Isolates Of Serotype Research Articles

Isolation and complete genome analysis of neurotropic dengue virus serotype 3 from the cerebrospinal fluid of an encephalitis patient.

Although neurological manifestations associated with dengue viruses (DENV) infection have been reported, there is very limited information on the genetic characteristics of neurotropic DENV. Here we describe the isolation and complete genome analysis of DENV serotype 3 (DENV-3) from cerebrospinal fluid of an encephalitis paediatric patient in Jakarta, Indonesia. Next-generation sequencing was employed to deduce the complete genome of the neurotropic DENV-3 isolate. Based on complete genome analysis, two unique and nine uncommon amino acid changes in the protein coding region were observed in the virus. A phylogenetic tree and molecular clock analysis revealed that the neurotropic virus was a member of Sumatran-Javan clade of DENV-3 genotype I and shared a common ancestor with other isolates from Jakarta around 1998. This is the first report of neurotropic DENV-3 complete genome analysis, providing detailed information on the genetic characteristics of this virus.

The existence of Listeria monocytogenes in a cattle slaughterhouse and identification of serotypes by mPCR

This study was carried out to investigate the presence of Listeria monocytogenes in samples obtained from a slaughterhouse in Samsun, Turkey. A total of 300 samples (25 samples per month) analyzed by Immunomagnetic Separation (IMS) based on conventional culture method. Then isolates were verified and serotyped by PCR using specific primers. According to the analysis, a total of 18 isolates were identified as L. monocytogenes. Distribution of these isolates were as; 5 isolates (serotype 1/2b or 3b) from 1 cattle carcass, 5 isolates (serotype 1/2b or 3b) from 1 knife, 2 isolates (serotype 4b or 4d, 4e) from 1 knife sharpener, 5 isolates (serotype 1/2a or 3a) from 1 floor sample, 1 isolate (serotype 1/2a or 3a) from 1 cowhide, respectively. As a result, carcasses are considered to pose a hazard to public health due to L. monocytogenes contamination. The development of slaughterhouse conditions and production technology, improving the education level of employees in food safety issues, prevention of contamination of foodborne pathogens to carcasses in slaughterhouses and implementation of effective sanitation methods should be provided

Invasive Disease Caused Simultaneously by Dual Serotypes of Streptococcus pneumoniae.

There are at least 98 known pneumococcal serotypes. Invasive pneumococcal disease (IPD) is usually caused by a single serotype, and dual-serotype IPD is rare. To assess factors associated with dual-serotype IPD, patient information obtained through laboratory-based surveillance for IPD from 2005 through 2014 in South Africa was reviewed. Genomes of isolate pairs from coinfected individuals were sequenced to determine their molecular characteristics. For 30 (91%) of 33 patients with dual serotypes, one or both isolates were a pneumococcal conjugate vaccine (PCV13) serotype. Dual-serotype IPD was associated with children <5 years of age (adjusted odds ratio [aOR], 4.7; 95% confidence interval [95% CI], 1.8 to 11.7), underlying illness (other than HIV) (aOR, 2.8; 95% CI, 1.1 to 6.6) and death (aOR, 2.5; 95% CI, 1.08 to 6.09). For each coinfecting pair, isolates were genotypically unrelated, and their genotypes were common among isolates of the same serotype in South Africa. Of 701 accessory genes identified among dual-serotype IPD isolates, four were common between isolate pairs. Coinfecting isolate pairs had different genotypic backgrounds. The association of dual serotypes with death warrants increased awareness of IPD coinfection caused by two or more serotypes.

Prevalence of Listeria monocytogenes in cerebrospinal fluid obtained from hospitalized patients

The aim of the present study was to determine the occurrence of Listeria monocytogenes in cerebrospinal fluid (CSF) samples obtained from patients with meningitis symptoms. A total of 102 CSF samples which were referred for bacterial culture to microbiology laboratory in Mashhad’s Hospital were included in this study. All of the samples were cultured and positive ones confirmed by multiplex-PCR. Molecular serotyping and virulence characterization of isolates were performed. Random amplified polymorphic DNA-PCR using three set of primers was performed for evaluation of genetic diversity of these isolates. Five out of 102 samples were positive for L. monocytogenes. Three different serotypes were detected, and all of the isolates were potentially pathogenic. Low genetic diversity was determined among isolated L. monocytogenes.

