In order to investigate carriage status and serum groups distribution of Neisseria meningitidis(Nm) among healthy population in Jiangsu Province, four counties were selected as monitoring sites by random sampling method for cross-sectional study. Throat swab specimens were collected from four monitoring sites in October to November 2019 and November to December 2020 for bacterial culture and Real-time PCR detection. Chi-square test was used to compare the positive rate of Neisseria meningitidis, and multiple logistic regression model was used to analyze the influencing factors of Neisseria meningitidis carrier rate. The results showed that among 1 512 samples, 57 strains of Nm were isolated, and the carrier rate was 3.77%. Serogroup B was the dominant group (36.84%), followed by un-known serogroups (33.33%), serogroup C was the third (17.54%), serogroup W135 and serogroup A were 7.02% and 5.26%, respectively. The carriage rate (8.60%) of 15-20 years old was significantly higher than others (1.77%-3.74%)(Pearson χ²=18.211, P<0.05). Region, age and immunization history were risk factors for Neisseria meningitidis carrier rate. In summary, the Nm carrier rate of healthy population in Jiangsu Province is relatively low, which indicates that the epidemic cases will continue to be sporadic in the future. However, the prevention and control of meningococcal epidemics on campus should be strengthened, and the monitoring of neisseria meningitidis group B should be maintained as it has become the dominant epidemic strain.
Humans ; Adolescent ; Young Adult ; Adult ; Neisseria meningitidis ; Meningococcal Infections/prevention & control* ; Prevalence ; Cross-Sectional Studies ; Carrier State/microbiology*

The carriage rate and serotype distribution of Streptococcus pneumoniae (S. pneumoniae) in a healthy population in China remains unclear. In this study, we collected the oropharyngeal swabs from 513 individuals in Xinjiang, China. Real-time PCR targeting the lytA gene and 12 serotypes were assessed to identify S. pneumoniae carriage. The total carriage rate of S. pneumoniae was 70.4% (361/513). The most prevalent serotypes were 19B/F, 18B/C, 5, and 6A/B. The highest carriage rate of S. pneumoniae was noted in children aged 6-10 years (88.6%), which merits further attention. The co-colonization rate of two or more S. pneumoniae serotypes was 79.8% (264/331). This study aimed to investigate the baseline pneumococcal carriage rate among healthy individuals in China to improve our understanding of the epidemiology of S. pneumoniae.
Adolescent ; Adult ; Carrier State ; epidemiology ; microbiology ; Child ; Child, Preschool ; China ; epidemiology ; Cross-Sectional Studies ; Female ; Humans ; Infant ; Male ; Middle Aged ; Pneumococcal Infections ; epidemiology ; microbiology ; Prevalence ; Real-Time Polymerase Chain Reaction ; Serogroup ; Streptococcus pneumoniae ; classification ; genetics ; isolation & purification ; Young Adult

OBJECTIVETo study the relationship between nasal carriage and Staphylococcus aureus (S. aureus) infection in hospitalized children.

METHODSFifty-six hospitalized children infected with S. aureus were recruited in this study. Nasal swabs were collected and cultured, and the nasal carriage rate of S. aureus was examined. PVL virulence gene and mecA resistance gene were both detected in clinical strains and nasal carriage strains by PCR.

RESULTSTwenty-two (39%) of the 56 children had nasal carriage of S. aureus, and most of them (18 cases) were younger than one year. Among these 22 children, 11 (50%) had previous hospitalization over the past year. In the infected strains, the rate of methicillin-resistant S. aureus (MRSA) was 29% (16/56), while it was 32% (7/22) in carriage strains. The mecA positive results in clinical strains were consistent with the results in nasal carriage strains. Among 5 PVL-positive nasal carriage strains, 4 (90%) could be matched with their clinical strains, all of which were MRSA.

CONCLUSIONSNasal carriage is a potential risk factor for S. aureus infection. Nosocomial transmission may lead to nasal carriage, which can cause S. aureus infection. The isolation rate of MRSA is high in hospitalized children infected with S. aureus, which implies that more attention is needed for this situation. The isolates from noses may be clonally identical to the isolates from clinical secretions, and the homology between them needs to be confirmed by multi-locus sequence typing.

