scholarly journals Identification, prevalence and population structure of non-typable Streptococcus pneumoniae in carriage samples isolated from preschoolers attending day-care centres

Microbiology ◽  
2006 ◽  
Vol 152 (2) ◽  
pp. 367-376 ◽  
Author(s):  
Raquel Sá-Leão ◽  
Alexandra S. Simões ◽  
Sónia Nunes ◽  
Natacha G. Sousa ◽  
Nelson Frazão ◽  
...  
Keyword(s):  
Population Structure ◽  
Multidrug Resistance ◽  
Streptococcus Pneumoniae ◽  
Southern Blotting ◽  
Distinct Group ◽  
Specific Group ◽  
Resistance To Penicillin ◽  
Day Care Centres ◽  
Quellung Reaction ◽  
Sequence Types

The authors aimed to get insights into the population structure of non-(sero)typable pneumococci (NTPn), a specific group of natural atypical pneumococci whose identification is often difficult, and which has remained insufficiently studied. A total of 265 presumptive NTPn, isolated between 1997 and 2003 from the nasopharynx of children, were characterized. Strains were confirmed to be pneumococci on the basis of bile solubility, and PCR detection or Southern blotting hybridization of lytA and psaA, genes ubiquitous in this species. Multilocus sequence typing (MLST) was used to exclude two isolates that gave ambiguous results. Non-typability was confirmed by the Quellung reaction using Omniserum. A total of 213 isolates were considered to be true NTPn. The molecular analysis of the true NTPn by PFGE and MLST showed that this population was genetically diverse, although a dominant cluster, accounting for 66 % of the isolates, was identified. Antimicrobial resistance was observed in most genetic backgrounds, and multidrug resistance to penicillin, erythromycin, clindamycin, tetracycline and sulfamethoxazole-trimethoprim was associated with strains belonging to the dominant cluster. Comparison with PFGE fingerprints and sequence types of large collections of serotypable strains showed that the genetic backgrounds of all but two NTPn were different from those found in serotypable strains. In addition, we found that NTPn strains with similar genetic backgrounds to those identified in our study had been isolated from disease sources in other countries. These observations seem to indicate that NTPn have diverse genetic backgrounds and may have evolved as a distinct group of pneumococcal isolates.

scholarly journals Genomic Characteristics of Invasive Streptococcus pneumoniae Serotype 1 in New Caledonia Prior to the Introduction of PCV13

2020 ◽  
Vol 14 ◽  
pp. 117793222096210 ◽  
Author(s):  
Mariem Hanachi ◽  
Anmol Kiran ◽  
Jennifer Cornick ◽  
Emna Harigua-Souiai ◽  
Dean Everett ◽  
...  
Keyword(s):  
Population Structure ◽  
Streptococcus Pneumoniae ◽  
Virulence Genes ◽  
New Caledonia ◽  
Disease Outbreaks ◽  
Genomic Diversity ◽  
Whole Genome Sequence ◽  
Serotype 1 ◽  
The Impact ◽  
Sequence Types

Streptococcus pneumoniae serotype 1 is a common cause of global invasive pneumococcal disease. In New Caledonia, serotype 1 is the most prevalent serotype and led to two major outbreaks reported in the 2000s. The pneumococcal conjugate vaccine 13 (PCV13) was introduced into the vaccination routine, intending to prevent the expansion of serotype 1 in New Caledonia. Aiming to provide a baseline for monitoring the post-PCV13 changes, we performed a whole-genome sequence analysis on 67 serotype 1 isolates collected prior to the PCV13 introduction. To highlight the S. pneumoniae serotype 1 population structure, we performed a multilocus sequence typing (MLST) analysis revealing that NC serotype 1 consisted of 2 sequence types: ST3717 and the highly dominant ST306. Both sequence types harbored the same resistance genes to beta-lactams, macrolide, streptogramin B, fluoroquinolone, and lincosamide antibiotics. We have also identified 36 virulence genes that were ubiquitous to all the isolates. Among these virulence genes, the pneumolysin sequence presented an allelic profile associated with disease outbreaks and reduced hemolytic activity. Moreover, recombination hotspots were identified in 4 virulence genes and more notably in the cps locus ( cps2L), potentially leading to capsular switching, a major mechanism of the emergence of nonvaccine types. In summary, this study represents the first overview of the genomic characteristics of S. pneumoniae serotype 1 in New Caledonia prior to the introduction of PCV13. This preliminary description represents a baseline to assess the impact of PCV13 on serotype 1 population structure and genomic diversity.

