Changes in the Molecular Epidemiology of Pediatric Bacterial Meningitis in Senegal After Pneumococcal Conjugate Vaccine Introduction.

BACKGROUND: Bacterial meningitis is a major cause of mortality among children under 5 years of age. Senegal is part of World Health Organization-coordinated sentinel site surveillance for pediatric bacterial meningitis surveillance. We conducted this analysis to describe the epidemiology and etiology of bacterial meningitis among children less than 5 years in Senegal from 2010 and to 2016. METHODS: Children who met the inclusion criteria for suspected meningitis at the Centre Hospitalier National d'Enfants Albert Royer, Senegal, from 2010 to 2016 were included. Cerebrospinal fluid specimens were collected from suspected cases examined by routine bacteriology and molecular assays. Serotyping, antimicrobial susceptibility testing, and whole-genome sequencing were performed. RESULTS: A total of 1013 children were admitted with suspected meningitis during the surveillance period. Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus accounted for 66% (76/115), 25% (29/115), and 9% (10/115) of all confirmed cases, respectively. Most of the suspected cases (63%; 639/1013) and laboratory-confirmed (57%; 66/115) cases occurred during the first year of life. Pneumococcal meningitis case fatality rate was 6-fold higher than that of meningococcal meningitis (28% vs 5%). The predominant pneumococcal lineage causing meningitis was sequence type 618 (n = 7), commonly found among serotype 1 isolates. An ST 2174 lineage that included serotypes 19A and 23F was resistant to trimethoprim-sulfamethoxazole. CONCLUSIONS: There has been a decline in pneumococcal meningitis post-pneumococcal conjugate vaccine introduction in Senegal. However, disease caused by pathogens covered by vaccines in widespread use still persists. There is need for continued effective monitoring of vaccine-preventable meningitis.

Impact of rotavirus vaccine on acute gastroenteritis in children under 5 years in Senegal: Experience of sentinel site of the Albert Royer Children's Hospital in Dakar.

BACKGROUND: Acute gastroenteritis (AGE) is a leading cause of morbidity and mortality among children <5 years of age in developing countries, with rotavirus being the most common infectious etiology. In November 2014, monovalent rotavirus vaccine was introduced in Senegal. We determined the impact of rotavirus vaccine on hospitalizations for all-cause and rotavirus related AGE in children <60 months of age. METHODS: We examined two data sources from the national referral hospital. Using sentinel surveillance data from March 2011 to February 2017, we examined the proportion of AGE hospitalizations among children <60 months of age attributable to rotavirus, stratified by age groups (0-11, 12-23 and 24-59 months). Using pediatric logbook data from March 2010 to February 2017, we examined the proportion of all childhood hospitalizations attributable to AGE, among the same age groups. RESULTS: In sentinel surveillance, 673 patients <60 months were hospitalized for AGE, with 30% (203/673) due to rotavirus. In pre-vaccine years, the median proportion of rotavirus-positive hospitalizations was 42%; this proportion declined by 76% to 10% rotavirus positive in 2015-2016 (p < .001) and by 59% to 17% in 2016-2017 (p < .001). From the logbook data, among all children <60 months, a median of 11% of all hospitalizations in the pre-vaccine period were due to AGE, with 2015-2016 seeing a 16% decline (p < .001), to 9% of all hospitalizations, and 2016-2017 seeing a 39% decline (p < .001), to 7% of all hospitalizations. Declines in both rotavirus-associated and all-cause AGE hospitalizations were most marked among infants, with a suggestion of herd effect among older children seen in the surveillance data. CONCLUSION: Rotavirus vaccine demonstrated a significant impact on rotavirus-associated hospitalizations and all-cause AGE hospitalizations in the first two seasons after vaccine introduction in Senegal. Our data support the continued use of this vaccine in national immunization program.

Analysis of fliC variation among clinical isolates of Burkholderia cepacia.

PCR and restriction fragment length polymorphism (RFLP) typing of flagellin genes (fliC) from 57 clinical isolates of Burkholderia cepacia indicated that only type 11 flagellins were present. Twenty-two isolates previously identified as the epidemic UK cystic fibrosis strain were indistinguishable by this method, as were 11 isolates from a pseudo-outbreak in Senegal. Other clinical isolates, including 19 from disparate sources in Malaysia, were separated into nine fliC RFLP groups, exhibiting a large degree of divergence. When isolates were indistinguishable by fliC genotyping, their similarity was confirmed by whole genome macro-restriction analysis with pulsed-field gel electrophoresis following XbaI digestion. The variation in fliC sequences of B. cepacia was far greater than that with B. pseudomallei, supporting the view that 'B. cepacia', as currently defined, may comprise several different genomic species.