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1.
Croat Med J ; 63(2): 156-165, 2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35505649

RESUMO

AIM: To assess serotype distribution, antibiotic resistance, and vaccine coverage against Streptococcus pneumoniae causing invasive infections in Croatian adults from 2005 to 2019. METHODS: In this retrospective study, invasive pneumococcal strains were collected through a microbiological laboratory network with country coverage >95%. Capsular typing was performed with the Quellung reaction. In vitro susceptibility testing was carried out according to the European Committee on Antimicrobial Susceptibility Twating guidelines. In macrolide-resistant isolates, the presence of ermB and mefA genes was evaluated. RESULTS: During the fifteen-year study period, 1123 invasive pneumococcal isolates were obtained. The most prevalent serotypes were 3, 14, 19A, 9V, 7F, and 23F, comprising 60% of all invasive pneumococcal isolates. Serotype 3 was the dominant serotype, with the highest prevalence in patients ≥65 years of age. Penicillin susceptibility, increased exposure was 18.6%, mostly associated with serotypes 14 and 19A. Resistance to penicillin was low (<1%). Macrolide resistance was 23%, mostly associated with serotypes 14, 19A, and 19F. The coverage with 13-valent conjugate vaccine (PCV13) and 23-valent polysaccharide vaccine (PPV23) was 80.2% and 93.6%, respectively. CONCLUSIONS: The incidence of invasive pneumococcal disease in adults is highest in patients ≥65 years of age. Penicillin susceptibility, increased exposure and macrolide resistance were mostly associated with serotypes 14 and 19A. PCV13 and PPV23 provide very high serotype coverage. Future studies should evaluate the effects of the 10-valent vaccine, introduced in the Croatian National Immunization Program in June 2019, on serotype distribution and antibiotic resistance rates.


Assuntos
Antibacterianos , Streptococcus pneumoniae , Adulto , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Croácia/epidemiologia , Farmacorresistência Bacteriana/genética , Humanos , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Penicilinas/farmacologia , Estudos Retrospectivos , Sorogrupo , Sorotipagem , Streptococcus pneumoniae/genética
3.
Front Cell Infect Microbiol ; 12: 824449, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35392607

RESUMO

Background/Objective: The frequencies of non-susceptibility against common antibiotics among pneumococci vary greatly across the globe. When compared to other European countries antibiotic resistance against penicillin and macrolides has been uncommon in Sweden in recent years. Multidrug resistance (MDR) is, however, of high importance since relevant treatment options are scarce. The purpose of this study was to characterize the molecular epidemiology, presence of resistance genes and selected virulence genes of extensively drug-resistant (XDR) (n=15) and MDR (n=10) Streptococcus pneumoniae detected in clinical respiratory tract samples isolated from patients in a southern Swedish county 2016-2018. With the aim of relating them to global MDR pneumococci. Methods: Whole genome sequencing (WGS) was performed to determine molecular epidemiology, resistance genes and presence of selected virulence factors. Antimicrobial susceptibility profiles were determined using broth microdilution testing. Further analyses were performed on isolates from the study and from the European nucleotide archive belonging to global pneumococcal sequence cluster (GPSC) 1 (n=86), GPSC9 (n=55) and GPSC10 (n=57). Bacteria were analyzed regarding selected virulence determinants (pilus islet 1, pilus islet 2 and Zinc metalloproteinase C) and resistance genes. Results: Nineteen of 25 isolates were related to dominant global MDR lineages. Seventeen belonged to GPSC1, GPSC9 or GPSC10 with MDR non-PCV serotypes in GPSC9 (serotype 15A and 15C) as well as GPSC10 (serotype 7B, 15B and serogroup 24). Pilus islet-1 and pilus islet-2 were present in most sequence types belonging to GPSC1 and in two isolates within GPSC9 but were not detected in isolates belonging to GPSC10. Zinc metalloproteinase C was well conserved within all analyzed isolates belonging to GPSC9 but were not found in isolates from GPSC1 or GPSC10. Conclusions: Although MDR S. pneumoniae is relatively uncommon in Sweden compared to other countries, virulent non-PCV serotypes that are MDR may become an increasing problem, particularly from clusters GPSC9 and GPSC10. Since the incidence of certain serotypes (3, 15A, and 19A) found among our MDR Swedish study isolates are persistent or increasing in invasive pneumococcal disease further surveillance is warranted.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas , Sistema Respiratório , Sorogrupo , Sorotipagem , Suécia/epidemiologia , Fatores de Virulência/genética , Zinco
4.
BMC Infect Dis ; 22(1): 338, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-35382757