scholarly journals Characterization of Streptococcus pneumoniae isolates from India with special reference to their sequence types

2013 ◽  
Vol 7 (02) ◽  
pp. 101-109 ◽  
Author(s):  
Malini Shariff ◽  
Jyoti Choudhary ◽  
Shazia Zahoor ◽  
Monorama Deb
Keyword(s):  
Streptococcus Pneumoniae ◽  
Multilocus Sequence Typing ◽  
Clonal Complex ◽  
The Elderly ◽  
New Delhi ◽  
Broth Microdilution ◽  
Mortality And Morbidity ◽  
Resistance To Penicillin ◽  
Sequence Types

Introduction: Streptococcus pneumoniae is a major cause of mortality and morbidity in young children and the elderly. In the present study we evaluated antimicrobial susceptibilities, serotypes, and sequence types of pneumococcal isolates recovered in New Delhi, India. Methodology: A total of 126 clinical isolates of Streptococcus pneumoniae were investigated. They were subjected to disk diffusion susceptibility testing, broth microdilution testing, serotyping and multilocus sequence typing. Results: Broth microdilution assay showed that 5%, 20% and 23% of the isolates exhibited resistance to penicillin, erythromycin and ciprofloxacin, respectively. Serotypes19, 1 and 6 were more frequently isolated. Thirty per cent of the strains were comprised of serotypes 1, 3, 5, 19A and 7F, which are not included in the seven-valent vaccine. Fifty-nine isolates were typed using multilocus sequence typing. Thirty new sequence types were encountered in this study. Only one clonal complex with 4 isolates was seen; 11 clonal complexes and 96 sequence types (STs) were observed among 115 Indian isolates. Only 18 of the 96 STs were found globally, of which only 4 STs were found in many countries with larger numbers. Conclusions: This study identifies the non-vaccine serotypes of Streptococcus pneumoniae circulating in India. It is important that an appropriate vaccine which covers all serotypes is used in the region.

scholarly journals Antibiotic Resistance and Molecular Biological Characteristics of Non-13-Valent-Pneumococcal Conjugate Vaccine Serogroup 15 Streptococcus pneumoniae Isolated From Children in China

2022 ◽  
Vol 12 ◽  
Author(s):  
Wei Shi ◽  
Qianqian Du ◽  
Lin Yuan ◽  
Wei Gao ◽  
Qing Wang ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Streptococcus Pneumoniae ◽  
Conjugate Vaccine ◽  
Pneumococcal Conjugate Vaccine ◽  
Resistance Rate ◽  
Diffusion Method ◽  
Molecular Characteristics ◽  
Quellung Reaction ◽  
Susceptibility Rate ◽  
Sequence Types

Background: The isolation rate of serogroup 15 Streptococcus pneumoniae has been increasing since developing countries began administering the 13-valent pneumococcal conjugate vaccine.Methods: We detected the antibiotic resistance and molecular characteristics of 126 serogroup 15 S. pneumoniae strains isolated from children in China. Serotypes were determined via the Quellung reaction. Antibiotic resistance was tested using the E-test or disc diffusion method. Sequence types were assigned via multilocus sequence typing. Data were analyzed using WHONET 5.6 software.Results: The frequencies of S. pneumoniae serotypes 15A, 15B, 15C, and 15F were 29.37, 40.48, 28.57, and 1.59%, respectively. Continuous-monitoring data from Beijing showed that the annual isolation rates of serogroup 15 S. pneumoniae were 7.64, 7.17, 2.58, 4.35, 3.85, 7.41, and 10.53%, respectively, from 2013 to 2019. All 126 serogroup 15 strains were susceptible to vancomycin and ceftriaxone. The non-susceptibility rate to penicillin was 78.57%. All strains were resistant to erythromycin with high minimum inhibitory concentrations (MICs). The multidrug resistance rate was 78.57%. The most common clonal complexes were CC3397, CC6011, CC10088, CC9785, and ST8589.Conclusion: Serogroup 15 S. pneumoniae is common among children in China, and these strains should be continuously monitored.

