensibilidade Microbiana , Neisseria meningitidis/classificação , Sorotipagem , Fatores de TempoRESUMO
During the fourth quarter of 1997, a vaccination campaign using the meningococcal C polysaccharide vaccine was carried out in 14 autonomous regions of Spain. The remaining three regions did not participate. In the last quarter of the year 2000, a mass vaccination campaign using the meningococcal C conjugated vaccine was carried out in all regions. In the year 2001 the incidence decreased in all regions, although the decrease was greater in regions that did not vaccinate in 1997. In contrast, case fatality rates did not decrease. During 2001, the incidence rate of meningococcal C disease was still lower (0.32 per 100000 persons-year) in the regions that vaccinated in 1997 with the polysaccharide vaccine than in those that did not (0.64 per 100000 persons-year).
Assuntos
Vacinação em Massa/estatística & dados numéricos , Meningite Meningocócica/prevenção & controle , Vacinas Meningocócicas , Neisseria meningitidis Sorogrupo C/imunologia , Polissacarídeos/química , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Lactente , Meningite Meningocócica/epidemiologia , Meningite Meningocócica/mortalidade , Vacinas Meningocócicas/química , Vigilância da População , Espanha/epidemiologia , Vacinas Conjugadas/químicaRESUMO
In the last quarter of the year 2000, the meningococcal C conjugated vaccine was incorporated into the routine vaccination schedule in Catalonia (at 2, 4 and 6 months). In addition a vaccination campaign was carried out in children <6 years of age, with a coverage of 96.2%. The effectiveness of the vaccination in this age group during 2001 and the first 28 weeks of 2002 was 100% (94.27-100%). A vaccination campaign has been carried out in 6-19-year olds during 2001 and 2002, with a coverage rate of 23.5% in the year 2001. In this age group a reduction in disease incidence was seen in the 2000-2001 season, but not in the following one.
Assuntos
Vacinação em Massa/estatística & dados numéricos , Meningite Meningocócica/epidemiologia , Vacinas Meningocócicas , Neisseria meningitidis Sorogrupo C/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Humanos , Esquemas de Imunização , Lactente , Vacinas Meningocócicas/administração & dosagem , Saúde Pública , Espanha/epidemiologia , Vacinas Conjugadas/administração & dosagemRESUMO
BACKGROUND: The aim of this study was to investigate the clinical and epidemiological characteristics of meningococcal disease in Catalonia (Spain) after vaccination with the polysaccharide vaccine. PATIENTS AND METHODS: Cases were collected by the Statutory Diseases Reporting System. RESULTS: 176 cases were reported, an overall incidence of 2.9/100,000 persons/year. 60% of cases occurred during winter and spring. The case fatality rate was 6.3%. The highest age incidence was in children under 2 years of age (48/100,000 persons/year). Comparison of the cases detected by the Statutory Diseases Reporting System with those obtained by the Microbiological Reporting System shows that meningococcal disease surveillance in Catalonia was relatively complete (95.7%), with a positive predictive value of 66.3%. 115 cases (65%) were culture-confirmed with a rate of 1.9/100,000 persons/year. 86 (75%) cases were due to Neisseria meningitidis serogroup B and 21 to serogroup C (18%). CONCLUSION: Although infections due to serogroup C have decreased after mass vaccination with the polysaccharide vaccine, it is likely that the number of infections will decrease further with the conjugate meningococcal group C vaccine.