RESUMO

BACKGROUND: To analyse clinical characteristics, antibiotic susceptibility, and risk factors for mortality in paediatric invasive pneumococcal disease (IPD) in Beijing. METHODS: Paediatric IPD patients in our hospital were retrospectively collected from 2012 to 2017. Clinical manifestations, laboratory tests, antimicrobial susceptibility and serotype of isolates, and risk factors for mortality of IPD were analysed. RESULTS: Overall, 186 IPD cases were enrolled. The major manifestations were meningitis (76), pneumonia with bacteraemia (60), bacteraemia without focus (21), and pneumonia with empyaema (22). Of 72 cases with underlying diseases, leukaemia (18.0%), congenital heart disease (15.3%), primary immunodeficiency disease (12.5%), nephrotic syndrome (12.5%), and cerebrospinal fluid leakage (12.5%) were most common. In total 96.9% of isolates would have been covered by the pneumococcal conjugate vaccine (PCV13), including 19F (32.8%), 19A (23.4%), 4 (17.2%), and 23F (9.4%). Nonsusceptibility rates of penicillin, cefotaxime, and cefepime among nonmeningitis patients increased between 2012 and 2017; The mortality rate was 21.5%. Meningitis, respiratory failure, multiple organ failure, and white blood cell count < 4000 cells/µL were independent risk factors for mortality. CONCLUSION: Meningitis was the most common clinical manifestation of IPD, and was frequently associated with death. Strains in the PCV13 vaccine would cover most of the cases, and so wider use of PCV13 should be considered.


Assuntos
Antibacterianos , Infecções Pneumocócicas , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Pequim/epidemiologia , Criança , Farmacorresistência Bacteriana , Humanos , Lactente , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas , Estudos Retrospectivos , Fatores de Risco , Sorogrupo , Sorotipagem , Streptococcus pneumoniae
5.
Microbiologyopen ; 11(2): e1272, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35478285

RESUMO

Actinobacillus pleuropneumoniae is the etiological agent of porcine pleuropneumonia, a respiratory infectious disease responsible for global economic losses in the pig industry. From a monitoring perspective as well as due to the different courses of disease associated with the various serovars, it is essential to distinguish them in different herds or countries. In this study, we developed a novel high resolution melting (HRM) assay based on reference strains for each of the 19 known serovars and additional 15 clinical A. pleuropneumoniae isolates. The novel HRM comprises the species-specific APP-HRM1 and two serovar-specific HRM assays (APP-HRM2 and APP-HRM3). APP-HRM1 allowed polymerase chain reaction (PCR) amplification of apxIV resulting in an A. pleuropneumoniae specific melting curve, while nadV specific primers differentiated biovar 2 from biovar 1 isolates. Using APP-HRM2 and APP-HRM3, 13 A. pleuropneumoniae serovars can be determined by inspecting the assigned melting temperature. In contrast, serovar 3 and 14, serovar 9 and 11, and serovar 5 and 15 have partly overlapping melting temperatures and thus represent a challenge to accurately distinguish them. Consequently, to unambiguously ensure the correct assignment of the serovar, it is recommended to perform the serotyping HRM assay using a positive control for each serovar. This rapid and user-friendly assay showed high sensitivity with 1.25 fg-125 pg of input DNA and a specificity of 100% to identify A. pleuropneumoniae. Characteristic melting patterns of amplicons might allow detecting new serovars. The novel HRM assay has the potential to be implemented in diagnostic laboratories for better surveillance of this pathogen.