scholarly journals Molecular epidemiology of colonizing and disease-causing Klebsiella pneumoniae in paediatric patients

2014 ◽  
Vol 63 (4) ◽  
pp. 610-616 ◽  
Author(s):  
Malaika L. Little ◽  
Xuan Qin ◽  
Danielle M. Zerr ◽  
Scott J. Weissman
Keyword(s):  
Population Structure ◽  
Multidrug Resistance ◽  
Klebsiella Pneumoniae ◽  
Medical Condition ◽  
Relative Distribution ◽  
Paediatric Patients ◽  
Vitek 2 ◽  
Human Colonization ◽  
Sequence Types ◽  
Underlying Medical Condition

Klebsiella pneumoniae causes a range of clinical disease in paediatric patients and is of increasing concern due to growing antibiotic resistance, yet little is known about the relative distribution of commensal and pathogens throughout the population structure of K. pneumoniae. We conducted a prospective, observational study of 92 isolates from Seattle Children’s Hospital, including 49 disease isolates from blood and urine (13 and 36 isolates, respectively) and 43 colonization isolates from stool. Susceptibility to 20 antimicrobials was evaluated using disc diffusion, VITEK 2 and Etest. Strain relatedness was investigated using multilocus sequence typing (MLST). Demographic and clinical characteristics were largely similar between disease and colonization cohorts, with 85.7 and 74.4 % of disease and colonization cohort patients, respectively, having an underlying medical condition; the sole exception was a relative abundance of patients with urologic or renal abnormalities in the disease cohort, consistent with the predominance of urine specimens among the disease isolates. With regard to antibiotic susceptibility properties, no significant differences were noted between the disease and colonization cohorts. Using molecular analysis, 71 unique sequence types (STs) were distinguished, with novel MLST findings evident in both cohorts; 43 (46.7 %) isolates represented novel STs, including 22 with a novel allele sequence. Thirteen STs contained multiple isolates and all seven isolates with resistance to three or more antibiotic classes were within one of four multirepresentative STs. This study demonstrates that nearly half of paediatric Klebsiella isolates represent novel STs, with clustering of multidrug resistance within specific STs. These findings expand our understanding of the intersection of bacterial population structure, human colonization ecology and multidrug resistance in K. pneumoniae.

scholarly journals Susceptibilities to Levofloxacin in Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis Clinical Isolates from Children: Results from 2000-2001 and 2001-2002 TRUST Studies in the United States

2003 ◽  
Vol 47 (6) ◽  
pp. 1790-1797 ◽  
Author(s):  
James A. Karlowsky ◽  
Clyde Thornsberry ◽  
Ian A. Critchley ◽  
Mark E. Jones ◽  
Alan T. Evangelista ◽  
...  
Keyword(s):  
United States ◽  
Multidrug Resistance ◽  
Streptococcus Pneumoniae ◽  
Respiratory Tract ◽  
Moraxella Catarrhalis ◽  
Pediatric Patients ◽  
Respiratory Illness ◽  
The United States ◽  
Surveillance Studies ◽  
Resistance To Penicillin