Mannheimia haemolytica and Bibersteinia trehalosi serotypes isolated from lambs with ovine respiratory complex in Spain

Ovine respiratory complex causes significant economic losses in ovine production systems around the world. Mannhemia haemolytica and Bibersteinia trehalosi are the two most frequently isolated bacterial species. In this study, bacterial isolates of M. haemolytica and B. trehalosi isolated from dead lambs were serotyped by means of indirect haemagglutination, with the general aim to improve information in the preparation for candidate strains for relevant vaccines. In total, 84 isolates were serotyped. Eight different M. haemolytica serotypes and four different B. trehalosi serotypes were identified. The most frequentM. haemolytica serotypes were A2 (29% of isolates), A12 (18%) and A1 (12%), while B. trehalosi were predominantly T4 (40% of isolates) and a group sharing characteristics of T3 and T15 serotypes (43%). Isolation of T4 serotype was associated with lack of consolidated lesions in lungs, whilst isolation of T3-T15 group was associated with lung consolidation. It is concluded that a potential vaccine to control the disease presented as a bacterin based on outer membrane proteins and leucotoxins of the organisms, it should contain the above, frequently implicated serotypes. Alternatively, vaccines based on iron-regulated proteins can be possible replacements.

Serotyping and antibiotic susceptibility patterns of Vibrio and Shigella isolates from diarrheal patients visiting a Tropical and Infectious Diseases Hospital in central Nepal

BackgroundDiarrheal diseases are the major infectious disease in developing countries like Nepal. Lack of proper sanitation and antimicrobial resistance gained by microbes have challenged to address diarrheal diseases in resource-limited countries. Early diagnosis of disease and proper antibiotic treatment can significantly reduce the disease burden. This study was designed to determine the recent antimicrobial susceptibility pattern of Vibrio cholerae and Shigella spp. to assure the proper antibiotic treatment. Stool specimens were processed following microbiological protocol and identified by biochemical and serological tests recommended by the Clinical Laboratory Standard Institute.ResultsOut of total 640 analyzed stool samples, 50 were culture positive, among them 29 were Shigella spp. (64.4%) and 21 were V. cholerae (46.6%). All V. cholerae strains belonged to the serogroup O1 and serovar Ogawa. Among the Shigella spp., Shigella flexneri 17 (59%) topped the list of serotype followed by Shigella sonnei 8 (28%), Shigella dysenteriae 3 (10%) and Shigella boydii 1 (3%) respectively. All the V. cholerae isolates (100%) were sensitive to cefotaxime while 71% were sensitive to tetracycline but 100 and 90.4% were resistance to co-trimoxazole and nalidixic acid respectively. Shigella isolates were mostly susceptible to cefotaxime (97%) while ciprofloxacin (48%) and ofloxacin (55%) were less effective drugs.ConclusionsThese results on the prevalence of enteropathogens and their antibiotic resistance pattern may help to guide accurate choice of therapy in clinical setting. Hence, development of evidence based National Guidelines for the treatment of diarrhea is needed.

Bayesian hierarchical model of ceftriaxone resistance proportions among Salmonella serotype Heidelberg infections

The National Antimicrobial Resistance Monitoring System (NARMS) at the Centers for Disease Control and Prevention tracks resistance among Salmonella infections. The annual number of Salmonella isolates of a particular serotype from states may be small, making direct estimation of resistance proportions unreliable. We developed a Bayesian hierarchical model to improve estimation by borrowing strength from relevant sampling units. We illustrate the models with different specifications of spatio-temporal interaction using 2004–2013 NARMS data for ceftriaxone-resistant Salmonella serotype Heidelberg. Our results show that Bayesian estimates of resistance proportions were smoother than observed values, and the difference between predicted and observed proportions was inversely related to the number of submitted isolates. The model with interaction allowed for tracking of annual changes in resistance proportions at the state level. We demonstrated that Bayesian hierarchical models provide a useful tool to examine spatio-temporal patterns of small sample size such as those found in NARMS.