Assuntos
Infecções por Actinobacillus , Actinobacillus pleuropneumoniae , Doenças dos Suínos , Infecções por Actinobacillus/diagnóstico , Infecções por Actinobacillus/veterinária , Actinobacillus pleuropneumoniae/genética , Animais , Sorogrupo , Sorotipagem , Suínos , Doenças dos Suínos/diagnóstico
6.
Int J Food Microbiol ; 370: 109665, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35395487

RESUMO

Vibrio fluvialis is an emerging foodborne pathogen that causes severe infections. Serotyping based on surface polysaccharide antigens is important for the clinical detection and epidemiological surveillance of pathogens such as V. fluvialis. For example, variation of the O-antigen, which is highly polymorphic and is responsible for the majority of antigenic variability on the bacterial cell surface, provides the basis for serotyping of Gram-negative bacteria. Currently, there has been no analysis of the O-antigen gene clusters in V. fluvialis. In this study, the putative O-antigen gene clusters of 18 V. fluvialis serogroups (O1-O18), which exhibit a high level diversity, were analyzed by whole-genome sequencing. A microsphere-based suspension array (MSA) based on O-serogroup-specific genes was developed for identification of V. fluvialis strains O1-O18 and evaluated for specificity and sensitivity in double-blind tests. Furthermore, analysis of 62 publicly available V. fluvialis genomes identified 13 new O-antigen gene cluster types. The detection sensitivity was determined to be 10-2 ng for genomic DNA and 103 CFU for pure cultures. When testing simulated samples in an oyster background, 2 to 20 CFU per gram inoculated could be detected after enrichment using this method. Our work provides an efficient tool for rapid detection and identification of V. fluvialis serogroups from clinical and environmental samples, with the potential for use in epidemiological investigations and food safety applications.


Assuntos
Antígenos O , Vibrio , Família Multigênica , Antígenos O/genética , Sorotipagem/métodos , Vibrio/genética
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(4): 443-447, 2022 Apr 06.
Artigo em Chinês | MEDLINE | ID: mdl-35488540

RESUMO

Objective: To study the epidemiological and pathogenic characteristics of Vibrio parahaemolyticus isolated from outbreaks cases in Guangdong Province, 2017-2020. Methods: Epidemiological characteristics of 87 outbreak events caused by Vibrio parahaemolyticus were analyzed. Strains were serotyped, and then analyzed by pulsed-field gel electrophoresis (PFGE). Results: The food-borne disease outbreak caused by Vibrio parahaemolyticus was found in 16 cities. 44.8% (39/87) and 37.9% (33/87) of the outbreaks occurred in hotels, restaurants and school canteens, respectively. Improper food processing and storage (40.2%, 35/87) and cross contamination caused by indiscriminate raw and cooked food (25.3%, 22/87) were the main causes of food-borne disease outbreaks of Vibrio parahaemolyticus. The main serotypes of patient derived strains were O3:K6 (87.5%) and O4:KUT (22.5%). The similarity value between O3:K6 type isolates was 65.5%-100.0%, and the PFGE pattern similarity value of O4:KUT type isolates was 66.5%-100.0%. Conclusion: Outbreaks caused by Vibrio parahaemolyticus are widely distributed in Guangdong province. It is necessary to strengthen the publicity and education on the correct handling of food in hotels, restaurants, schools, and unit canteens. O3:K6 and O4:KUT serotypes are the main serotypes of the outbreak. There is genetic diversity among the epidemic strains.


Assuntos
Doenças Transmitidas por Alimentos , Vibrioses , Vibrio parahaemolyticus , China/epidemiologia , Surtos de Doenças , Doenças Transmitidas por Alimentos/epidemiologia , Humanos , Sorotipagem , Vibrioses/epidemiologia , Vibrio parahaemolyticus/genética
8.
Front Cell Infect Microbiol ; 12: 863435, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35433512

RESUMO

There is a growing demand for rapid, sensitive, field-deployable nucleic acid tests for cholera, which usually occurs in rural areas. In this study, we developed a Cas12a-assisted rapid isothermal detection (CARID) system for the detection of toxigenic V. cholerae serogroups O1 and O139 by combining recombinase-aided amplification and CRISPR-Cas (clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins). The results can be determined by fluorescence signal and visualized by lateral flow dipstick. We identified 154 V. cholerae strains and 129 strains of other intestinal diarrheagenic bacteria with a 100% coincidence rate. The limit of detection of CARID was 20 copies/reaction of V. cholerae genomic DNA, which is comparable to that of polymerase chain reaction (PCR) and qPCR. Multiple-CARID was also established for efficiency and economic considerations with an acceptable decrease in sensitivity. Simulated sample tests showed that CARID is suitable for complex samples. In conclusion, CARID is a rapid, sensitive, economically efficient, and portable method for the detection of V. cholerae, which makes it suitable for field responses to cholera.