ABSTRACT Among respiratory tract isolates of Streptococcus pneumoniae from children, resistance to penicillins, cephalosporins, macrolides, and trimethoprim-sulfamethoxazole (SXT) increases on an annual basis. Pediatric patients who do not respond to conventional therapy for respiratory tract infections someday may be treated with fluoroquinolones. In this study, MICs of β-lactams, azithromycin, SXT, and levofloxacin were determined and interpreted by using NCCLS guidelines for isolates of S. pneumoniae (2,834 from children and 10,966 from adults), Haemophilus influenzae (629 from children and 2,281 from adults), and Moraxella catarrhalis (389 from children and 1,357 from adults) collected during the 2000-2001 and 2001-2002 respiratory illness seasons in the United States as part of the ongoing TRUST surveillance studies. Rates of resistance to penicillin, azithromycin, and SXT were ≥7.5% higher among patients ≤4 years old than among patients 5 to 10, 11 to 17, and ≥18 years old in both the 2000-2001 and the 2001-2002 respiratory illness seasons. Levofloxacin resistance was detected in 2 of 2,834 isolates (0.07%) from patients <18 years old. Levofloxacin MICs of 0.25 to 1 μg/ml accounted for 99.6, 99.5, 99.3, 99.7, 98.4, and 98.0% of isolates from patients <2, 2 to 4, 5 to 10, 11 to 17, 18 to 64, and >64 years old. Multidrug resistance was twice as common among patients ≤4 years old (25.3%) as among patients 5 to 10 years old (13.7%), 11 to 17 years old (11.9%), 18 to 64 years old (12.1%), and >64 years old (12.4%). The most common multidrug resistance phenotype in S. pneumoniae isolates for all age groups was resistance to penicillin, azithromycin, and SXT (70.3 to 76.6%). For H. influenzae and M. catarrhalis isolates from patients <2, 2 to 4, 5 to 10, 11 to 17, 18 to 64, and >64 years old, levofloxacin MICs at which 90% of the isolates were inhibited were 0.015 and 0.03 to 0.06 μg/ml, respectively, in the 2000-2001 and 2001-2002 respiratory illness seasons. In the 2000-2001 and 2001-2002 respiratory illness season surveillance studies in the United States, 99.9% of pediatric isolates of S. pneumoniae were susceptible to levofloxacin. If fluoroquinolones become a treatment option for pediatric patients, careful monitoring of fluoroquinolone susceptibilities will be increasingly important in future surveillance studies.

scholarly journals 133. The Changing Phenotypes and Genotypes of Invasive Pneumococcal Isolates From Children in Shenzhen During 2013–2017

2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S95-S95
Author(s):  
Yanmin Bao ◽  
Yuejie Zheng
Keyword(s):  
Antibiotic Resistance ◽  
Streptococcus Pneumoniae ◽  
Minimum Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
The Other ◽  
Significant Difference ◽  
Ermb Gene ◽  
Resistance To Penicillin ◽  
Resistance Rates ◽  
Sequence Types

Abstract Background The phenotypes and genotypes of Streptococcus pneumoniae (Spn.) isolated from children with invasive pneumococcal diseases (IPDs) were changed in these years. The purpose of this study was to monitor this mutation trends before the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in China. Methods Strains were isolated from children less than 14 years old between January 2013 and May 2017 in Shenzhen Children’s Hospital. Serotypes, antibiotic resistance, and genotypes of these isolates were determined using capsular swelling, E-test, and multi-locus sequence typing, respectively. Results A total of 94 Spn. strains were isolated, which belonged to 15 serotypes. The five most prevalent serotypes were 19F (25.5%), 19A (19%), 14 (17%), 23F (7.5%), and 6B (9.6%). The other two serotypes (19C and 15) were non-vaccine types. We found 42 sequence types (STs) for these isolates. The most abundant STs were ST271 (24.4%), ST876 (17%), and ST320 (10.6%), mainly related to 19F, 14, and 19A, respectively. The potential coverage of PCV13 was 87.2%. Among non-meningitis isolates, the resistance rates to penicillin and ceftriaxone were 0% and 2%. However, the meningitis isolates showed universal resistance to penicillin (80%) and ceftriaxone (20%). Most of these isolates (95.7%) were resistant to erythromycin, and 66 (70.2%) strains carried the ermB gene and 24 (25.5%) strains carried both the ermB and mefA/E genes. Serotype 19A showed the highest minimum inhibitory concentration (MIC) for penicillin than the other serotypes, but no significant difference in penicillin MIC among the three main STs (ST271, ST320, and ST876). Conclusion The phenotypes and genotypes of invasive pneumococcal isolates from children in Shenzhen have changed with the passage of time. Compared with PCV7, PCV13 can more effectively protect Chinese children from IPDs. To some extent, these changes are possibly related to the usage of antibiotics and vaccines. Disclosures All authors: No reported disclosures.