Serotype distribution and clinical correlation of Streptococcus agalactiae causing invasive disease in infants and children in Taiwan.

Streptococcus agalactiae, or group B Streptococcus (GBS), remains to be one of the leading pathogens causing invasive infections in infants. The clinical GBS isolates from sterile sites of patients younger than 18 years old were collected from October 1998 to December 2014 in two hospitals in Taiwan. Medical records were retrospectively reviewed. Every isolate was serotyped with a multiplex PCR assay. Multilocus sequence typing (MLST) was performed in representative isolates of different serotypes. A total of 205 GBS isolates were collected from 181 patients with 182 infection episodes. Serotype Ia was the most common in patients less than 72h old, whereas III the most common in patients older than 72h. In early-onset disease (0-6 days), Ia and III each caused 27.5% of the infection, followed by Ib (14.5%). In late-onset disease (7-89 days), serotype III predominated (75.3%), followed by Ia (10.1%) and Ib (6.8%). Thirty-one episodes (17%) were complicated with culture-confirmed meningitis. We compared serotype Ia and III patients, and found that serotype Ia patients were significantly younger (median age, 3 days), had more perinatal maternal fever and higher mortality. ST17 and ST19 were exclusively found in serotype III, while ST23 and ST24 comprised of 85% of serotype Ia. In Taiwan, serotypes Ia and III are the most common cause for early-onset and late-onset neonatal GBS infections, respectively. Some differences in the clinical features of invasive GBS infections caused by serotype Ia and III were observed.

Serotype, virulence profile, antimicrobial resistance and macrolide-resistance determinants in Streptococcus agalactiae isolates in pregnant women and neonates in Catalonia, Spain

IntroductionStreptococcus agalactiae, or group B streptococci (GBS), is the main aetiological agent of early neonatal sepsis in developed countries. This microorganism belongs to the gastrointestinal tract microbiota wherefrom it can colonize the vagina and be vertically transmitted to the child either before or at birth, and subsequently cause infection in the newborn. Approximately, 50% of newborns born to women with GBS become colonized, with 1–2% developing early neonatal infection if no preventive intervention is performed. The aim of this study was to characterize and compare serotypes, virulence factors and antimicrobial resistance of GBS isolates collected from pregnant women and newborns in several hospitals in Catalonia. Methods242 GBS strains were analyzed including 95 colonizers and 68 pathogenic strains isolated from pregnant women, and 79 strains isolated from neonates with sepsis in order to determine serotype, virulence and antimicrobial resistance. ResultsSerotype distribution was different among the three groups, with serotypes Ia and II being significantly more frequent among colonizing strains (p=0.001 and 0.012, respectively). Virulence factors bca and scpB were significantly more frequent among neonatal strains than pathogenic or colonizing strains (p=0.0001 and 0.002, respectively). Pathogenic strains were significantly more resistant to erythromycin, clindamycin and azithromycin than their non-pathogenic counterparts. ConclusionsTaking into account that neonatal sepsis represents a significant problem on a global scale, epidemiological surveillance, antimicrobial resistance and GBS virulence at the local level could provide important knowledge about these microorganisms as well as help to improve treatment and prevent invasive infection caused by this microorganism.

Exploring target-specific primer extension in combination with a bead-based suspension array for multiplexed detection and typing using Streptococcus suis as a model pathogen.

We investigated the feasibility of an assay based on target-specific primer extension, combined with a suspension array, for the multiplexed detection and typing of a veterinary pathogen in animal samples, using Streptococcus suis as a model pathogen. A procedure was established for simultaneous detection of 6 S. suis targets in pig tonsil samples (i.e., 4 genes associated with serotype 1, 2, 7, or 9, the generic S. suis glutamate dehydrogenase gene [gdh], and the gene encoding the extracellular protein factor [epf]). The procedure was set up as a combination of protocols: DNA isolation from porcine tonsils, a multiplex PCR, a multiplex target-specific primer extension, and finally a suspension array as the readout. The resulting assay was compared with a panel of conventional PCR assays. The proposed multiplex assay can correctly identify the serotype of isolates and is capable of simultaneous detection of multiple targets in porcine tonsillar samples. The assay is not as sensitive as the current conventional PCR assays, but with the correct sampling strategy, the assay can be useful for screening pig herds to establish which S. suis serotypes are circulating in a pig population.