Assuntos
Cólera , Vibrio cholerae O1 , Cólera/diagnóstico , Cólera/microbiologia , Toxina da Cólera , Humanos , Sorogrupo , Sorotipagem , Vibrio cholerae O1/genética
9.
Vaccine ; 40(15): 2258-2265, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35282927

RESUMO

BACKGROUND: Invasive pneumococcal disease (IPD) is associated with substantial morbidity and mortality in children and elderly populations. Serotype distribution and antibiotic susceptibility of IPD isolates are changing with the implementation of pneumococcal vaccination and increasing antibiotic use worldwide. We aimed to determine serotype distribution, antibiogram, and molecular epidemiology of pneumococci in the late stage of PCV13 era. METHODS: Prospective multicenter IPD surveillance study was conducted for adults aged ≥ 19 years from July 2019 to June 2021. Clinical and epidemiologic data were collected. In addition, antibiotic susceptibility test, serotype identification and multi-locus sequence typing (MLST) was taken for pneumococcal isolates. RESULTS: A total of 160 IPD cases were collected with mean age of 65.1 years (male, 72.5%). Serotyping was taken for 116 available pneumococcal isolates. PCV13 and PPSV23 serotypes were 32.8% (n = 38) and 56.0% (n = 65), respectively. Serotype 3 (13.8%) and 19A (9.5%) were the most common causative agents of IPD, followed by serogroup 11 (6.9%), 23A (6.9%), 10A (4.3%), and 15B (4.3%). Notably, 32.5% of invasive pneumococcal isolates were non-susceptible to ceftriaxone. Serotypes 11A, 11E and 19A pneumococci showed high ceftriaxone non-susceptible rate (80%, 100% and 81.8% respectively), and they were related to sequence type (ST) 166 and ST320. In comparison, most serotype 3 isolates were ceftriaxone susceptible and related to ST180. CONCLUSIONS: PCV serotypes, especially 3 and 19A, are still prevalent in adult IPDs, suggesting that individual PCV13 immunization would be necessary for the elderly people and chronically ill patients. Ceftriaxone non-susceptible rate was remarkably high in invasive pneumococcal isolates.


Assuntos
Ceftriaxona , Infecções Pneumocócicas , Adulto , Idoso , Ceftriaxona/uso terapêutico , Criança , Humanos , Lactente , Masculino , Tipagem de Sequências Multilocus , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Estudos Prospectivos , Sorogrupo , Sorotipagem , Adulto Jovem
10.
Comp Immunol Microbiol Infect Dis ; 83: 101777, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35228160

RESUMO

INTRODUCTION AND PURPOSE: Yersinia enterocolitica belongs to the family of Enterobacteriaceae and is a psychrophilic pathogen that is associated with foodborne infections. It usually causes gastroenteritis, mesenteric lymphadenitis, and septicemia. This study aimed to molecular detection, biotyping, and serotyping of Yersinia enterocolitica isolated from chicken livers in Tabriz. MATERIALS AND METHODS: One hundred chicken liver samples were collected randomly from poultry slaughterhouses in Tabriz for three months. After enrichment process, the presence of Yersinia enterocolitica in studied samples was determined through culture-based methods, biochemical and molecular tests. Then the biotype and serotype of the isolates were determined. RESULTS: 31 samples (31%) were positive for Yersinia enterocolitica by both phenotypic and molecular assays. Among positive samples, 25 (80.64%) had non-pathogenic biotype 1 A with serotype O: 5 (23 samples) and O: 8 (2 samples). 6 (19.36%) had biotype 1B and all of them had O: 3 serotype. The serotype Yersinia enterocolitica O: 9 was not found. CONCLUSION: the present study highlighted the significance of chicken liver as potential source of Yersinia enterocolitica infection in Tabriz city.


