Parental smoking and carriage of Neisseria meningitidis among Greek schoolchildren

A Case-Control Study on the Risk Factors for Meningococcal Disease among Children in Greece

Purpose

The aim of this study was to identify environmental or genetic risk factors that are associated with invasive meningococcal disease (IMD) in children in Greece.

Methods

A case-control study was performed in 133 children (44 cases and 89 controls) aged between 0–14 years, who were hospitalized in a children's hospital in Athens. Demographics and possible risk factors were collected by the use of a structured questionnaire. To investigate the association of mannose binding lectin (MBL) with IMD, a frequency analysis of the haplotypes of the MBL2 gene and quantitative measurement of MBL serum protein levels were performed using Nanogen NanoChipR 400 technology and immuno-enzyme techniques, respectively.

Results

The multivariate analysis revealed that changes in a child's life setting (relocation or vacation, OR = 7.16), paternal smoking (OR = 4.51), upper respiratory tract infection within the previous month (OR = 3.04) and the density of people in the house/100m² (OR = 3.16), were independent risk factors associated with IMD. Overall 18.8% of patients had a MBL2 genotype with low functionality compared to 10.1% of healthy controls, but this was not statistically significant (p = 0.189).

Conclusion

Prevention strategies aimed at reducing parental smoking and other risk factors identified in this study could decrease the risk of IMD among children in Greece.

Second hand smoke exposure and the risk of invasive meningococcal disease in children: systematic review and meta-analysis

Background

Invasive meningococcal disease remains an important cause of serious morbidity and mortality in children and young people. There is a growing body of literature to suggest that exposure to passive smoke may play a role in the development of the disease, therefore we have performed a systematic review to provide a comprehensive estimate of the magnitude of this effect for smoking by any household member, by individual family members, and of maternal smoking before and after birth.

Methods

Four databases (Medline, Embase, PsychINFO and CAB Abstracts database) were searched to identify studies (to June 2012) and reference lists scanned for further studies. Titles, abstracts and full texts were checked for eligibility independently by two authors. Quality of included studies was assessed using the Newcastle-Ottawa Scale. Pooled odds ratios (OR) with 95% confidence intervals (CI) were estimated using random effect models, with heterogeneity quantified using I².

Results

We identified 18 studies which assessed the effects of SHS on the risk of invasive meningococcal disease in children. SHS in the home doubled the risk of invasive meningococcal disease (OR 2.18, 95% CI 1.63 to 2.92, I² = 72%), with some evidence of an exposure-response gradient. The strongest effect was seen in children under 5 years (OR 2.48, 95% CI 1.51 to 4.09, I² = 47%). Maternal smoking significantly increased the risk of invasive meningococcal disease by 3 times during pregnancy (OR 2.93, 95% CI 1.52-5.66) and by 2 times after birth (OR 2.26, 95% CI 1.54-3.31).

Conclusions

SHS exposure, and particularly passive foetal exposure to maternal smoking during pregnancy, significantly increases the risk of childhood invasive meningococcal disease. It is likely that an extra 630 cases of invasive meningococcal disease annually in children under 16 are directly attributable to SHS exposure in UK homes.

Carriage rates and serogroups of Neisseria meningitidis among freshmen in a University dormitory in Korea

PURPOSE

Neisseria meningitidis is a leading cause of bacterial meningitis in young adults. University students, especially those living in dormitories, have been known to be at increased risk of meningococcal disease. We performed a longitudinal study to determine the carriage rates of N. meningitidis and the changes thereof.

MATERIALS AND METHODS

We recruited Inha University freshmen who were, at that time, admitted to a student dormitory. A pharyngeal swab was taken from all participant who were also asked to complete a questionnaire. This was repeated four weeks later.

RESULTS

A total of 136 students were enrolled at the first culture. After four weeks, 128 students were enrolled, including 106 re-participants. The overall carriage rates changed from 11.8% to 14.1%. In analysis of the 106 re-participants, "visiting to pubs" was associated with carriage of N. meningitis for both the first (p=0.047) and second cultures (p=0.026). Serogroup C was found to be the most frequent serogroup (5 isolates), while 3 isolates were found from serogroup B. The most prevalent PorA types were P1.22,14-6 (4 isolates) and P1.19,15 (3 isolates). The DNA sequences of PorA VR2 were changed in 2 students during prolonged carriage.