Assessment of Listeria monocytogenes virulence in the Galleria mellonella insect larvae model.

Several animal models have been used to understand the molecular basis of the pathogenicity, infectious dose and strain to strain variation of Listeria monocytogenes. The greater wax worm Galleria mellonella, as an alternative model, provides some useful advantages not available with other models and has already been described as suitable for the virulence assessment of various pathogens including L. monocytogenes. The objectives of this study are: 1) confirming the usefulness of this model with a wide panel of Listeria spp. including non-pathogenic L. innocua, L. seeligeri, L. welshimeri and animal pathogen L. ivanovii; 2) assessment of virulence of several isogenic in-frame deletion mutants in virulence and stress related genes of L. monocytogenes and 3) virulence assessment of paired food and clinical isolates of L. monocytogenes from 14 major listeriosis outbreaks occurred worldwide between 1980 and 2015. Larvae injected with different concentrations of Listeria were incubated at 37°C and monitored over seven days for time needed to kill 50% of larvae (LT50) and to determine change of bacterial population in G. mellonella, 2 and 24 hours post-inoculation. Non-pathogenic members of Listeria and L. ivanovii showed significantly (P < 0.05) higher LT50 (lower virulence) than the wild type L. monocytogenes strains. Isogenic mutants of L. monocytogenes with the deletions in prfA, plcA, hly, actA and virR genes, also showed significantly (P < 0.05) higher LT50 than the wild type strain at the inoculum of 106CFU/larva. Food isolates had significantly (P < 0.05) lower virulence than the paired clinical isolates, at all three inoculum concentrations. L. monocytogenes strains related to non-invasive (gastroenteritis) outbreaks of listeriosis showed significantly (P < 0.05) lower virulence than isolates of the same serotype obtained from outbreaks with invasive symptoms. The difference, however, was dose and strain- dependent. No significant differences in virulence were observed among the serotype tested in this study.

Genetic diversity of the O antigens of Proteus species and the development of a suspension array for molecular serotyping.

Proteus species are well-known opportunistic pathogens frequently associated with skin wound and urinary tract infections in humans and animals. O antigen diversity is important for bacteria to adapt to different hosts and environments, and has been used to identify serotypes of Proteus isolates. At present, 80 Proteus O-serotypes have been reported. Although the O antigen structures of most Proteus serotypes have been identified, the genetic features of these O antigens have not been well characterized. The O antigen gene clusters of Proteus species are located between the cpxA and secB genes. In this study, we identified 55 O antigen gene clusters of different Proteus serotypes. All clusters contain both the wzx and wzy genes and exhibit a high degree of heterogeneity. Potential functions of O antigen-related genes were proposed based on their similarity to genes in available databases. The O antigen gene clusters and structures were compared, and a number of glycosyltransferases were assigned to glycosidic linkages. In addition, an O serotype-specific suspension array was developed for detecting 31 Proteus serotypes frequently isolated from clinical specimens. To our knowledge, this is the first comprehensive report to describe the genetic features of Proteus O antigens and to develop a molecular technique to identify different Proteus serotypes.

16S ribosomal RNA sequencing and molecular serotyping of Avibacterium paragallinarum isolated from Indian field conditions.