Assuntos
Yersiniose , Yersinia enterocolitica , Animais , Galinhas , Fígado , Sorotipagem/veterinária , Yersiniose/epidemiologia , Yersiniose/veterinária , Yersinia enterocolitica/genética
11.
J Clin Microbiol ; 60(4): e0211121, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35306833

RESUMO

To monitor the burden and changes in Haemophilus influenzae (Hi) disease, direct real-time PCR (drt-PCR) assays have been developed for Hi detection in monoplex form and its six serotypes in triplex form, directly from cerebrospinal fluid (CSF) specimens. These assays target the phoB gene for the species detection (Hi-phoB) and serotype-specific genes in region II of the capsule biosynthesis locus (Hi-abf and Hi-cde), identified through comparative analysis of Hi and non-Hi whole-genome sequences. The lower limit of detection (LLD) is 293 CFU/mL for the Hi-phoB assay and ranged from 11 to 130 CFU/mL for the triplex serotyping assays. Using culture as a reference method, the sensitivity and specificity of Hi-phoB, Hi-abf, and Hi-cde were 100%. Triplex serotyping assays also showed 100% agreement for each serotype compared to their corresponding monoplex serotyping assay. These highly sensitive and specific drt-PCR assays do not require DNA extraction and thereby reduce the time, cost, and handling required to process CSF specimens. Furthermore, triplex drt-PCR assays combine the detection of three serotypes in a single reaction, further improving testing efficiency, which is critical for laboratories that process high volumes of Hi specimens for surveillance and diagnostic purposes.


Assuntos
Haemophilus influenzae , Reação em Cadeia da Polimerase Multiplex , DNA , Haemophilus influenzae/genética , Humanos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Sorotipagem/métodos
12.
Comp Immunol Microbiol Infect Dis ; 84: 101792, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35325686

RESUMO

Stray cat populations can represent a significant threat of the transmission of zoonotic diseases such as salmonellosis. The objective of this study was to assess Salmonella carriage by free-living cats in Gran Canaria island and the Salmonella serovars involved, in order to inform to those responsible for the colonies about the possible risk factors. One hundred rectal swabs of feral cats were taken. Salmonella strains were serotyped in accordance with Kauffman-White-Le-Minor technique. Of a total of 100 animals under study, 19% were found to be positive to Salmonella spp. This is the first report that described the zoonotic serovars S. Nima, S. Bredeney, S. Grancanaria and S. Kottbus in cats. The present study demonstrates that feral cats may represent a source of risk for the spread of different Salmonella zoonotic serovars. It has been reported that there is a certain correlation between Salmonella isolates from pets and wild animals. Further studies are needed from other animal species and environmental sources to make this correlation.


Assuntos
Doenças do Gato , Salmonelose Animal , Salmonella enterica , Animais , Animais Selvagens , Doenças do Gato/epidemiologia , Gatos , Saúde Pública , Salmonella , Salmonelose Animal/epidemiologia , Sorogrupo , Sorotipagem/veterinária
13.
BMC Infect Dis ; 22(1): 110, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35100997

RESUMO

BACKGROUND: Discovery of new Toxoplasma gondii serotyping epitopes is important due to reports showing the influence of genotype on the severity of toxoplasmosis. In Turkey, genotypes belonging to type II, type III and Africa 1 lineages were mainly detected. The present study focused on to find out epitopes with high discriminative capacity to serotype these genotypes using well characterized strains isolated from Turkey. METHODS: To meet this objective, GRA6 and GRA7 genes were sequenced from strains belonging to the type II, III and Africa 1 lineages, and B cell epitopes inside these sequences were predicted by Bcepred and additional docking analysis was performed with B cell receptor. Based on these analyses, 22 peptides harboring lineage specific epitopes were synthesized. Then, the serotyping potency of these peptides was tested using peptide ELISA and well categorized serum samples collected from stray cats infected with genotypes of the different lineages type II (n:9), III (n:1) and Africa 1 (n:1). As a result of peptide-ELISA, a serotyping schema was constructed with peptides that show high discriminative capacity and this assay was validated by sera collected from humans after an outbreak (n:30) and mother/newborn pair sera (n:3). Later, the validated serotyping schema was used to serotype a larger group of human (n:38) and cat (n:24) sera. RESULTS: Among 22 peptides, GRA6II/c, GRA7III/d, and GRA6 Africa 1/b epitopes have shown discriminative capacity. During the validation of peptide-ELISA, the serotype of toxoplasmosis outbreak and mother/newborn cases were detected to be serotype II. Moreover, the analyses in a larger group showed that serotype II was prevalent in humans and stray cats. CONCLUSIONS: Overall, the results showed that the serotyping schema could be successfully used to serotype T. gondii infections caused by type II, III and Africa 1 genotype.


