Decline and Rise of the Antimicrobial Susceptibility of Streptococcus pneumoniae Isolated from Middle Ear Fluid in Children: Influence of Changes in Circulating Serotypes

ABSTRACTChanges in the antimicrobial susceptibility ofStreptococcus pneumoniaecausing otitis media were studied in 916 isolates from children <5 years old between 1999 and 2010 in a region of northern Spain. The rate of antimicrobial resistance decreased between the period before the introduction of the heptavalent pneumococcal conjugate vaccine (from 1999 to 2001) and the period from 2005 to 2007. However, in 2008 to 2010, resistance rates increased again due to the spread of serotype 19A, especially the multidrug-resistant ST320 and ST276 clones.

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Acute Mastoiditis in the Pneumococcal Conjugate Vaccine Era

Clinical and Vaccine Immunology ◽

10.1128/cvi.00289-14 ◽

2014 ◽

Vol 21 (8) ◽

pp. 1189-1191 ◽

Cited By ~ 14

Author(s):

Sharon Ovnat Tamir ◽

Yehudah Roth ◽

Ilan Dalal ◽

Abraham Goldfarb ◽

Tal Marom

Keyword(s):

Streptococcus Pneumoniae ◽

Middle Ear ◽

Pneumococcal Conjugate Vaccine ◽

Inverse Relationship ◽

Acute Otitis Media ◽

Acute Mastoiditis ◽

Conjugate Vaccines ◽

Content Type ◽

Bacterial Cultures ◽

Middle Ear Fluid

ABSTRACTFollowing the introduction of the 7- and 13-valent pneumococcal conjugate vaccines, we observed an inverse relationship between the increasing rate of immunized children and the proportion of middle ear fluid cultures collected during acute mastoiditis episodes that tested positive forStreptococcus pneumoniaeamong a subset of children 0 to 6 years old who had initially presented with severe acute otitis media and had bacterial cultures collected during tympanocentesis or from spontaneous otorrhea.

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Prevalence of Cefotaxime-Resistant Escherichia coli Isolates from Healthy Cattle and Sheep in Northern Spain: Phenotypic and Genome-Based Characterization of Antimicrobial Susceptibility

Applied and Environmental Microbiology ◽

10.1128/aem.00742-20 ◽

2020 ◽

Vol 86 (15) ◽

Cited By ~ 1

Author(s):

Maitane Tello ◽

Medelin Ocejo ◽

Beatriz Oporto ◽

Ana Hurtado

Keyword(s):

Antimicrobial Resistance ◽

Resistance Genes ◽

Antimicrobial Susceptibility ◽

Basque Country ◽

Northern Spain ◽

Content Type ◽

E Coli ◽

Extended Spectrum ◽

Cattle Herds ◽

Cattle And Sheep

ABSTRACT In order to estimate herd-level prevalence of extended-spectrum β-lactamase/AmpC β-lactamase (ESBL/AmpC)- and carbapenemase-producing commensal Escherichia coli in ruminants in the Basque Country (northern Spain), a cross-sectional survey was conducted in 2014 to 2016 in 300 herds using selective isolation. ESBL-/AmpC-producing E. coli was isolated in 32.9% of dairy cattle herds, 9.6% of beef cattle herds, and 7.0% of sheep flocks. No carbapenemase-producing E. coli was isolated. Phenotypic antimicrobial susceptibility determined by broth microdilution using EUCAST epidemiological cutoff values identified widespread coresistance to extended-spectrum cephalosporins and other antimicrobials (110/135 isolates), particularly tetracycline, sulfamethoxazole, trimethoprim, and ciprofloxacin. All isolates were susceptible to tigecycline, imipenem, meropenem, and colistin. The genomes of 66 isolates were sequenced using an Illumina NovaSeq 6000 and screened for antimicrobial resistance determinants against ResFinder and PointFinder. The plasmid/chromosomal locations of resistance genes were predicted with PlasFlow, and plasmid replicons were identified using PlasmidFinder. Fifty-two acquired resistance genes and point mutations in another four genes that coded for resistance to 11 antimicrobial classes were identified. Fifty-five genomes carried ESBL-encoding genes, blaCTX-M-14 being the most common, and 11 carried determinants of the AmpC phenotype, mostly the blaCMY-2 gene. Additionally, genes coding for β-lactamases of the CTX-M group 9 were detected as well as the sporadic presence of blaSHV-12, blaCMY-4, and a point mutation in the ampC promoter. Only a bovine isolate coharbored more than one ESBL/AmpC genetic determinant (blaCTX-M-14 and a mutation in the ampC promoter), confirming its ESBL- and AmpC β-lactamase-producing phenotype. Most ESBL/AmpC genes were located in IncI1 plasmids, which also carried a great variety of other antimicrobial resistance genes. IMPORTANCE Extended-spectrum β-lactamase (ESBL)- and AmpC β-lactamase (AmpC)-producing E. coli isolates have emerged in recent years as some of the fastest spreading antimicrobial resistance determinants in humans and food-producing animals, becoming a concern for animal and public health. This study provided insight into the prevalence of cefotaxime-resistant E. coli in cattle and sheep in the Basque Country and the associated genetic determinants of antimicrobial resistance. These constituted an important contribution to the limited repository of such data for cattle in the region and for sheep worldwide. Antimicrobial susceptibility testing by phenotypic and molecular methods is key in surveillance programs to enhance early detection of resistance development, monitor resistance trends, and provide guidance to clinicians in selecting the adequate therapy.