Assuntos
Vacinação em Massa , Infecções Meningocócicas/epidemiologia , Infecções Meningocócicas/prevenção & controle , Polissacarídeos Bacterianos/administração & dosagem , Adolescente , Adulto , Distribuição por Idade , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Programas de Imunização , Lactente , Masculino , Meningite Meningocócica/diagnóstico , Meningite Meningocócica/epidemiologia , Meningite Meningocócica/prevenção & controle , Infecções Meningocócicas/diagnóstico , Vacinas Meningocócicas/administração & dosagem , Pessoa de Meia-Idade , Prevalência , Sistema de Registros , Medição de Risco , Testes Sorológicos , Distribuição por Sexo , Espanha/epidemiologia , Taxa de Sobrevida , Fatores de TempoRESUMO
The aim of this study was to investigate the incidence of invasive pneumococcal disease (IPD) in Catalonia. A hospital-based incidence study of the period 1997-1999 was carried out by reviewing the isolations of Streptococcus pneumoniae obtained from normally sterile sites reported by the hospitals that voluntarily participate in the Microbiological Reporting System of Catalonia (MRSC), and those obtained by active retrospective surveillance of cases recorded by microbiology laboratories of the remaining hospitals. Cases of pneumonia were included only if the blood culture was positive. The age, sex and clinical presentation of each patient were recorded. The global incidence of hospital-based IPD was 10.5 per 100,000 persons-year, and was much higher in subjects <2 years of age (59.6) and in those aged > or = 65 years (27.9). In subjects > or = 65 years, bacteremic pneumococcal pneumonias were more frequent in the months from December to March than they were in children <2 years of age (P<0.0001). The global incidence of IPD (10.5 per 100,000 persons-year) is high in Catalonia, greater than that of meningococcal or Haemophilus influenzae invasive disease. In children <2 years, the incidence is nearly six times higher (59.6 per 100,000 persons-year) with pneumonias (rate of 26.2 per 100,000 persons-year) and non-focal bacteremias (rate of 22.1 per 100,000 persons-year) being especially frequent.
Assuntos
Infecções Pneumocócicas/epidemiologia , Adolescente , Adulto , Idoso , Bacteriemia/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Laboratórios Hospitalares , Masculino , Meningite Pneumocócica/epidemiologia , Pessoa de Meia-Idade , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/farmacologia , Pneumonia Pneumocócica/epidemiologia , Regionalização da Saúde , Espanha/epidemiologia , Streptococcus pneumoniae/isolamento & purificaçãoRESUMO
The aim of this study was to determine the prevalence of healthy Neisseria meningitidis pharyngeal carriers in a representative sample of the Catalonian school population, as well as its associated factors. The sample was divided into age groups: < or = 5, 6-7 and 13-14 years old. Parents were given a questionnaire to collect information on sociodemographic and epidemiological variables. Oropharyngeal swabs were collected with a cotton-tipped swab in an Amies transport medium and cultured on Thayer Martin plates at 35 degrees C in 5% CO2. The isolates were serogrouped and sero/subtyped. Of the 1406 children studied, 75 (5.34%) meningococcal carriers were detected: 63 B (4.5%), 9 non groupable (0.7%), 2 29E (0.1%) and 1X (0.07%). No serogroup C meningococci were found in this study, probably due to the high A+C vaccination coverage of up to 68.9% in children 6-7 years old. Bivariate analysis identified six statistically significant risk factors for meningococcal carriage: increasing age, recent upper respiratory tract infection, previous antibiotic treatment, number of students in the class, size of the classroom and social class. Multivariate analysis found that only age and previous antibiotic treatment remained statistically significant when the other factors were controlled.
Assuntos
Portador Sadio/epidemiologia , Infecções Meningocócicas/epidemiologia , Neisseria meningitidis/isolamento & purificação , Adolescente , Distribuição por Idade , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Prevalência , Espanha/epidemiologia , Inquéritos e QuestionáriosRESUMO
A population-based study was carried out in Catalonia (Spain) from May 1998 to April 1999 to determine the prevalence of Neisseria meningitidis strains in meningococcal disease (MD) cases and their contacts, as well as the prevalence of meningococci in close contacts of patients with MD, and risk factors for its carriage. A total of 364 close contacts of 87 patients with MD were studied. Throat samples were collected by hospital staff before rifampicin chemoprophylaxis was begun. For each contact, a questionnaire was completed for sociodemographic and epidemiological data. A total of 61 contacts (an overall prevalence of 16.8%) were carriers of meningococcal strains (40 B, 10 C, 1 Z and 10 non-groupable isolates). This prevalence is two to three times higher than in the general population (5-10%). In 33/61 microbiologically confirmed cases (54%) and in 9/26 probable cases (35%), contacts carrying N. meningitidis were found. In 22/33 confirmed cases with carrier contacts, it was possible to study the phenotype of the carrier and patient strains (sero-group, serotype and serosubtype). In 14 cases (64%), both strains were identical, in four cases, only a minor change was observed, in three cases, some strain (from the case or from his contact) was non-serotypable and non-serosubtypable, and in one case, both isolates were completely different. Bivariate analysis identified five statistically significant risk factors for meningococcal carriage: age (5-9 years old), meningococcal A+C vaccination, severe household overcrowding, social class and heavy active smoking (>20 cigarettes a day). Multivariate analysis revealed that of these five variables, only heavy active smoking remained statistically significant when the other factors were controlled.