SUMMARYThis case control study investigated environmental factors in 74 confirmed cases of meningococcal disease (MD). In children aged under 5, passive smoking in the home (30 or more cigarettes daily) was associated with an odds ratio (OR) of 7 5 (95% confidence interval (CI) 1P46-38-66). ORs increased both with the numbers of cigarettes smoked and with the number of smokers in the household, suggesting a dose-response relationship. MD in this age group was also significantly associated with household overcrowding (more than 1P5 persons per room) (OR 60, 95% CI 110-32-8), with kisses on the mouth with 4 or more contacts in the previous 2 weeks (OR 2-46, 95% CI 1P09-5 56), with exposure to dust from plaster, brick or stone in the previous 2 weeks (OR 2-24, 95 % CI 107-465); and with changes in residence (OR 30, 95% CI 1P0-899), marital arguments (OR 3-0, 95 % CI 1P26-7 17) and legal disputes in the previous 6 months (OR 3-10, 95% CI 1P24-7 78). These associations were independent of social class. Public health measures to lower the prevalence of cigarette smoking by parents of young children may reduce the incidence of MD. The influence of building dust and stressful life events merits further investigation.

No abstract

SUMMARYBetween 1 October 1986 and 31 March 1987, 55 cases of meningococcal disease were identified in the South-West of England, an attack rate of 1-54 per 100000 during the study period. Antibiotics used in the treatment of the disease successfully eliminated nasopharyngeal carriage of meningococci in 13 out of 14 cases without use of rifampicin. The overall meningococcal carriage rate in 384 close contacts was 18-2 % and the carriage rate of strains indistinguishable from the associated case strain was 11 1 %. The carriage rate of indistinguishable strains in household contacts (16-0 %) was higher than the carriage rate in contacts living at other addresses (7 0 %, P < 0-05). A 2-day course of rifampicin successfully eradicated meningococci from 46 (98 %) of 47 colonized contacts.In one third of cases groupable meningococci were isolated from at least one household contact; 92 % of these isolates were of the same serogroup as the associated case strain. When a meningococcus is not isolated from a deep site in a clinical case of meningococcal disease, culture of serogroup A or C strains from nasopharyngeal swabs of the case or of household contacts is an indication that the close contact group should be offered meningococcal A + C vaccine in addition to chemoprophylaxis. The failure in this and other studies to isolate meningococci from any household contact in the majority of cases may be due either to the relative insensitivity of nasopharyngeal swabbing in detecting meningococcal carriage or to the acquisition of meningococci by most index cases from sources outside the household.

No abstract

In the years 1999-2000, there was an increase in the incidence of meningococcal disease in Victoria, largely caused by Neisseria meningitidis serogroup C. This change was associated with a shift in age distribution of cases, with relatively more disease appearing in the 15-29 year age group, and with 40/58 serogroup C isolates in 2000 exhibiting a new macrorestriction pattern (pattern A). Thirty-four of 52 pattern A isolates tested displayed the novel phenotype C:2a:P1.4, and were consistently porA VR type P1.7-2,4 by DNA sequencing. Nine of 10 representative pattern A isolates analysed displayed a housekeeping gene allele profile (ST-11) that is characteristic of the electrophoretic type (ET)-15 variant that has caused outbreaks in Canada, the Czech Republic and Greece. Meningococci belonging to the ST-11 complex that were isolated in Victoria prior to 1999 did not display either restriction pattern A or PorA VR type P1.7-2,4.