Bacterial Proteins ; genetics ; Carrier State ; microbiology ; Child ; Child, Hospitalized ; Child, Preschool ; Female ; Humans ; Infant ; Infant, Newborn ; Male ; Methicillin-Resistant Staphylococcus aureus ; isolation & purification ; Nose ; microbiology ; Penicillin-Binding Proteins ; Staphylococcal Infections ; microbiology ; Staphylococcus aureus ; isolation & purification

OBJECTIVETo investigate nasopharyngeal carriage rate, antimicrobial resistance and serotype distribution of Streptococcus pneumoniae among children with upper respiratory infection.

METHODSNasopharygeal swabs were collected from children with upper respiratory infection visiting the outpatient department of Beijing Children′s Hospital between March 2013 and February 2014. The antibiotic susceptibility was tested by Etest method, and the serotype was determined by Quellung reaction.

RESULTSThe nasopharyngeal carriage rate for Streptococcus pneumoniae was 23.8% (699/2 941). One hundred isolates were randomly chosen for antimicrobial susceptiblity test and serotyping. Up to 98.0% isolates were susceptible to parenteral penicillin. The susceptible rate against oral penicillin, however, was 33.0%. The non-susceptible rate to erythromycin and azithromycin was 97.0%. The multi-drug resistance rate was up to 86.0%. The common serotypes were 6A(12.0%), 19F(12.0%), 6B(10.0%), 23F(9.0%) and 14(8.0%). The coverage rates of 7-, 10- and 13-valent pneumococcal conjugate vaccine were 41.0%, 42.0% and 59.0% respectively.

CONCLUSIONSAbout 25% of children with upper respiratory infection are nasopharyngeal colonized by Streptococcus pneumoniae. The isolates show a high antimicrobial resistance. The 13-valent pneumococcal conjugate vaccine covers about 60.0% of the isolates.

Adolescent ; Carrier State ; epidemiology ; microbiology ; Child ; Child, Preschool ; Drug Resistance, Bacterial ; Female ; Humans ; Infant ; Male ; Nasopharynx ; microbiology ; Pneumococcal Vaccines ; immunology ; Respiratory Tract Infections ; microbiology ; Serotyping ; Streptococcus pneumoniae ; classification ; drug effects ; isolation & purification

BACKGROUND: We investigated the rates of fecal transmission of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae (ESBL-E) and carbapenem-resistant Enterobacteriaceae (CRE) among patients admitted to intensive care units (ICUs). METHODS: From June to August 2012, rectal cultures were acquired from all patients at ICU admission. For patients not carrying ESBL-E or CRE at admission, follow-up cultures were performed to detect acquisition. A chromogenic assay was used to screen for ESBL-E and CRE. Bacterial species identification and antibiotic susceptibility tests were performed using the Vitek 2 system (bioMerieux, France). ESBL genotypes were determined by PCR, and clonal relatedness of the isolates was assessed by pulsed-field gel electrophoresis. RESULTS: Out of 347 ICU admissions, 98 patients were found to be carriers of ESBL-E (28.2%, 98/347). Follow-up cultures were acquired from 91 of the patients who tested negative for ESBL-E at admission; the acquisition rate in this group was 12.1% (11/91), although none was a nosocomial transmission. For CRE, the prevalence of fecal carriage was 0.3% (1/347), and the acquisition rate was 2.9% (4/140). None of the CRE isolates were carbapenemase-producers. CONCLUSIONS: The high prevalence of ESBL-E carriage on admission (28.2%), coupled with rare nosocomial transmission and the very low carriage rate of CRE (0.3%), challenge the routine use of active surveillance in non-epidemic settings. Nevertheless, passive surveillance measures, such as rapid and accurate screening of clinical specimens, will be critical for controlling the spread of CRE.
Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/*metabolism ; Carbapenems/*pharmacology ; Carrier State/epidemiology ; Cross Infection/epidemiology/*transmission ; DNA, Bacterial/analysis ; Drug Resistance, Bacterial/drug effects ; Electrophoresis, Gel, Pulsed-Field ; Enterobacteriaceae/enzymology/genetics/*physiology ; Enterobacteriaceae Infections/epidemiology/*transmission ; Feces/*microbiology ; Genotype ; Humans ; Intensive Care Units ; Polymerase Chain Reaction ; Prevalence ; Republic of Korea/epidemiology ; beta-Lactamases/*metabolism

