Effectiveness of a Meningococcal Group B Vaccine (4CMenB) in Children.

BACKGROUND: In September 2015, the four-component, protein-based meningococcal serogroup B vaccine (4CMenB; Bexsero) became available for private purchase in Spain. METHODS: We conducted a nationwide matched case-control study to assess the effectiveness of 4CMenB in preventing invasive meningococcal disease in children. The study included all laboratory-confirmed cases of invasive meningococcal disease in children younger than 60 months of age between October 5, 2015, and October 6, 2019, in Spain. Each case patient was matched with four controls according to date of birth and province. 4CMenB vaccination status of the case patients and controls was compared with the use of multivariate conditional logistic regression. RESULTS: We compared 306 case patients (243 [79.4%] with serogroup B disease) with 1224 controls. A total of 35 case patients (11.4%) and 298 controls (24.3%) had received at least one dose of 4CMenB. The effectiveness of complete vaccination with 4CMenB (defined as receipt of at least 2 doses, administered in accordance with the manufacturer's recommendations) was 76% (95% confidence interval [CI], 57 to 87) against invasive meningococcal disease caused by any serogroup, and partial vaccination was 54% (95% CI, 18 to 74) effective. Complete vaccination resulted in an effectiveness of 71% (95% CI, 45 to 85) against meningococcal serogroup B disease. Vaccine effectiveness with at least one dose of 4CMenB was 64% (95% CI, 41 to 78) against serogroup B disease and 82% (95% CI, 21 to 96) against non-serogroup B disease. With the use of the genetic Meningococcal Antigen Typing System, serogroup B strains that were expected to be covered by 4CMenB were detected in 44 case patients, none of whom had been vaccinated. CONCLUSIONS: Complete vaccination with 4CMenB was found to be effective in preventing invasive disease by serogroup B and non-serogroup B meningococci in children younger than 5 years of age.

Listeriosis: An emerging public health problem especially among the elderly.

OBJECTIVES: To analyze the incidence trend of listeriosis, its present epidemiology and the potential benefit of aminoglycosides during the last two decades. METHODS: We reviewed all cases of invasive listeriosis detected during a 22-year period in a large tertiary hospital. Two equal periods of 11 years were compared. RESULTS: We detected 111 cases of listeriosis (32 during the first 11-year period and 79 during the second). Incidence of listeriosis increased significantly (from 4.66/10(6) inhabitants to 10.39/10(6) inhabitants; P = .001). In the second period, there were more patients >65 years (21.9%-45.6%; P = .02) and with no significant underlying diseases (0 vs. 16.5%; P = .02). Comparing clinical presentations between the two periods, primary bacteremia increased (40.6% vs. 55.7%), while central nervous system infections decreased (34.4% vs. 27.8%). Cotrimoxazole (SXT) use increased significantly in the second period (from 6.3% to 40.5%, P = .001) while the administration of aminoglycosides decreased (from 40.6% to 21.5%, P = .04). The use of combination therapy did not have any impact on mortality, however it did increase toxicity. CONCLUSIONS: Listeriosis should be considered an emerging health problem, especially among the elderly, including those with no underlying medical conditions. The use of aminoglycosides does not seem to be justified according to our data.