CONCLUSION

The meningococcal carriage rate among first year university students who resided in a dormitory did not significantly increase over 4-week interval between cultures, which is markedly different from those reported in Western studies. Close social contact appeared to be related with carriage. Our data also revealed diversity in PorA types, suggesting the possibility of rapid mutation of the PorA gene during the 4-week interval.

The impact of smoking on oral and nasopharyngeal bacterial flora

Exposure to direct and passive tobacco smoking has significant impact on the gingival and oropharyngeal flora. The effects of exposure to smoking are evident in both children as well as adults. It increases the acquisition of periodontal pathogens and periodontal disease, colonization by respiratory pathogens, and the occurrence of upper respiratory tract infections, including otitis media. The flora of smokers contains fewer aerobic and anaerobic organisms with interfering activity against bacterial pathogens and harbors more potential pathogens as compared with the flora of non-smokers. The high number of pathogens and the low number of interfering organisms found in the nasopharynx of smokers revert to normal levels after complete cessation of smoking. Since parents who smoke harbor more potential pathogens and fewer interfering organisms, they may serve as a source of pathogens that can colonize and/or infect their children. The reduction in the number of members of the normal flora that interfere with the growth of pathogens and the greater adherence of bacterial pathogens to the oral mucosa are associated with the greater frequency of respiratory infections. Analysis of the data presented illustrates the adverse effects of direct and indirect exposure to smoking on colonization with potential pathogens.

Association of secondhand smoke exposure with pediatric invasive bacterial disease and bacterial carriage: a systematic review and meta-analysis

BACKGROUND

A number of epidemiologic studies have observed an association between secondhand smoke (SHS) exposure and pediatric invasive bacterial disease (IBD) but the evidence has not been systematically reviewed. We carried out a systematic review and meta-analysis of SHS exposure and two outcomes, IBD and pharyngeal carriage of bacteria, for Neisseria meningitidis (N. meningitidis), Haemophilus influenzae type B (Hib), and Streptococcus pneumoniae (S. pneumoniae).

METHODS AND FINDINGS

Two independent reviewers searched Medline, EMBASE, and selected other databases, and screened articles for inclusion and exclusion criteria. We identified 30 case-control studies on SHS and IBD, and 12 cross-sectional studies on SHS and bacterial carriage. Weighted summary odd ratios (ORs) were calculated for each outcome and for studies with specific design and quality characteristics. Tests for heterogeneity and publication bias were performed. Compared with those unexposed to SHS, summary OR for SHS exposure was 2.02 (95% confidence interval [CI] 1.52-2.69) for invasive meningococcal disease, 1.21 (95% CI 0.69-2.14) for invasive pneumococcal disease, and 1.22 (95% CI 0.93-1.62) for invasive Hib disease. For pharyngeal carriage, summary OR was 1.68 (95% CI, 1.19-2.36) for N. meningitidis, 1.66 (95% CI 1.33-2.07) for S. pneumoniae, and 0.96 (95% CI 0.48-1.95) for Hib. The association between SHS exposure and invasive meningococcal and Hib diseases was consistent regardless of outcome definitions, age groups, study designs, and publication year. The effect estimates were larger in studies among children younger than 6 years of age for all three IBDs, and in studies with the more rigorous laboratory-confirmed diagnosis for invasive meningococcal disease (summary OR 3.24; 95% CI 1.72-6.13).

CONCLUSIONS

When considered together with evidence from direct smoking and biological mechanisms, our systematic review and meta-analysis indicates that SHS exposure may be associated with invasive meningococcal disease. The epidemiologic evidence is currently insufficient to show an association between SHS and invasive Hib disease or pneumococcal disease. Because the burden of IBD is highest in developing countries where SHS is increasing, there is a need for high-quality studies to confirm these results, and for interventions to reduce exposure of children to SHS.

Modifiable risk factors for invasive meningococcal disease during an Edmonton, Alberta outbreak, 1999-2002

BACKGROUND

An outbreak of invasive meningococcal disease (IMD) in metro Edmonton, Alberta, Canada between December 1999 and June 2002 resulted in 84 laboratory-confirmed cases. Most cases were infected with Neisseria meningitidis serogroup C, and the highest age-specific incidence was observed in the 15-19 year age group.