OBJECTIVETo characterize the meningococcal strains isolated from cases and close contacts with meningococcal disease associated with an outbreak in a jail in May 2010 by investigating the national distribution of hyperinvasive ST-4821 serogroup C clone associated with this outbreak.

METHODSThe cases were described based on the clinical symptoms and laboratory results. Pharyngeal swabs were cultured for N. meningitidis from men in the jail. Meningococcal isolates were identified by serogrouping, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), respectively. Four hundred and sixteen serogroup C N. meningitidis strains were collected from 27 provinces between 2003 and 2010 for a nationwide survey and analyzed by PFGE and MLST.

RESULTSThree persons in a jail system were infected with invasive N. meningitidis serogroup C. All isolates tested had matching PFGE patterns and belonged to the multilocus sequence type (ST) 4821 clonal complex. All 47 N. meningitidis strains were identified from the pharyngeal swabs of 166 peoples in the jail, and 26 of them belonged to ST-4821 serogroup C clone, and 90.14% (375/416) serogroup C strains identified in the nationwide survey belonged to the ST-4821 complex. The ST-4821 serogroup C clone was spread nationwide, distributed in 24 provinces, especially in eastern provinces between 2003 and 2010.

CONCLUSIONEndemic transmission and carriage rate of ST-4821 serogroup C clone are high in this jail system. The ST-4821 serogroup C clone is spreading in China and nationwide distributed despite the existence of some effective vaccines.

Carrier State ; China ; epidemiology ; Disease Outbreaks ; Electrophoresis, Gel, Pulsed-Field ; Humans ; Meningitis, Meningococcal ; epidemiology ; microbiology ; Neisseria meningitidis ; genetics ; isolation & purification ; Pharynx ; microbiology ; Prisons

OBJECTIVETo investigate drug-resistance and carriage of virulence factors of Pseudomonas aeruginosa (Pa) isolated from children.

METHODThirty-eight strains of Pa were collected and isolated in pediatric clinic during 2006-2009, and tests were undertaken to identify bacteria and susceptibility test was performed using VITEK-2 COMPACT GNI and AST-GN13 cards. The virulence factors were confirmed by using polymerase chain reaction (PCR) and sequencing.

RESULTAll the 38 strains of Pa were resistant to ampicillin, ampicillin/sulbactam, cefazolin, nitrofurantoin, trimethoprim/sulfamethoxazole, resistance rates were 100%. Except for ceftriaxone (60.53%), the resistance rates to other antibiotics were all below 16%. PCR test showed that all the 38 strains of Pa carried exotoxin A(toxA) and nitric oxide reductase A (norA), however, detective ratio of the other virulence factors, exoenzyme Y (exoY) was 84.21% (32/38), exoenzyme S (exoS) 57.89% (22/38), pyocyanin (pyp) 42.11% (16/38), exoenzyme U (exoU) 34.21% (13/38), and 38 strains of Pa did not carry exoenzyme T (exoT) and elastase B (lasB) without exception. By analyzing tests, we discovered that 3 pan-drug resistant strains of Pa were all combination of exo U+/pyp+, there were 4 strains of Pa which were moderately-resistant to imipenem, including exoU+/pyp+/exoY+ (2 isolates), exo U+/pyp+ (1 isolate), and exoY+/exoS+ (1 isolates). It indicated that the drug-resistance rate of exoU+/pyp+ is much higher, compared with exoS+ and exoY+. Molecular epidemiological detection revealed that 2 of 3 extensive-resistance strains of Pa were the same clone, but another one had 96.3% of homology with them.