Aim:This study was aimed at identifying Indian field isolates of Avibacterium paragallinarum on both molecular as well as serological levels that cause infectious coryza in chickens.Materials and Methods:Species-specific polymerase chain reaction (HPG-2 PCR), and 16S ribosomal RNA (rRNA) sequencing were employed for molecular identification. Whereas, multiplex PCR technique was used for serological identification of Indian field isolates of A. paragallinarum.Results:All three field isolates were identified as A. paragallinarum using HPG-2 PCR. The species-specific PCR results were validated using 16S rRNA sequencing. The partial 16S rRNA sequences obtained from all three isolates showed 96-99% homology with the NCBI database reference strains of A. paragallinarum. The aligned partial sequences of 16S rRNA were submitted to GenBank, and accession numbers were obtained. Multiplex PCR-based molecular serotyping showed that there are three serotypes of field isolates of A. paragallinarum, namely, strain IND101 is serovar A, strain IND102 is serovar B, and strain IND103 is serovar C.Conclusion:HPG-2 PCR, 16S rRNA sequencing, and multiplex PCR are proved to be more accurate, sensitive, and reliable diagnostic tools for molecular and serological identification of A. paragallinarum field isolates. These diagnostic methods can substitute conventional cultural characterization and would be much valuable to formulate quick and correct prevention and control measures against this detrimental poultry pathogen.

Characterization of Streptococcus pneumoniae invasive serotype 19A isolates from Argentina (1993-2014).

The aim of this study was to characterize Streptococcus pneumoniae serotype 19A isolates causing invasive pneumococcal disease in children, collected in Argentina between 1993 and 2014. A total of 176 isolates serotype 19A were analyzed. There was an increase in the proportion of serotype 19A isolates from 3% in 1993 to 6% in 2011, prior to the introduction of PCV13 in 2012, and from 2012 to 2014 its proportion gradually decreased. Penicillin resistance among serotype 19A isolates throughout the study period was 65.9%, but a significant increase was observed from 0% in 1993 to 87.5% in 2014. Genetic relationship of the isolates was determined by PFGE and selected strains were studied by MLST. Most of the isolates belonged to two clonal types: A (54.5%) and B (11.4%). Isolates of clonal type A were ST1131, a single locus variant of ST172 and accounted for 54% of the total collection. They were detected for the first time in our country in 1997 and most of them (93%) were penicillin non susceptible. Isolates of clonal type B were ST8121, a single locus variant of ST199, and were mainly susceptible to penicillin. These two clonal types are still in circulation and appear to be responsible for the dissemination of S. pneumoniae serotype 19A invasive isolates in our country.

A novel genetic variant of Streptococcus pneumoniae serotype 11A discovered in Fiji

ObjectivesAs part of annual cross-sectional Streptococcus pneumoniae carriage surveys in Fiji (2012–2015), we detected pneumococci in over 100 nasopharyngeal swabs that serotyped as ‘11F-like’ by microarray. We examined the genetic basis of this divergence in the 11F-like capsular polysaccharide (cps) locus compared to the reference 11F cps sequence. The impact of this diversity on capsule phenotype, and serotype results using genetic and serologic methods were determined. MethodsGenomic DNA from representative 11F-like S. pneumoniae isolates obtained from the nasopharynx of Fijian children was extracted and subject to whole genome sequencing. Genetic and phylogenetic analyses were used to identify genetic changes in the cps locus. Capsular phenotypes were evaluated using the Quellung reaction and latex agglutination. ResultsCompared to published 11F sequences, the wcwC and wcrL genes of the 11F-like cps locus are phylogenetically divergent, and the gct gene contains a single nucleotide insertion within a homopolymeric region. These changes within the DNA sequence of the 11F-like cps locus have modified the antigenic properties of the capsule, such that 11F-like isolates serotype as 11A by Quellung reaction and latex agglutination. ConclusionsThis study demonstrates the ability of molecular serotyping by microarray to identify genetic variants of S. pneumoniae and highlights the potential for discrepant results between phenotypic and genotypic serotyping methods. We propose that 11F-like isolates are not a new serotype but rather are a novel genetic variant of serotype 11A. These findings have implications for invasive pneumococcal disease surveillance as well as studies investigating vaccine impact.