scholarly journals Multiple clonal types of nonvaccine serotypes constitute β-lactams nonsusceptible pneumococcus isolates from adult pneumonia patients in Japan

2021 ◽  
Author(s):  
Satoshi Kakiuchi ◽  
Bhim Gopal Dhoubhadel ◽  
Motoi Suzuki ◽  
Tomoko Ishifuji ◽  
Kiwao Watanabe ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Antimicrobial Susceptibility ◽  
Polysaccharide Vaccine ◽  
Dilution Method ◽  
Agar Dilution Method ◽  
Pneumococcal Polysaccharide Vaccine ◽  
Global Spread ◽  
Agar Dilution ◽  
Quellung Reaction ◽  
Sequence Types

Abstract Background and objective The global spread of antimicrobial-nonsusceptible Streptococcus pneumoniae is a major concern. Molecular epidemiology of those strains in relation to vaccine serotype remains to be explored in Japan. This study aimed to elucidate the distribution of molecular types with the serotypes and antimicrobial susceptibility of pneumococcus strains isolated from adult pneumonia patients. Methods We enrolled adult pneumonia patients from four sites in Japan between September 2011 and August 2014. S. pneumoniae isolates from sputum and blood were analyzed for serotyping by the Quellung reaction and for antimicrobial susceptibility by the agar dilution method and e-test and for multilocus sequence typing. Results In total, 204 isolates were analyzed from 200 patients with a median age of 72.5 years, of whom 55 (27.5%) patients had received a 23-valent pneumococcal polysaccharide vaccine (PPSV23). We detected 41 clonal complexes (CCs) and 62 sequence types (STs), including 10 new STs: CC/ST 180 of serotype 3 was the most common followed by CC/ST 236 of serotype 19F and CC/ST 99 of serotype 11A; 144 (70.6%) isolates were PPSV23 serotypes; 40 (19.6%) and 121 (59.3%) isolates were b-lactam nonsusceptible (bNS) and multidrug-nonsusceptible strains, respectively. Among the bNS strains, 18 (45%) were nonvaccine serotypes, and 4 CCs (CC236, CC63, CC242, and CC558) comprised of 62.5% of them.Conclusion Multiple CCs of bNS strains, including nonvaccine serotype are spreading. It is crucial to monitor the antimicrobial susceptibility, serotypes, and molecular types of pneumococci to predict the effectiveness of vaccines in preventing pneumonia by bNS pneumococci strains.

scholarly journals Antimicrobial resistance profile and multidrug resistance patterns of Streptococcus pneumoniae isolates from patients suspected of pneumococcal infections in Ethiopia

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Bekele Sharew ◽  
Feleke Moges ◽  
Gizachew Yismaw ◽  
Wondwossen Abebe ◽  
Surafal Fentaw ◽  
...  
Keyword(s):  
Multidrug Resistance ◽  
Streptococcus Pneumoniae ◽  
Antimicrobial Resistance ◽  
Addis Ababa ◽  
Pneumococcal Infection ◽  
Test Method ◽  
Resistance Testing ◽  
Global Public Health ◽  
Pneumococcal Infections ◽  
Resistance Patterns