Assuntos
Toxoplasma , Animais , Antígenos de Protozoários/genética , Gatos , Surtos de Doenças , Ensaio de Imunoadsorção Enzimática , Humanos , Peptídeos , Sorotipagem , Toxoplasma/genética
14.
Sci Rep ; 12(1): 3189, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35210526

RESUMO

Haemophilus influenzae is an opportunistic pathogen adapted to the human respiratory tract. Non-typeable H. influenzae are highly heterogeneous, but few studies have analysed the genomic variability of capsulated strains. This study aims to examine the genetic diversity of 37 serotype f isolates from the Netherlands, Portugal, and Spain, and to compare all capsulated genomes available on public databases. Serotype f isolates belonged to CC124 and shared few single nucleotide polymorphisms (SNPs) (n = 10,999), but a high core genome (> 80%). Three main clades were identified by the presence of 75, 60 and 41 exclusive genes for each clade, respectively. Multi-locus sequence type analysis of all capsulated genomes revealed a reduced number of clonal complexes associated with each serotype. Pangenome analysis showed a large pool of genes (n = 6360), many of which were accessory genome (n = 5323). Phylogenetic analysis revealed that serotypes a, b, and f had greater diversity. The total number of SNPs in serotype f was significantly lower than in serotypes a, b, and e (p < 0.0001), indicating low variability within the serotype f clonal complexes. Capsulated H. influenzae are genetically homogeneous, with few lineages in each serotype. Serotype f has high genetic stability regardless of time and country of isolation.


Assuntos
Cápsulas Bacterianas/genética , Genoma Bacteriano , Instabilidade Genômica , Haemophilus influenzae/genética , Genômica , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/classificação , Humanos , Tipagem de Sequências Multilocus , Países Baixos , Filogenia , Polimorfismo de Nucleotídeo Único , Portugal , Sorogrupo , Sorotipagem/métodos , Espanha
15.
Viruses ; 14(2)2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35215844

RESUMO

Fowl adenoviruses (FAdVs) are infectious agents, mainly of chickens, which cause economic losses to the poultry industry. Only a single serotype, namely FAdV-5, constitutes the species Fowl aviadenovirus B (FAdV-B); however, recently, phylogenetic analyses have identified divergent strains of the species, implicating a more complex scenario and possibly a novel serotype. Therefore, field isolates of the species were collected to investigate the contemporary diversification within FAdV-B, including traditional serotyping. Full genomes of fourteen FAdV-B strains were sequenced and four strains, possessing discriminatory mutations in the antigenic domains, were compared using virus cross-neutralization. Essentially, strains with identical antigenic signatures to that of the first described divergent strain were found in the complete new dataset. While chicken antiserum against FAdV-5 reference strain 340 could not neutralize any of the newly isolated viruses, low homologous/heterologous titer ratios were measured reciprocally. Although they argue against a new serotype, our results indicate the emergence of escape variants in FAdV-B. Charge-influencing amino acid substitutions accounted for only a few mutations between the strains; still, these enabled one-way cross-neutralization only. These findings underline the continued merit of the cross-neutralization test as the gold standard for serotyping, complementary to advancing sequence data, and provide a snapshot of the actual diversity and evolution of species FAdV-B.