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Antimicrobial Susceptibility and Clonality of Vaginally Derived Multidrug-Resistant Mobiluncus Isolates in China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00780-20 ◽

2020 ◽

Vol 64 (8) ◽

Author(s):

Xueying Zhang ◽

Yongying Bai ◽

Long Zhang ◽

Mohamed S. Draz ◽

Zhi Ruan ◽

...

Keyword(s):

Phylogenetic Analysis ◽

Antimicrobial Resistance ◽

Transposable Element ◽

Genome Sequencing ◽

Antimicrobial Susceptibility ◽

Multidrug Resistant ◽

Resistance Mechanisms ◽

Whole Genome ◽

Content Type ◽

High Diversity

ABSTRACT Here, the antimicrobial susceptibility, resistance mechanisms, and clonality of Mobiluncus sp. isolates recovered from gynecological outpatients in China were investigated. Compared to M. mulieris, M. curtisii exhibited higher antimicrobial resistance to metronidazole, clindamycin, and tetracycline. Whole-genome sequencing indicated that the clindamycin resistance gene erm(X) was located on a transposable element, Tn5432, which was composed of two IS1249 sequences. Phylogenetic analysis indicated that Mobiluncus spp. had high diversity, with isolates being grouped into several sporadic clades.

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Efficacy of Solithromycin (CEM-101) for Experimental Otitis Media Caused by Nontypeable Haemophilus influenzae and Streptococcus pneumoniae

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00863-16 ◽

2016 ◽

Vol 60 (9) ◽

pp. 5533-5538 ◽

Cited By ~ 3

Author(s):

M. Figueira ◽

P. Fernandes ◽

S. I. Pelton

Keyword(s):

Streptococcus Pneumoniae ◽

Haemophilus Influenzae ◽

Otitis Media ◽

Middle Ear ◽

Fourth Generation ◽

Minimal Bactericidal Concentration ◽

Nontypeable Haemophilus Influenzae ◽

Time Curve ◽

Content Type ◽

Middle Ear Fluid

ABSTRACTSolithromycin (CEM-101) is a “fourth-generation” macrolide, as it has three binding site and is acid stable. The three binding sites confer activity against bacteria resistant to the older macrolides and ketolides, including multidrug-resistantStreptococcus pneumoniaeand nontypeableHaemophilus influenzae(NTHi). The objective of this study was to evaluate solithromycin pharmacokinetics (PK), middle ear fluid (MEF) concentrations, and microbiologic efficacy in a chinchilla model of experimental otitis media (EOM) due to strains ofS. pneumoniaeor NTHi. Plasma PK (maximum concentration of drug in serum [Cmax] and area under the concentration-time curve from 0 to 24 h [AUC0–24]) and middle ear fluid (MEF) concentrations were determined. Isolates with specified antimicrobial susceptibility patterns were inoculated directly into the middle ear (ME). Plasma and MEF were collected for PK and MEF cultures performed to determine efficacy. Solithromycin administered at 150 mg/kg of body weight/day resulted inCmaxand AUC0–24values of 2.2 μg/ml and 27.4 μg · h/ml in plasma and 1.7 μg/ml and 28.2 μg · h/ml in extracellular MEF on day 1. By day 3,Cmaxand AUC0–24values had increased to 4.5 μg/ml and 54 μg · h/ml in plasma and 4.8 μg/ml and 98.6 μg · h/ml in extracellular MEF. For NTHi EOM, three isolates with MIC/minimal bactericidal concentration (MBC) ratios of 0.5/1 μg/ml (isolate BCH1), 2/2 μg/ml (isolate BMC1247C), and 4/4 μg/ml (isolate BMC1213C) were selected. The MEF of >85% of animals infected with BCH1 and BMC1247C was sterilized. For NTHi BMC1213, >85% of MEF cultures remained positive. ForS. pneumoniaeEOM, 3 isolates with MIC/MBC ratios of 0.06/0.125 μg/ml (S. pneumoniae331), 0.125/1 μg/ml (S. pneumoniaeCP-645 [MLSBphenotype]), and 0.5/2 μg/ml (CP-712 [mefAsubclassmefAresistance]) were selected. Solithromycin sterilized MEF in 100% of animals infected withS. pneumoniae331 andS. pneumoniaeCP-645. ME infection persisted in 60% of animals infected with CP-712. In a model of EOM, solithromycin sterilized MEF in >85% of animals challenged with NTHi with an MIC of ≤2 μg/ml and 100% of ME infected withS. pneumoniaewith an MIC of ≤0.125 μg/ml.