CONCLUSIONThe above mentioned 34.21% of Pa isolated from children carried virulence factors toxA, norA, exoS, exoY, pyp and exoU. The strains with exoU/pyp had rather high resistance. The strains with pyp had strong toxicity, they easily cause generalized infection, the patients with them had very high mortality.

ADP Ribose Transferases ; genetics ; Bacterial Proteins ; genetics ; Bacterial Toxins ; genetics ; Carrier State ; epidemiology ; microbiology ; Child ; Drug Resistance, Multiple, Bacterial ; genetics ; Exotoxins ; Genes, Bacterial ; Humans ; Microbial Sensitivity Tests ; Polymerase Chain Reaction ; Pseudomonas Infections ; epidemiology ; genetics ; microbiology ; Pseudomonas aeruginosa ; genetics ; isolation & purification ; pathogenicity ; Virulence Factors ; genetics

OBJECTIVETo evaluate the prevalence of nasal carriage of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) in healthy children from Chengdu.

METHODSStrains of Staphylococcus aureus were isolated from nasal swabs of healthy children from five kindergartens in Chengdu from September, 2005 to December, 2005 and questionnaires were obtained. Antibiotic susceptibility test was performed with agar disk diffusion and Bauer-Kirby on Mueller-Hinton medium method to determine CA-MRSA. mecA and PVL genes were detected with PCR in all of the CA-MRSA isolates.

RESULTSA total of 801 children were enrolled. Overall 147 children (18.4%) were carried with Staphylococcus aureus and 9 (1.1%) were carried with CA-MRSA. All CA-MRSA isolates were positive for mecA gene, and 5 CA-MRSA isolates were positive for PVL gene. Of the 9 CA-MRSA isolates, 6 were multiresistant.

CONCLUSIONSCA-MRSA nasal colonization is present among Chengdu healthy children. The CA-MRSA isolates are multiresistant and parts of CA-MRSA isolates carry PVL gene. The nasal carriage of CA-MRSA in healthy children should be a concerned issue.

Bacterial Proteins ; genetics ; Carrier State ; microbiology ; Child ; Child, Preschool ; China ; Community-Acquired Infections ; microbiology ; Female ; Humans ; Male ; Methicillin-Resistant Staphylococcus aureus ; genetics ; isolation & purification ; Microbial Sensitivity Tests ; Nose ; microbiology ; Penicillin-Binding Proteins

OBJECTIVETo study the prevalence rate of upper respiratory tract group A Streptococcus (GAS) carriage in school-age children from Xinjiang Province.

METHODSA total of 478 children at age of 9-12 years from Tulufan City and Buerjin County of Xinjiang Province were enrolled by random cluster sampling. Throat swab cultures were performed once each season for the determination of presence of GAS.

RESULTSIn the 1 827 samples, 196 GAS strains were isolated, with a GAS carrier rate of 10.7%. The prevalence rate of GAS carrier in Tulufan City ranged from 3.7%-16.5% compared with 4.7%-21.4% in Buerjin County (P < 0.05). The prevalence rate of GAS carrier in winter is the highest, followed by in autumn, spring and summer in both regions. There were significant differences in the GAS carriage rate in autumn between the two regions. There were no significant differences in the GAS carriage rate between boys and girls. Of the 196 GAS strains, 133 from Han, 22 from Uygur and 41 from Hazakh children. There were significant differences in the prevalence rate of GAS carriage among children with different ethic groups.

CONCLUSIONSThe prevalence rate of GAS carriage is high in school-age children from Tulufan and Buerjin of Xinjiang Province. The GAS carrier rate is associated with the season and ethic group. The children from Buerjin County present a higher GAS carrier rate than those from Tulufan City.

Carrier State ; microbiology ; Child ; China ; Female ; Humans ; Male ; Prevalence ; Respiratory System ; microbiology ; Streptococcus pyogenes ; isolation & purification

Bacterial Typing Techniques ; Carrier State ; microbiology ; Child ; Child, Preschool ; Drug Resistance, Bacterial ; Female ; Haemophilus ; classification ; drug effects ; Haemophilus Infections ; microbiology ; Humans ; Male ; Respiratory Tract Infections ; microbiology