METHODS

A case-control study was conducted to identify modifiable IMD risk factors among outbreak cases. Two controls were matched to each case on age and sex, and were recruited through random-digit dialing. A questionnaire was telephone-administered to 132 study participants (44 cases, 88 controls). Conditional logistic regression was utilized to calculate risk measures.

RESULTS

Multivariate analysis revealed three statistically significant risk factors: bar patronage (OR 35.2; 95% CI: 2.64-468), "rave" attendance (OR 12.8; 95% CI: 1.47-111) and maternal smoking (OR 8.88; 95% CI: 1.67-47.4). Humidifier use in the home was protective (OR 0.07; 95% CI: 0.009-0.64).

CONCLUSION

While the precision of risk estimates was low in the multivariate model, this study has identified rave attendance as an emergent IMD risk factor.

Lessons from meningococcal carriage studies

Neisseria meningitidis, an obligate commensal of humans, normally colonizes the mucosa of the upper respiratory tract without affecting the host, a phenomenon known as carriage. In Europe, as much as 35% of young adults are carriers at a given time. Recent studies using molecular methods for clone identification have demonstrated the extensive genetic diversity of the strains isolated from carriers, in comparison with a limited number of hypervirulent strains associated with invasive disease. Published studies and new data generated through the framework of the EU-MenNet clearly indicated significant differences in pathogenicity between meningococcal clones and in the distribution of multilocus sequence types among isolates from asymptomatic carriers among European countries; simultaneous carriage of more than one meningococcal strain in the throat is rare, but occasionally occurs; and the commensal association of particular clones with a host is a long-term relationship, often lasting several months. Further investigations of the carrier state are warranted to improve our understanding of the epidemiology and pathogenesis of meningococcal disease, as well as to support the introduction and to measure the impact of mass vaccination.

Social behavior and meningococcal carriage in British teenagers

Understanding predisposing factors for meningococcal carriage may identify targets for public health interventions. Before mass vaccination with meningococcal group C conjugate vaccine began in autumn 1999, we took pharyngeal swabs from ≈14,000 UK teenagers and collected information on potential risk factors. Neisseria meningitidis was cultured from 2,319 (16.7%) of 13,919 swabs. In multivariable analysis, attendance at pubs/clubs, intimate kissing, and cigarette smoking were each independently and strongly associated with increased risk for meningococcal carriage (p<0.001). Carriage in those with none of these risk factors was 7.8%, compared to 32.8% in those with all 3. Passive smoking was also linked to higher risk for carriage, but age, sex, social deprivation, home crowding, or school characteristics had little or no effect. Social behavior, rather than age or sex, can explain the higher frequency of meningococcal carriage among teenagers. A ban on smoking in public places may reduce risk for transmission.

Is it exposure to cigarette smoke or to smokers which increases the risk of meningococcal disease in teenagers?

BACKGROUND

Passive smoking appears to increase the risk of meningococcal disease (MD) in adolescents. Whether this effect is attributable to exposure to cigarette smoke or contact with smokers is unknown.

METHODS

We conducted a prospective population-based case-control study with age, sex matched-controls in 1:1 matching. Participants were 15-19 year old with MD recruited at hospital admission in six regions (65% of the population of England) from January 1999 through June 2000, and their matched controls. Data on potential risk factors were gathered by confidential interview, including seven passive smoking variables. Factor analysis was performed to assess the dimensionality of the passive smoking exposure variables. The data were analysed with univariate and multivariate conditional logistic regression.

RESULTS

144 case-control pairs were recruited (51% male; median age 17.6). Factor analysis identified two independent factors representing passive smoking (P < 0.01), one associated with 'exposure to smoke', the other with 'smoker contact'. Only smoker contact was a significant risk factor for MD (OR = 1.8; 95% CI 1.0-3.3; P = 0.05). In multivariate analysis this factor was still associated with MD independently of potential confounders such as active smoker status and household crowding.

CONCLUSION

Contact with smokers is associated with increased risk of MD in adolescents. This is more likely to be due to higher carriage rates in smokers than to exposure to smoke and emphasizes the importance of public health measures to stop smoking. In epidemiological studies that assess risk from passive smoking, exposure to smoke should be differentiated where possible from contact with smokers.