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Changing Trends in Antimicrobial Resistance and Serotypes of Streptococcus pneumoniae Isolates in Asian Countries: an Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.05658-11 ◽

2012 ◽

Vol 56 (3) ◽

pp. 1418-1426 ◽

Cited By ~ 207

Author(s):

So Hyun Kim ◽

Jae-Hoon Song ◽

Doo Ryeon Chung ◽

Visanu Thamlikitkul ◽

Yonghong Yang ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Antimicrobial Resistance ◽

Asian Countries ◽

Erythromycin Resistance ◽

Pneumococcal Infections ◽

Prospective Surveillance ◽

Content Type ◽

Changing Trends ◽

High Prevalence ◽

Heptavalent Pneumococcal Conjugate Vaccine

ABSTRACTAntimicrobial resistance inStreptococcus pneumoniaeremains a serious concern worldwide, particularly in Asian countries, despite the introduction of heptavalent pneumococcal conjugate vaccine (PCV7). The Asian Network for Surveillance of Resistant Pathogens (ANSORP) performed a prospective surveillance study of 2,184S. pneumoniaeisolates collected from patients with pneumococcal infections from 60 hospitals in 11 Asian countries from 2008 to 2009. Among nonmeningeal isolates, the prevalence rate of penicillin-nonsusceptible pneumococci (MIC, ≥4 μg/ml) was 4.6% and penicillin resistance (MIC, ≥8 μg/ml) was extremely rare (0.7%). Resistance to erythromycin was very prevalent in the region (72.7%); the highest rates were in China (96.4%), Taiwan (84.9%), and Vietnam (80.7%). Multidrug resistance (MDR) was observed in 59.3% of isolates from Asian countries. Major serotypes were 19F (23.5%), 23F (10.0%), 19A (8.2%), 14 (7.3%), and 6B (7.3%). Overall, 52.5% of isolates showed PCV7 serotypes, ranging from 16.1% in Philippines to 75.1% in Vietnam. Serotypes 19A (8.2%), 3 (6.2%), and 6A (4.2%) were the most prominent non-PCV7 serotypes in the Asian region. Among isolates with serotype 19A, 86.0% and 79.8% showed erythromycin resistance and MDR, respectively. The most remarkable findings about the epidemiology ofS. pneumoniaein Asian countries after the introduction of PCV7 were the high prevalence of macrolide resistance and MDR and distinctive increases in serotype 19A.

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Prevalence and antimicrobial susceptibility of Salmonella in Japanese broiler flocks

Epidemiology and Infection ◽

10.1017/s0950268812000039 ◽

2012 ◽

Vol 140 (11) ◽

pp. 2074-2081 ◽

Cited By ~ 18

Author(s):

Y. SASAKI ◽

A. IKEDA ◽

K. ISHIKAWA ◽

M. MURAKAMI ◽

M. KUSUKAWA ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Antimicrobial Susceptibility ◽

Antimicrobial Agents ◽

Multidrug Resistant ◽

Resistance Rates

SUMMARYThis study determined the prevalence and antimicrobial susceptibility of Salmonella isolated from broiler flocks in Japan. Caecal dropping samples were collected from 288 broiler flocks between November 2007 and February 2010. Salmonella was prevalent in 248 (86·1%) broiler flocks. The top three serovars were S. Infantis, S. Manhattan and S. Schwarzengrund. S. Infantis was found in all regions tested in this study. However, S. Manhattan and S. Schwarzengrund were frequently found only in the western part of Japan. High antimicrobial resistance rates were observed against oxytetracycline (90·2%), dihydrostreptomycin (86·7%) and ampicillin (36·5%), and 258 (90·5%) of 285 isolates were resistant to two or more antimicrobial agents. Interestingly, 26·3% of isolates were resistant to ceftiofur, especially 38·1% of S. Infantis isolates, although its use in broilers has not been approved in Japan. This study showed that Salmonella is highly prevalent (86·1%) in Japanese broiler flocks, that 90·5% of Salmonella isolates were multidrug-resistant, and that S. Infantis frequently exhibited resistance to cephalosporin antimicrobial agents.