Assuntos
Aviadenovirus/classificação , Aviadenovirus/genética , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Aviadenovirus/imunologia , Proteínas do Capsídeo/química , Galinhas/virologia , Genoma Viral , Modelos Moleculares , Tipagem Molecular , Mutação , Testes de Neutralização , Filogenia , Conformação Proteica , Sorogrupo , Sorotipagem , Sequenciamento Completo do Genoma
16.
Int J Food Microbiol ; 366: 109562, 2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35134634

RESUMO

Human listeriosis outbreaks are often associated with food products, which could be contaminated, at the same time, also by different clones of Listeria monocytogenes. This emphasize the need to type more than one L.monocytogenes isolate found in a single food or environmental sample. The purpose of the present study was to evaluate the presence of different L.monocytogenes strains in food and food production environment in order to understand if there is need to type more isolates from the same sample in case of presence of L.monocytogenes. Between 2011 and 2015, at the Italian National Reference Laboratory for L.monocytogenes, for each positive sample, from two to twenty-three isolates of L.monocytogenes were collected. All the isolates were characterized by conventional serotyping and pulsed field gel electrophoresis (PFGE). Moreover, isolates from the same sample, having indistinguishable PFGE profile, were subjected to whole genome sequencing in order to perform core genome Multi Locus Sequence Typing (cgMLST). Within each sample, more than one serotype and one pulsotype were found in 11.9% and 27.5%, respectively. For indistinguishable PFGE patterns the cgMLST analysis showed 96.2% of concordance demonstrating the added value of new sequencing technologies. This study has demonstrated the need to select and type more than one L.monocytogenes colony in one food or food environmental sample to detect the diversity of L.monocytogenes strains and facilitate downstream investigations and effective source attribution in foodborne outbreak inquiry.


Assuntos
Listeria monocytogenes , Listeriose , Eletroforese em Gel de Campo Pulsado , Microbiologia de Alimentos , Variação Genética , Humanos , Listeriose/epidemiologia , Tipagem de Sequências Multilocus , Estudos Retrospectivos , Sorotipagem
17.
J Antimicrob Chemother ; 77(5): 1444-1451, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35141750

RESUMO

OBJECTIVES: To compare the proportion of invasive and respiratory tract isolates of Streptococcus pneumoniae, including MDR and XDR strains, that demonstrated PCV-15 and PPSV-23 serotypes in Canada from 2007 to 2020. METHODS: The CANWARD study collected 2984 S. pneumoniae isolates from 2007 to 2020 (1054 invasive, 1930 respiratory). Serotyping was performed using the Quellung reaction. Antimicrobial susceptibility testing was performed using CLSI methods. MDR/XDR was defined as resistance to ≥3/≥5 antimicrobial classes, respectively. RESULTS: Overall, the proportion of vaccine serotypes demonstrating a PCV-15/PPSV-23 serotype was significantly higher in blood isolates (54.6%/76.2%, respectively) than respiratory isolates (38.9%/55.3%; P < 0.0001). Similarly, PCV-15 and PPSV-23 vaccine coverage was higher for blood isolates for all demographic categories, including both genders, all regions and all age groups (P ≤ 0.0213). PCV-15/PPSV-23 coverage was also significantly higher for blood isolates demonstrating clarithromycin resistance (60.4/75.1% blood, 47.8/57.4% respiratory; P ≤ 0.009) and penicillin resistance (68.9/63.0% blood, 45.2/43.0% respiratory; P < 0.0001) and trimethoprim/sulfamethoxazole-resistant isolates for PPSV-23 only (82.6% blood, 64.3% respiratory; P = 0.0057). Vaccine coverage was numerically higher but not significantly different between specimen source for children <2 years of age, as well as ceftriaxone-, doxycycline- and levofloxacin-resistant isolates. PCV-15/PPSV-23 vaccine coverage for MDR isolates (61.8%/67.3% blood, 52.2%/56.2% respiratory) and XDR isolates (93.3% blood, 89.6% respiratory for both vaccines) was not significantly different between specimen sources. CONCLUSIONS: PCV-15 and PPSV-23 serotype coverage is generally greater for blood versus respiratory isolates but not for MDR and XDR isolates. Continued pneumococcal surveillance is warranted to determine future trends in vaccine coverage, serotype distribution and antimicrobial susceptibilities under the pressure of vaccine use.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Antibacterianos/farmacologia , Criança , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Sistema Respiratório , Sorogrupo , Sorotipagem
18.
Viruses ; 14(1)2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-35062345