Carriage of Neisseria meningitidis by Greek children: risk factors and strain characteristics

Oropharyngeal swabs were cultured from 554 children aged 2-19 years attending nurseries, primary schools and secondary schools in the central Athens area. A questionnaire was completed to identify risk factors for carriage. Susceptibility to antimicrobial agents was determined by Etest. The genetic relatedness of the strains was examined by pulsed-field gel electrophoresis (PFGE), and isolate serogrouping was performed by slide agglutination. Twenty-two (4%) children were carriers of Neisseria meningitidis; seven isolates belonged to serogroup C, and five to serogroup B. One isolate was resistant to co-trimoxazole, and five showed intermediate resistance to penicillin. DNA analysis of 16 isolates revealed six distinct PFGE patterns. Clusters with indistinguishable PFGE patterns were noted in the same school. More than one serogroup was included in the same clonal group. On multivariate logistic regression analysis, only age > 12 years remained independently associated with the carrier state (odds ratio, 7.96; 95% CI, 2.24-28.33; p < 0.001). Overall, the N. meningitidis carriage rate among Greek schoolchildren increased with age, and the predominant serogroups in the Athens region were groups C and B. These findings may have important implications for future immunisation strategies with conjugate vaccines.

Carriage ofNeisseria meningitidisandNeisseria lactamicain northern Greece

In response to an increase in the number of cases of invasive meningococcal disease (IMD) in northern regions of Greece, a survey was carried out to determine if there was an increase in carriage of Neisseria meningitidis, particularly in areas where there have been increases in immigrant populations from neighbouring countries. The second objective was to determine if there was an increase in the serogroup C:2a:P1.5,2 a phenotype associated with recent outbreaks or changes in antibiotic sensitivities. As carriage of Neisseria lactamica is associated with development of natural immunity to IMD, the third objective was to determine the carriage rate of N. lactamica in this population. Among 3167 individuals tested, meningococci were isolated from 334 (10.5%). Compared with our previous studies, the proportion of meningococcal carriers was significantly increased among children in secondary education (11.3%) (chi2=9.67, P<0.005) and military recruits (37.4%) (chi2=21.11, P<0.000). Only 5/334 (1.5%) isolates expressed the phenotype associated with the increase in IMD in Greece. N. lactamica was isolated from 146/3167 (4.6%) participants. It was isolated from 71/987 (7.2%) children attending primary or nursery schools; however, the highest proportion of carriers (11.3%) was found in the boarding school for young Albanian men. In the 21-59-year age range, the majority of N. lactamica isolates (22/25, 88%) were from women, probably due to closer or more prolonged contact with children in the primary school age range. Smoking was significantly associated with isolation of meningococci from men but not from women. Penicillin-insensitive strains (25/334, 7.5%) were identified in all four regions examined; the majority (14/25, 56%) were obtained from military personnel. We conclude that there was a higher proportion of carriers in the population of northern Greece; however, the increase in carriage rate was not associated with the influx of immigrants from neighbouring countries, and there was not a higher incidence of the C:2a:P1.5,2 strain responsible for increased disease activity in Greece in either the immigrant or local populations.

Asthma management and environmental tobacco smoke exposure reduction in Latino children: a controlled trial

OBJECTIVES

This study tested the efficacy of coaching to reduce environmental tobacco smoke (ETS) exposure among asthmatic Latino children.

DESIGN

After asthma management education, families were randomly assigned to no additional service (control condition) or to coaching for ETS exposure reduction (experimental condition).

SETTING

The study was conducted in San Diego, California.

PARTICIPANTS

Two hundred four Latino children (ages 3-17 years) with asthma participated.

INTERVENTION

Approximately 1.5 hours of asthma management education was provided; experimental families also obtained 7 coaching sessions ( approximately 45 minutes each) to reduce ETS exposure.

OUTCOME MEASURES

Reported ETS exposure and children's urine cotinine were measured.

RESULTS

Parents in the coached condition reported their children exposed to significantly fewer cigarettes than parents of control children by 4 months (postcoaching). Reported prevalence of exposed children decreased to 52% for the coached families, but only to 69% for controls. By month 4, mean cotinine levels decreased among coached and increased among control children. Cotinine prevalence decreased from 54% to 40% among coached families, while it increased from 43% to 49% among controls. However, cotinine levels decreased among controls to the same level achieved by coached families by the 13-month follow-up.

CONCLUSIONS

Asthma management education plus coaching can reduce ETS exposure more than expected from education alone, and decreases in the coached condition may be sustained for about a year. The delayed decrease in cotinine among controls is discussed.