Detection of Serotype Gene of Klebsiella Pneumoniae Isolated from Different Clinical Cases of Hospitalized Infections in Al-Diwaniya city

This study aimed to identify serotype of Klebsiella Pneumonia isolated from different clinical cases of hospitalized infections( urinary tract infection, respiratory infection, burns &amp; wounds) by using polymerase chain reaction(PCR).A total of 110 clinical specimens from in-patients with nosocomial infections(including 47 respiratory infection,37 UTI , burns &amp; wound infections 26) in Al-Diwaniya Teaching Hospital during the period from December 2012 –March 2013 were collected. K. Pneumonia isolated from 35.4% of the specimens distributed as 18.18% sputum specimens,10.90% urine specimens &amp; 6.36% burns &amp; wounds specimens.&#x0D; K1,K2,K5,K20,K54 &amp; K57 serotypes of K. Pneumonia were successfully detected in multiplex PCR.The results revealed that 28 specimens(25.4%) were type able including 7 positive K1(Amplicon size 1046bp) serotype isolates ( 4 from sputum,2 from urine &amp; 1 from burn), 6 positive of K2(Amplicon size1121) serotype isolates (3 from urine,2 from sputum &amp; 1 from wound),3 positive for K5(Amplicon size 999bp) serotype isolates( 2 from sputum &amp; 1 from urine),2 positive for K20(Amplicon size 1116bp) serotype isolates from urine 2 positive of K54(Amplicon size 881bp) serotype isolates were one from sputum &amp; the other from urine&amp; finally 8 positive of K57(Amplicon size 1182bp) serotype isolates(4 from sputum,2 from urine &amp; 2 from burns &amp; wounds).&#x0D; However, among 11 (10%) specimens, K. Pneumonia were non type able.&#x0D; This study revealed that there were predominance of K1,K2 &amp; K57 serotype isolates in sputum, urine burns &amp; wounds of patients with nosocomial infections.

Molecular detection of Stx1 and Stx2 genes in E.Coli O157:H7 isolated from Cow's and Buffalo's soft cheese samples inBabylon Province, using Multiplex PCR technique.

Colonies of E.Coli O157:H7 were isolated from 80 locally produced Cow's and Buffalo's soft cheese samples that were collected randomly at weekly intervals (5 samples/ week) from various retail markets in different locations of babylon province during two climatic periods(40 samples /species/season) where the first periad was extended from the begining of December 2015 to the end of February 2016 while the second period was extended from the begining of July to the end of September 2016.The identification of E.Coli O157:H7 isolates were confirmed based on their cultural, biochemical and seralogical characteristics using the commercial latex agglutination test kit and by duplex PCR technique. Data revealed that there was a significant (P≤ 0.05) seasonal variation in the prevalence of E.Coli O157:H7 where all Cow's and Buffalo's soft cheese samples had significantly (P≤ 0.05) higher prevalence of E.Coli O157:H7 in summer season (50% and 40% respectively) than in winter season (25% and 15% respectively).It was found that all of the 80 bovine soft cheese samples had significantly (p&lt;0.05) higher prevalence of E.Coli O157:H7 in summer (45%) than in winter (20%) seasons.The results of the diagnosis of E.coli O157:H7 were confirmed by PCR assay which showed that,six culturing isolates serotype E.coli O157:H7 were postive by PCR assay and five of these isolates expressed gene of Stx1 whearse one isolate expressed gene of Stx2 .

Aggregatibacter actinomycetemcomitans serotype prevalence and antibiotic resistance in a UK population with periodontitis.