Abstract Background Antimicrobial-resistant strains of Streptococcus pneumoniae have become one of the greatest challenges to global public health today and inappropriate use of antibiotics and high level of antibiotic use is probably the main factor driving the emergence of resistance worldwide. The aim of this study is, therefore, to assess the antimicrobial resistance profiles and multidrug resistance patterns of S. pneumoniae isolates from patients suspected of pneumococcal infections in Ethiopia. Methods A hospital-based prospective study was conducted from January 2018 to December 2019 at Addis Ababa city and Amhara National Region State Referral Hospitals. Antimicrobial resistance tests were performed from isolates of S. pneumoniae that were collected from pediatric and adult patients. Samples (cerebrospinal fluid, blood, sputum, eye discharge, ear discharge, and pleural and peritoneal fluids) from all collection sites were initially cultured on 5% sheep blood agar plates and incubated overnight at 37 °C in a 5% CO2 atmosphere. Streptococcus pneumoniae was identified and confirmed by typical colony morphology, alpha-hemolysis, Gram staining, optochin susceptibility, and bile solubility test. Drug resistance testing was performed using the E-test method according to recommendations of the Clinical and Laboratory Standards Institute. Results Of the 57 isolates, 17.5% were fully resistant to penicillin. The corresponding value for both cefotaxime and ceftriaxone was 1.8%. Resistance rates to erythromycin, clindamycin, tetracycline, chloramphenicol and trimethoprim-sulfamethoxazole were 59.6%, 17.5%, 38.6%, 17.5 and 24.6%, respectively. Multidrug resistance (MDR) was seen in 33.3% isolates. The most common pattern was co-resistance to penicillin, erythromycin, clindamycin, and tetracycline. Conclusions Most S. pneumoniae isolates were susceptible to ceftriaxone and cefotaxime. Penicillin has been used as a drug of choice for treating S. pneumoniae infection. However, antimicrobial resistance including multidrug resistance was observed to several commonly used antibiotics including penicillin. Hence, it is important to periodically monitor the antimicrobial resistance patterns to select empirical treatments for better management of pneumococcal infection.

scholarly journals Need for Annual Surveillance of Antimicrobial Resistance in Streptococcus pneumoniae in the United States: 2-Year Longitudinal Analysis

2001 ◽  
Vol 45 (4) ◽  
pp. 1037-1042 ◽  
Author(s):  
Daniel F. Sahm ◽  
James A. Karlowsky ◽  
Laurie J. Kelly ◽  
Ian A. Critchley ◽  
Mark E. Jones ◽  
...  
Keyword(s):  
United States ◽  
Streptococcus Pneumoniae ◽  
Antimicrobial Resistance ◽  
Antimicrobial Agents ◽  
The United States ◽  
Multidrug Resistant ◽  
Fluoroquinolone Resistance ◽  
Resistance Patterns ◽  
Changing Patterns ◽  
Resistance To Penicillin

ABSTRACT Although changing patterns in antimicrobial resistance inStreptococcus pneumoniae have prompted several surveillance initiatives in recent years, the frequency with which these studies are needed has not been addressed. To approach this issue, the extent to which resistance patterns change over a 1-year period was examined. In this study we analyzed S. pneumoniaeantimicrobial susceptibility results produced in our laboratory with isolates obtained over 2 consecutive years (1997–1998 and 1998–1999) from the same 96 institutions distributed throughout the United States. Comparison of results revealed increases in resistant percentages for all antimicrobial agents studied except vancomycin. For four of the agents tested (penicillin, cefuroxime, trimethoprim-sulfamethoxazole, and levofloxacin), the increases were statistically significant (P < 0.05). Resistance to the fluoroquinolone remained low in both years (0.1 and 0.6%, respectively); in contrast, resistance to macrolides was consistently greater than 20%, and resistance to trimethoprim-sulfamethoxazole increased from 13.3 to 27.3%. Multidrug resistance, concurrent resistance to three or more antimicrobials of different chemical classes, also increased significantly between years, from 5.9 to 11%. The most prevalent phenotype was resistance to penicillin, azithromycin (representative macrolide), and trimethoprim-sulfamethoxazole. Multidrug-resistant phenotypes that included fluoroquinolone resistance were uncommon; however, two phenotypes that included fluoroquinolone resistance not found in 1997–1998 were encountered in 1998–1999. This longitudinal surveillance study of resistance inS. pneumoniae revealed that significant changes do occur in just a single year and supports the need for surveillance at least on an annual basis, if not continuously.

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