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Antimicrobial Resistance among Clinical Isolates of Streptococcus pneumoniae in Canada during 2000

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.46.5.1295-1301.2002 ◽

2002 ◽

Vol 46 (5) ◽

pp. 1295-1301 ◽

Cited By ~ 69

Author(s):

Donald E. Low ◽

Joyce de Azavedo ◽

Karl Weiss ◽

Tony Mazzulli ◽

Magdalena Kuhn ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Antimicrobial Resistance ◽

Respiratory Tract ◽

Lower Respiratory Tract ◽

Antimicrobial Agents ◽

Multidrug Resistant ◽

Clinical Isolates ◽

Central Laboratory ◽

Resistant Strains ◽

Resistance Rates

ABSTRACT A total of 2,245 clinical isolates of Streptococcus pneumoniae were collected from 63 microbiology laboratories from across Canada during 2000 and characterized at a central laboratory. Of these isolates, 12.4% were not susceptible to penicillin (penicillin MIC, ≥0.12 μg/ml) and 5.8% were resistant (MIC, ≥2 μg/ml). Resistance rates among non-β-lactam agents were the following: macrolides, 11.1%; clindamycin, 5.7%; chloramphenicol, 2.2%; levofloxacin, 0.9%; gatifloxacin, 0.8%; moxifloxacin, 0.4%; and trimethoprim-sulfamethoxazole, 11.3%. The MICs at which 90% of the isolates were inhibited (MIC90s) of the fluoroquinolones were the following: gemifloxacin, 0.03 μg/ml; BMS-284756, 0.06 μg/ml; moxifloxacin, 0.12 μg/ml; gatifloxacin, 0.25 μg/ml; levofloxacin, 1 μg/ml; and ciprofloxacin, 1 μg/ml. Of 578 isolates from the lower respiratory tract, 21 (3.6%) were inhibited at ciprofloxacin MICs of ≥4 μg/ml. None of the 768 isolates from children were inhibited at ciprofloxacin MICs of ≥4 μg/ml, compared to 3 of 731 (0.6%) from those ages 15 to 64 (all of these >60 years old), and 27 of 707 (3.8%) from those over 65. The MIC90s for ABT-773 and telithromycin were 0.015 μg/ml for macrolide-susceptible isolates and 0.12 and 0.5 μg/ml, respectively, for macrolide-resistant isolates. The MIC of linezolid was ≤2 μg/ml for all isolates. Many of the new antimicrobial agents tested in this study appear to have potential for the treatment of multidrug-resistant strains of pneumococci.

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Population genetic structure, serotype distribution and antibiotic resistance of Streptococcus pneumoniae causing invasive disease in children in Argentina

Microbial Genomics ◽

10.1099/mgen.0.000636 ◽

2021 ◽

Vol 7 (9) ◽

Author(s):

Paula Gagetti ◽

Stephanie W. Lo ◽

Paulina A. Hawkins ◽

Rebecca A. Gladstone ◽

Mabel Regueira ◽

...

Keyword(s):