Aggregatibacter actinomycetemcomitans is a recognised pathogen involved in aggressive periodontitis. Seven serotypes of A. actinomycetemcomitans exist with a range of virulence and distribution dependent on ethnicity and geography. The ability of A. actinomycetemcomitans to invade soft tissue can necessitate the use of systemic antibiotics for treatment, however variations in its antibiotic susceptibility exist dependent on geographical location. Serotypes of A. actinomycetemcomitans isolates from a UK cohort of 50 patients with aggressive periodontitis were determined by PCR. Resistance of the isolates to eight antibiotics [penicillin (1U), amoxicillin (2μg), amoxicillin/clavulanic acid (30μg), metronidazole (5μg), clindamycin (2μg), tetracycline (10μg), ciprofloxacin (5μg) and ceftazidime (30μg)] were determined by disk diffusion according to BSAC guidelines. Prevalences of serotypes a, c, b, e and mixed serotypes were 48%, 22%, 2%, 2% and 12%, respectively. The serotype of isolates from seven patients (14%) could not be deduced by PCR. Of the 56 isolates tested, 100% were resistant to penicillin and metronidazole, 87.5% to clindamycin, 83.9% to amoxicillin and 76.8% to ceftazidime. Low rates of resistance to tetracycline (8.9% resistant) and amoxicillin/clavulanic acid (14.3% resistant) were observed, whereas no isolates were resistant to ciprofloxacin. As in a number of publications the suggested treatment of aggressive periodontitis includes the combined use of amoxicillin with metronidazole, these results highlight the need for culture and antimicrobial susceptibility investigations in patients with aggressive periodontitis prior to systemic use of antibiotics concomitantly to periodontal therapy.

Characteristics of pediatric invasive pneumococcal diseases and the pneumococcal isolates in Suzhou, China before introduction of PCV13

BackgroundData on characteristics of invasive pneumococcal diseases (IPD) is limited in China. We aimed to understand the clinical features and explore the molecular characteristics of the pneumococcal isolates in China. MethodsSince 2010, we prospectively collected the pneumococcal isolates and the IPD patients’ demographic and clinical information in Suzhou University Affiliated Children’s Hospital (SCH). The antibiotic susceptibility, serotypes, genotypes of Streptococcus pneumoniae strains were identified by E-test, quellung reaction and/or multiplex PCR, and multi-locus sequence typing, respectively. ResultsDuring the period from January 2010 to December 2015, a total of 80 IPD patients were identified. They were diagnosed as meningitis (31.3%), septicemia (27.5%), pneumonia (21.3%) and others (20.0%). About half of them required vancomycin treatment, 42.5% were admitted to ICUs, 36.2% had complications and 6.2% were hospitalized for over 1year. The most common serotypes of the pneumococcal isolates were serotypes 6B and 14, the coverage of PCV13 was 92.5%, and CC236s and CC199s were the most common clone complexes. ConclusionsPediatric IPD patients had severe clinical symptoms, demanded intensive treatment, suffered poor prognosis and substantial burden. The pneumococcal isolates’ serotype coverage of PCV13 vaccine was high, which leads to implication of PCV vaccine usage among children in China.

Streptococcus pneumoniae antimicrobial resistance decreased in the Helsinki Metropolitan Area after routine 10-valent pneumococcal conjugate vaccination of infants in Finland.

Since the introduction of 10-valent pneumococcal conjugate vaccine (PCV10) into the Finnish national vaccination program in September 2010, the incidence of invasive pneumococcal disease in children has decreased steeply in Finland. We studied the antimicrobial susceptibility of invasive and non-invasive Streptococcus pneumoniae (pneumococcus) isolated in the Helsinki Metropolitan Area during 2009-2014. We divided the data into two age groups: isolates from patients <5years old and ≥5years old. We also studied the serotype distribution of invasive isolates and of a subset of non-invasive multidrug-resistant isolates. The invasive isolate numbers recovered from patients aged <5years old declined from 33/228 (15%) in 2009 to 8/208 (4%) in 2014 (p<0.001) and non-invasive isolate numbers declined during the same time period from 221/595 (37%) to 119/432 (28%) (p<0.001). At the same time, the proportion of penicillin non-susceptible non-invasive isolates in this age group decreased from 25% (56/220) to 13% (15/119) (p=0.001) and multidrug-resistant isolates from 22% (49/220) to 6% (7/119) (p<0.001), respectively. The number of PCV10 serotype isolates also decreased among the serotyped multidrug-resistant non-invasive isolates. Among patients aged ≥5years old, the isolate numbers did not show a similar decreasing trend compared to the younger group and, further, the number of non-PCV10 serotype isolates increased in invasive cases. To conclude, the antimicrobial non-susceptibility of pneumococcus has decreased markedly, especially among young patients (<5years old), following PCV10 implementation in Finland.