Epidemiology of bacterial meningitis

Bacterial meningitis caused by Haemophilus influenzae type B (Hib) has almost disappeared from the United States, Canada, and other countries that have implemented routine vaccination with Hib conjugate vaccines. The overall incidence of meningitis in these countries has declined by more than 50%, and the age distribution of susceptibility has shifted, so that the disease is now more common in adults than in children. Another new feature of the epidemiology of bacterial meningitis has been the occurrence of clusters of meningococcal disease. Such clusters have been school related, mainly in adolescents, and most clusters have been associated with a clone of group C, serotype 2a. The role of cigarette smoking as a risk factor for bacterial meningitis has been confirmed and adds urgency to the efforts to control smoking in adolescents and young adults.

Meningococcal carriage in relation to an outbreak of invasive disease due to Neisseria meningitidis serogroup C in the Netherlands

BACKGROUND

a cross-sectional study on meningococcal carriage was performed in Putten, a small rural town in the Netherlands where an unusual high incidence of invasive meningococcal disease (IMD) due to Neisseria meningitidis C:2a:P1.5 occurred. The outbreak was controlled by mass vaccination of all inhabitants aged 2 to 20 years.

METHODS

meningococcal carriage was studied in three groups: (1) a systematic age-specific sample of 2-20 year olds who visited the immunization clinic in Putten (January 1998: n=411); (2) children and adolescents in the same age range recruited through a kindergarten and schools in Venlo, a town where the causative strain of IMD had not been encountered (February 1998; n=374); (3) all initial carriers in Putten and a sample of non-carriers in that town (March 1998: n=145). Oropharyngeal swabs were taken for the purpose of isolating N. menigitidis.

RESULTS

the prevalence of carriage was 12.4% in Putten and 18.2%, in Venlo, but the prevalence of group C meningococci was higher in Putten (1.7%) than Venlo (0.5%). N. meningitidis C:2a:P1.5 was isolated twice in Putten and not at all in Venlo. A second examination in Putten showed that 18 of the 22 repeatedly tested carriers were still carriers, and six new carriers were found among the 55 initial non-carriers. Of the two known carriers of C:2a:P1.5, one was still carrying the same strain, and the other did not participate in the second investigation. Carriage was associated with increasing family size, discotheque visits and visits to youth clubs and sports clubs. In contrast, visits to the swimming pool appeared to be related to a lower risk, as was recent antibiotic use.

CONCLUSION

the prevalence of carriage with the invasive strain C:2a:P1.5 was low in the population that experienced a community-wide outbreak recently: the specific strain was not found in the reference population. This indicates a relatively high risk of developing the invasive disease for those who become infected with such strains.

Maternal cigarette smoking and invasive meningococcal disease: a cohort study among young children in metropolitan Atlanta, 1989-1996

OBJECTIVES

This study assessed the association between maternal cigarette smoking during pregnancy and the risk of invasive meningococcal disease during early childhood.

METHODS

Using a retrospective cohort study design, cases from an active surveillance project monitoring all invasive meningococcal disease in the metropolitan Atlanta area from 1989 to 1995 were merged with linked birth and death certificate data files. Children who had not died or acquired meningococcal disease were assumed to be alive and free of the illness. The Cox proportional hazards analysis was used to assess the independent association between maternal smoking and meningococcal disease.

RESULTS

The crude rate of meningococcal disease was 5 times higher for children whose mothers smoked during pregnancy than for children whose mothers did not smoke (0.05% vs 0.01%). Multivariate analysis revealed that maternal smoking (risk ratio [RR] = 2.9; 95% confidence interval [CI] = 1.5, 5.7) and a mother's having fewer than 12 years of education (RR = 2.1; 95% CI = 1.0, 4.2) were independently associated with invasive meningococcal disease.

CONCLUSIONS

Maternal smoking, a likely surrogate for tobacco smoke exposure following delivery, appears to be a modifiable risk factor for sporadic meningococcal disease in young children.