Streptococcus Pneumoniae ◽

Antimicrobial Resistance ◽

Type Species ◽

Invasive Disease ◽

Multidrug Resistant ◽

Childhood Immunization ◽

Content Type ◽

Sequencing Project ◽

Link Type ◽

Immunization Programme

Invasive disease caused by Streptococcus pneumoniae (IPD) is one of the leading causes of morbidity and mortality in young children worldwide. In Argentina, PCV13 was introduced into the childhood immunization programme nationwide in 2012 and PCV7 was available from 2000, but only in the private market. Since 1993 the National IPD Surveillance Programme, consisting of 150 hospitals, has conducted nationwide pneumococcal surveillance in Argentina in children under 6 years of age, as part of the SIREVA II-OPS network. A total of 1713 pneumococcal isolates characterized by serotype (Quellung) and antimicrobial resistance (agar dilution) to ten antibiotics, belonging to three study periods: pre-PCV7 era 1998–1999 (pre-PCV), before the introduction of PCV13 2010–2011 (PCV7) and after the introduction of PCV13 2012–2013 (PCV13), were available for inclusion. Fifty-four serotypes were identified in the entire collection and serotypes 14, 5 and 1 represented 50 % of the isolates. Resistance to penicillin was 34.9 %, cefotaxime 10.6 %, meropenem 4.9 %, cotrimoxazole 45 %, erythromycin 21.5 %, tetracycline 15.4 % and chloramphenicol 0.4 %. All the isolates were susceptible to levofloxacin, rifampin and vancomycin. Of 1713 isolates, 1061 (61.9 %) were non-susceptible to at least one antibiotic and 235(13.7 %) were multidrug resistant. A subset of 413 isolates was randomly selected and whole-genome sequenced as part of Global Pneumococcal Sequencing Project (GPS). The genome data was used to investigate the population structure of S. pneumoniae defining pneumococcal lineages using Global Pneumococcal Sequence Clusters (GPSCs), sequence types (STs) and clonal complexes (CCs), prevalent serotypes and their associated pneumococcal lineages and genomic inference of antimicrobial resistance. The collection showed a great diversity of strains. Among the 413 isolates, 73 known and 36 new STs were identified belonging to 38 CCs and 25 singletons, grouped into 52 GPSCs. Important changes were observed among vaccine types when pre-PCV and PCV13 periods were compared; a significant decrease in serotypes 14, 6B and 19F and a significant increase in 7F and 3. Among non-PCV13 types, serogroup 24 increased from 0 % in pre-PCV to 3.2 % in the PCV13 period. Our analysis showed that 66.1 % (273/413) of the isolates were predicted to be non-susceptible to at least one antibiotic and 11.9 % (49/413) were multidrug resistant. We found an agreement of 100 % when comparing the serotype determined by Quellung and WGS-based serotyping and 98.4 % of agreement in antimicrobial resistance. Continued surveillance of the pneumococcal population is needed to reveal the dynamics of pneumococcal isolates in Argentina in post-PCV13. This article contains data hosted by Microreact.

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Changes in serotype prevalence and antimicrobial resistance among invasive Streptococcus pneumoniae isolates in Korea, 1996–2008

Journal of Medical Microbiology ◽

10.1099/jmm.0.058164-0 ◽

2013 ◽

Vol 62 (8) ◽

pp. 1204-1210 ◽

Cited By ~ 19

Author(s):

Sungkyoung Lee ◽

Songmee Bae ◽

Kwang-Jun Lee ◽

Jae-Yon Yu ◽

Yeonho Kang

Keyword(s):

Streptococcus Pneumoniae ◽

Antimicrobial Resistance ◽

High Resistance ◽

Age Groups ◽

Pneumococcal Vaccination ◽

Multidrug Resistant ◽

Increasing Trend ◽

Resistance Rates ◽

Child Vaccination ◽

Over Time

We investigated changes in serotypes and antimicrobial susceptibilities among 386 isolates of invasive Streptococcus pneumoniae collected from numerous hospitals in Korea from 1996 to 2008. Serotypes 19F (9.8 %), 23F (8.3 %), 19A (7.8 %), 6A (7.5 %), 3 (7.3 %), 9V (6.5 %), 6B (6.2 %), 14 (4.9 %), 1 (3.9 %), 11A (3.9 %) and 4 (3.1 %) represented 69.2 % of all isolates. While the overall proportion of PCV7 serotypes was stable over time, we observed modest decreases in children <5 years old and in adults ≥65 years old between 1996–1999 and 2007–2008. An increased prevalence of non-PCV7 serotypes in these age groups was primarily attributable to an increase in serotypes 3, 6A and 19A. Most invasive S. pneumoniae isolates showed high resistance rates to erythromycin (74.9 %), tetracycline (71.1 %) and clindamycin (61.7 %). Between 1996–2003 and 2004–2008, non-susceptibility rates to cefotaxime and multi-drugs (three or more classes) in PCV7 serotypes showed a declining trend, while in non-PCV7 serotypes there was an increasing trend. Non-PCV7 serotypes 6A and 19A, which mostly exhibited multidrug-resistant phenotypes (69.0 % and 76.7 % respectively), increased between 1996–2003 and 2004–2008. Although PCV7 was introduced in Korea in November 2003, pneumococcal vaccination has not been included in the national child vaccination programme. Our results provide details of serotype occurrence that will be useful when adoption of universal pneumococcal vaccination in Korea is being considered.

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