RESUMO

Rhinoviruses (RVs) have been reported as one of the main viral causes for severe respiratory illnesses that may require hospitalization, competing with the burden of other respiratory viruses such as influenza and RSV in terms of severity, economic cost, and resource utilization. With three species and 169 subtypes, RV presents the greatest diversity within the Enterovirus genus, and despite the efforts of the research community to identify clinically relevant subtypes to target therapeutic strategies, the role of species and subtype in the clinical outcomes of RV infection remains unclear. This review aims to collect and organize data relevant to RV illness in order to find patterns and links with species and/or subtype, with a specific focus on species and subtype diversity in clinical studies typing of respiratory samples.


Assuntos
Infecções por Picornaviridae/virologia , Rhinovirus/classificação , Rhinovirus/genética , Asma/etiologia , Coinfecção/virologia , Enterovirus , Infecções por Enterovirus/virologia , Técnicas de Genotipagem , Hospitalização , Humanos , Infecções Respiratórias/virologia , Sorotipagem
19.
J Infect Chemother ; 28(6): 806-809, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35078720

RESUMO

The widespread adoption of pneumococcal conjugate vaccines has reduced the incidence of Streptococcus pneumoniae infections, but has also led to the emergence of infections due to non-vaccine serotypes. A 15-month-old girl was referred to our hospital with suspected meningitis. S. pneumoniae was isolated from her cerebrospinal fluid. She was initially treated with a combination of cefotaxime and vancomycin, followed by ampicillin and vancomycin. After 7 days, the patient's condition improved and she was transferred to the general ward; however, her mother noted signs of hearing difficulties. On the 16th day of admission, we performed an auditory brainstem response test, which suggested severe bilateral hearing impairment. This was confirmed using an auditory steady-state response test after consulting with otolaryngologists. Magnetic resonance imaging revealed fibrosis of both cochleae with labyrinthitis. The patient underwent emergency cochlear implantation at a different hospital. The S. pneumoniae isolate was later identified to be serotype 10A with a PBP2x mutation, which is not covered by the conjugate vaccine and has reduced cephalosporin susceptibility. This case was characterized by highly rapid cochlear destruction, and an earlier otolaryngologist consultation may have provided a more well-organized surgery plan. Pediatricians are urged to promptly consult with otolaryngologists for patients with similar indications.


Assuntos
Meningite Pneumocócica , Infecções Pneumocócicas , Feminino , Humanos , Lactente , Meningite Pneumocócica/complicações , Meningite Pneumocócica/diagnóstico , Meningite Pneumocócica/tratamento farmacológico , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Sorogrupo , Sorotipagem , Streptococcus pneumoniae/genética , Vacinas Conjugadas/uso terapêutico , Vancomicina/uso terapêutico
20.
PLoS One ; 17(1): e0262225, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34986196

RESUMO

Pneumococcal conjugate vaccines reduce the burden of invasive pneumococcal disease, but the sustained effect of these vaccines can be diminished by an increase in disease caused by non-vaccine serotypes. To describe pneumococcal serotype epidemiology in Botswana following introduction of 13-valent pneumococcal conjugate vaccine (PCV-13) in July 2012, we performed molecular serotyping of 268 pneumococcal strains isolated from 221 children between 2012 and 2017. The median (interquartile range) age of the children included in this analysis was 6 (3,12) months. Fifty-nine percent of the children had received at least one dose of PCV-13 and 35% were fully vaccinated with PCV-13. While colonization by vaccine serotypes steadily declined following PCV-13 introduction, 25% of strains isolated more than 3 years after vaccine introduction were PCV-13 serotypes. We also observed an increase in colonization by non-vaccine serotypes 21 and 23B, which have been associated with invasive pneumococcal disease and antibiotic resistance in other settings.


Assuntos
Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/administração & dosagem , Sorotipagem/métodos , Streptococcus pneumoniae/classificação , Técnicas de Tipagem Bacteriana , Botsuana/epidemiologia , Feminino , Humanos , Lactente , Masculino , Nasofaringe/microbiologia , Filogenia , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas/farmacologia , Vigilância da População , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/genética
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