The effect of cigarette smoke on adherence of respiratory pathogens to buccal epithelial cells

Smoking is associated with an increased risk of respiratory tract infection in adults. In children, exposure to cigarette smoke is a risk factor for respiratory tract infection and bacterial meningitis: Active smoking and passive exposure to cigarette smoke is also associated with carriage of some potentially pathogenic species of bacteria in both adults and children. The aims of the study were to determine the effect of active smoking on: (1) bacterial binding to epithelial cells; (2) expression of host cell antigens that act as receptors for some species; and (3) the effects of passive exposure to water-soluble components of cigarette smoke on bacterial binding. Flow cytometry was used to assess binding to buccal epithelial cells of the following species labelled with fluorescein isothiocyanate: Neisseria meningitidis, Neisseria lactamica, Streptococcus pneumoniae, Bordetella pertussis, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus. Flow cytometry was also used to assess expression of host cell antigens which have been identified as bacterial receptors. For each species, binding to cells of smokers was significantly higher than to cells of non-smokers; however, expression of host cell antigens was similar on epithelial cells of both groups. Non-dilute cigarette smoke extract reduced binding of bacteria to epithelial cells, but dilutions between 1 in 10 and 1 in 320 enhanced binding. We conclude that smokers might be more densely colonised by a variety of potentially pathogenic bacteria. The enhanced bacterial binding to epithelial cells of smokers is not related to enhanced expression of host cell antigens that can act as receptors for some species, but possibly to components in the smoke that alter charge or other properties of the epithelial cell surface. Passive coating of mucosal surfaces with components of cigarette smoke might enhance binding of potentially pathogenic bacteria.

Carriage of Neisseria meningitidis and Neisseria lactamica among ethnic Greek school children from Russian immigrant families in Athens

During February and March 1995, a survey of meningococcal carriage in 625 school children was carried out in a suburb of Athens in which there was a large number of ethnic Greeks who had immigrated from Russia beginning in the early 1990s. The objectives of the study were: (1) to determine if factors associated with carriage of meningococci observed in a previous study of Greek school children were similar for the immigrant population; (2) to compare phenotypic characteristics of meningococci from the immigrant population with those isolated from children in Athens. Overall isolation rate for meningococci was 82/625 (13.1%), significantly higher than that found for school children in Athens (5.8%) during the winter of 1990 1991 (5.8%) (chi=25.98, P=0.0000003). By univariate analysis, carriage was not associated with sex, number of individuals per household, blood group, secretor status, socioeconomic level or maternal smoking; however, it was associated with fathers' smoking. The high proportion of men who smoked compared with the low proportion of women smokers might contribute to this finding. The main serogroup of meningococci isolated from this population was A (28%). While serogroup A appears to be more prevalent among Russian and Kurdish immigrants (14%) than among Greek school children or military recruits (4%), there has not been an increase in group A meningococcal disease in Greece. The isolation rate for N. lactamica was high 105/625 (17.3%). A few of these strains bound some of the monoclonal antibodies used for meningococcal serotyping and subtyping, and they are being examined in greater detail.

Meningococcal disease in Los Angeles County, California, and among men in the county jails

BACKGROUND

From January through March 1993, there were 54 cases of meningococcal disease in Los Angeles County, California, of which 9 occurred among men incarcerated in the county's jail system, which was 40 percent above capacity at the time. Several of the 45 patients from the community had had contact with men recently released from a county jail.

METHODS

We interviewed patients from the community (n=42) and neighborhood controls matched with the patients for age, race, and ethnic group (n=84) about potential exposures. We collected and cultured pharyngeal swabs for Neisseria meningitidis from men entering the central jail (n=162), men leaving the central jail (n=379), members of the jail staff (n=121), and patients at a community health center (n=214). Meningococcal isolates were identified by serotyping and multilocus enzyme electrophoresis.

RESULTS

The presence of community-acquired meningococcal disease was strongly associated with exposure to a person who had been in or worked at one of the county jails (multivariate matched odds ratio, 18.5; 95 percent confidence interval, 3.8 to 90.8; P<0.001). Pharyngeal carriage of meningococcus was significantly more frequent among men released from jail (19 percent) or entering jail (17 percent) than among workers at the jails (3 percent) or community residents seen at the clinic (1 percent). Among men entering jail, those who had previously been incarcerated were more often carriers than those who had not (21 percent vs. 7 percent, P=0.03). Of the isolates from nine community residents with serogroup C meningococcal disease, eight were the same strain as that isolated from the eight inmates with serogroup C disease.

CONCLUSIONS

In this outbreak of meningococcal disease in Los Angeles County, nearly half of community residents with the disease had contact with persons who had been in a county jail. The high rates of carriage among recidivists and released inmates suggests that the men became meningococcal carriers while in jail.