Dataset Information

Longitudinal study of meningococcal carriage rates in university entrants living in a dormitory in South Korea.

ABSTRACT: University students, especially those living in dormitories, are known to have a high risk of invasive meningococcal disease. We performed a longitudinal study to investigate the change in Neisseria meningitidis carriage rates and identify the risk factors for carriage acquisition in university students in South Korea. We recruited university entrants who were admitted to a student dormitory. Pharyngeal swabs were taken from participants at baseline, 1 month, and 3 months, and the subjects completed a questionnaire. Culture and real-time polymerase chain reaction (PCR) for species-specific ctrA and sodC genes were performed. The cultured isolates or PCR-positive samples were further evaluated for epidemiologic characterization using serogrouping, PorA typing, FetA typing, and multilocus sequence typing (MLST). At the first visit, we enrolled 332 participants who were predominantly male (64.2%) with a median age of 19 years. Meningococcal carriage rates increased from 2.7% (95% confidence interval [CI] 0.9-4.4%) at baseline to 6.3% (95% CI 3.4-9.0%) at 1 month and 11.8% (95% CI 7.8-15.6%) at 3 months. Nongroupable isolates accounted for 50.0% of all isolates, with serogroup B being the next most prevalent (24.1%). In the study population, male sex (OR 2.613, 95% CI 1.145-5.961, p = 0.022) and frequent pub or club visits (OR 3.701, 95% CI 1.536-8.919, p = 0.004) were significantly associated with meningococcal carriage. Based on serotype and MLST analyses, six carriers transmitted meningococci to other study participants. N. meningitidis carriage rates among new university entrants who lived in a dormitory significantly increased within the first 3 months of dormitory stay, probably owing to the transmission of identical genotype among students. Based on the risk of meningococcal disease, meningococcal vaccination should be considered for students before dormitory admission.

SUBMITTER: Choi H

PROVIDER: S-EPMC7842983 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Longitudinal study of meningococcal carriage rates in university entrants living in a dormitory in South Korea.

Choi Heun H Lee Hyuk Min HM Lee Woonji W Kim Jun Hyoung JH Seong Hye H Kim Jung Ho JH Ahn Jin Young JY Jeong Su Jin SJ Ku Nam Su NS Yeom Joon-Sup JS Lee Kyungwon K Kim Hee Soo HS Oster Philipp P Choi Jun Yong JY

PloS one 20210128 1

University students, especially those living in dormitories, are known to have a high risk of invasive meningococcal disease. We performed a longitudinal study to investigate the change in Neisseria meningitidis carriage rates and identify the risk factors for carriage acquisition in university students in South Korea. We recruited university entrants who were admitted to a student dormitory. Pharyngeal swabs were taken from participants at baseline, 1 month, and 3 months, and the subjects compl ...[more]

PMID: 33507960

Similar Datasets

Project description:In the 1997-98 academic year, we conducted a longitudinal study of meningococcal carriage and acquisition among first-year students at Nottingham University, Nottingham, United Kingdom. We examined the dynamics of long-term meningococcal carriage with detailed characterization of the isolates. Pharyngeal swabs were obtained from 2,453 first-year students at the start of the academic year (October), later on during the autumn term, and again in March. Swabs were immediately cultured on selective media, and meningococci were identified and serologically characterized. Nongroupable strains were genetically grouped using a PCR-based assay. Pulsed-field gel electrophoresis was used to determine the link between sequential isolates. Of the carriers initially identified in October, 44.1% (98 of 222) were still positive later on in the autumn (November or December); 57.1% of these remained persistent carriers at 6 months. Of the index carriers who lost carriage during the autumn, 16% were recolonized at 6 months. Of 344 index noncarriers followed up, 22.1% acquired carriage during the autumn term and another 13.7% acquired carriage by March. Overall, 43.9% (397 of 904) of the isolates were noncapsulated (serologically nongroupable); by PCR-based genogrouping, a quarter of these belonged to the capsular groups B and C. The ratio of capsulated to noncapsulated forms for group B and C strains was 2.9 and 0.95, respectively. Sequential isolates of persistent carriers revealed that individuals may carry the same or entirely different organisms at different times. We identified three strains that clearly switched their capsular expression on and off at different times in vivo. One student developed invasive meningococcal disease after carrying the same organism for over 7 weeks. The study revealed a high rate of turnover of meningococcal carriage among students. Noncapsulated organisms are capable of switching their capsular expression on and off (both ways) in the nasopharynx, and group C strains are more likely to be noncapsulated than group B strains. Carriage of a particular meningococcal strain does not necessarily protect against colonization or invasion by a homologous or heterologous strain.

Project description:In January and February 2015, Neisseria meningitidis serogroup B (NmB) outbreaks occurred at two universities in the United States, and mass vaccination campaigns using MenB vaccines were initiated as part of a public health response. Meningococcal carriage evaluations were conducted concurrently with vaccination campaigns at these two universities and at a third university, where no NmB outbreak occurred. Meningococcal isolates (N = 1,514) obtained from these evaluations were characterized for capsule biosynthesis by whole-genome sequencing (WGS). Functional capsule polysaccharide synthesis (cps) loci belonging to one of seven capsule genogroups (B, C, E, W, X, Y, and Z) were identified in 122 isolates (8.1%). Approximately half [732 (48.4%)] of isolates could not be genogrouped because of the lack of any serogroup-specific genes. The remaining 660 isolates (43.5%) contained serogroup-specific genes for genogroup B, C, E, W, X, Y, or Z, but had mutations in the cps loci. Identified mutations included frameshift or point mutations resulting in premature stop codons, missing or fragmented genes, or disruptions due to insertion elements. Despite these mutations, 49/660 isolates expressed capsule as observed with slide agglutination, whereas 45/122 isolates with functional cps loci did not express capsule. Neither the variable capsule expression nor the genetic variation in the cps locus was limited to a certain clonal complex, except for capsule null isolates (predominantly clonal complex 198). Most of the meningococcal carriage isolates collected from student populations at three US universities were non-groupable as a result of either being capsule null or containing mutations within the capsule locus. Several mutations inhibiting expression of the genes involved with the synthesis and transport of the capsule may be reversible, allowing the bacteria to switch between an encapsulated and non-encapsulated state. These findings are particularly important as carriage is an important component of the transmission cycle of the pathogen, and understanding the impact of genetic variations on the synthesis of capsule, a meningococcal vaccine target and an important virulence factor, may ultimately inform strategies for control and prevention of disease caused by this pathogen.

Dataset Information

Longitudinal study of meningococcal carriage rates in university entrants living in a dormitory in South Korea.

Publications

Longitudinal study of meningococcal carriage rates in university entrants living in a dormitory in South Korea.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets