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2.
Ann Lab Med ; 43(1): 45-54, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36045056

RESUMO

Background: Streptococcus pneumoniae is a serious pathogen causing various infections in humans. We evaluated the serotype distribution and antimicrobial resistance of S. pneumoniae causing invasive pneumococcal disease (IPD) after introduction of pneumococcal conjugate vaccine (PCV)13 in Korea and investigated the epidemiological characteristics of multidrug-resistant (MDR) isolates. Methods: S. pneumoniae isolates causing IPD were collected from 16 hospitals in Korea between 2017 and 2019. Serotyping was performed using modified sequential multiplex PCR and the Quellung reaction. Antimicrobial susceptibility tests were performed using the broth microdilution method. Multilocus sequence typing was performed on MDR isolates for epidemiological investigations. Results: Among the 411 S. pneumoniae isolates analyzed, the most prevalent serotype was 3 (12.2%), followed by 10A (9.5%), 34 (7.3%), 19A (6.8%), 23A (6.3%), 22F (6.1%), 35B (5.8%), 11A (5.1%), and others (40.9%). The coverage rates of PCV7, PCV10, PCV13, and pneumococcal polysaccharide vaccine (PPSV)23 were 7.8%, 7.8%, 28.7%, and 59.4%, respectively. Resistance rates to penicillin, ceftriaxone, erythromycin, and levofloxacin were 13.1%, 9.2%, 80.3%, and 4.1%, respectively. MDR isolates accounted for 23.4% of all isolates. Serotypes 23A, 11A, 19A, and 15B accounted for the highest proportions of total isolates at 18.8%, 16.7%, 14.6%, and 8.3%, respectively. Sequence type (ST)166 (43.8%) and ST320 (12.5%) were common among MDR isolates. Conclusions: Non-PCV13 serotypes are increasing among invasive S. pneumoniae strains causing IPD. Differences in antimicrobial resistance were found according to the specific serotype. Continuous monitoring of serotypes and antimicrobial resistance is necessary for the appropriate management of S. pneumoniae infections.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas/farmacologia , Sorogrupo , Sorotipagem , Streptococcus pneumoniae/genética , Vacinas Conjugadas/farmacologia
3.
PLoS One ; 17(9): e0274558, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36107979

RESUMO

INTRODUCTION: Vaccination has dramatically reduced invasive Haemophilus influenzae type b (Hib) disease worldwide. Hib vaccination was introduced in the Lao PDR in 2009, as part of the pentavalent vaccine. To contribute to the understanding of the epidemiology of Hib in Lao PDR and the protection levels before and after the introduction of the vaccination, we tested serum samples from existing cohorts of vaccine age-eligible children and unvaccinated adolescents for antibodies against Hib. METHODS: Serum samples from 296 adolescents born before vaccine introduction and from 1017 children under 5 years (vaccinated and unvaccinated) were tested for anti-Hib antibodies by ELISA. Bivariate analyses were performed to investigate factors associated with long-term protection. RESULTS: The vast majority of all participants showed evidence of short- (42.7%) or long-term (56.1%) protection against Hib. Almost all of the unvaccinated adolescents had antibody titers indicating short-term protection and almost half (45.6%) were long-term protected. Nearly all children (>99.0%) were at least short-term protected, even those that were unvaccinated or whose vaccination status was unknown. Among vaccinated children, participants vaccinated more than 1 or 2 years ago and with a mid-upper arm circumference z-score < -2 were less likely to be long-term protected. DISCUSSION: Nearly all adolescents born before the introduction of Hib vaccination in the Lao PDR had antibody titers corresponding to at least short-term protection, indicating a high burden of Hib disease at that time. After vaccine introduction, all but four children (>99%) showed at least short-term protection. Possible explanations for the proportion of protected, yet apparently unvaccinated children, may be past infections, cross-reacting antibodies or faulty vaccination documentation. Our results highlight the need for robust surveillance and reporting of invasive Hib disease to determine the burden of disease despite vaccination.


Assuntos
Infecções por Haemophilus , Vacinas Anti-Haemophilus , Haemophilus influenzae tipo b , Adolescente , Anticorpos Antibacterianos , Antígenos de Bactérias , Antígenos Virais , Criança , Pré-Escolar , Infecções por Haemophilus/epidemiologia , Infecções por Haemophilus/prevenção & controle , Humanos , Laos/epidemiologia , Estudos Soroepidemiológicos , Sorogrupo , Vacinas Combinadas
4.
PLoS Negl Trop Dis ; 16(9): e0010740, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36067238

RESUMO

BACKGROUND: Invasive non-typhoidal Salmonella (iNTS-mainly serotypes Enteritidis and Typhimurium) are major causes of bloodstream infections in children in sub-Saharan Africa, but their reservoir remains unknown. We assessed iNTS carriage in rats in an urban setting endemic for iNTS carriage and compared genetic profiles of iNTS from rats with those isolated from humans. METHODOLOGY/PRINCIPAL FINDINGS: From April 2016 to December 2018, rats were trapped in five marketplaces and a slaughterhouse in Kisangani, Democratic Republic of the Congo. After euthanasia, blood, liver, spleen, and rectal content were cultured for Salmonella. Genetic relatedness between iNTS from rats and humans-obtained from blood cultures at Kisangani University Hospital-was assessed with multilocus variable-number tandem repeat (VNTR) analysis (MLVA), multilocus sequence typing (MLST) and core-genome MLST (cgMLST). 1650 live-capture traps yielded 566 (34.3%) rats (95.6% Rattus norvegicus, 4.4% Rattus rattus); 46 (8.1%) of them carried Salmonella, of which 13 had more than one serotype. The most common serotypes were II.42:r:- (n = 18 rats), Kapemba (n = 12), Weltevreden and Typhimurium (n = 10, each), and Dublin (n = 8). Salmonella Typhimurium belonged to MLST ST19 (n = 7 rats) and the invasive ST313 (n = 3, isolated from deep organs but not from rectal content). Sixteen human S. Typhimurium isolates (all ST313) were available for comparison: MLVA and cgMLST revealed two distinct rat-human clusters involving both six human isolates, respectively, i.e. in total 12/16 human ST313 isolates. All ST313 Typhimurium isolates from rats and humans clustered with the ST313 Lineage 2 isolates and most were multidrug resistant; the remaining isolates from rats including S. Typhimurium ST19 were pan-susceptible. CONCLUSION: The present study provides evidence of urban rats as potential reservoirs of S. Typhimurium ST313 in an iNTS endemic area in sub-Saharan Africa.


Assuntos
Infecções por Salmonella , Salmonella typhimurium , Animais , Criança , República Democrática do Congo/epidemiologia , Humanos , Tipagem de Sequências Multilocus , Ratos , Infecções por Salmonella/epidemiologia , Salmonella typhimurium/genética , Sorogrupo
5.
Science ; 377(6612): 1258-1259, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-36108015

RESUMO

A data-driven and policy-supported strategic use of aquifers for irrigation is needed to maximize their benefits.


Assuntos
Água Subterrânea , Água , Sorogrupo , Abastecimento de Água
6.
BMC Public Health ; 22(1): 1677, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-36064378

RESUMO

BACKGROUND: Invasive pneumococcal disease (IPD) is a major cause of pediatric morbidity and mortality. Pneumococcal conjugate vaccines (PCVs) were introduced in the US in 2000 (PCV7) and 2010 (PCV13). This study estimated the annual incidence rates (IRs) and time trends of IPD to quantify the burden of disease in children before and after the introduction of PCV7 and PCV13 in the US. METHODS: IPD episodes were identified in the IBM MarketScan Commercial and Medicaid Databases using claims with International Classification of Diseases 9/10th Revision, Clinical Modification codes. Annual IRs were calculated as the number of IPD episodes/100,000 person-years (PYs) for children < 18 years and by age group (< 2, 2-4, and 5-17 years). National estimates of annual IPD IRs were extrapolated using Census Bureau data. Interrupted time series (ITS) analyses were conducted to assess immediate and gradual changes in IPD IRs before and after introduction of PCV7 and PCV13. RESULTS: In commercially insured children, IPD IRs decreased from 9.4 to 2.8 episodes/100,000 PY between the pre-PCV7 (1998-1999) and late PCV13 period (2014-2018) overall, and from 65.6 to 11.6 episodes/100,000 PY in children < 2 years. In the Medicaid population, IPD IRs decreased from 11.3 to 4.2 episodes/100,000 PY between the early PCV7 (2001-2005) and late PCV13 period overall, and from 42.6 to 12.8 episodes/100,000 PY in children < 2 years. The trends of IRs for meningitis, bacteremia, and bacteremic pneumonia followed the patterns of overall IPD episodes. The ITS analyses indicated significant decreases in the early PCV7 period, increases in the late PCV7 and decreases in the early PCV13 period in commercially insured children overall. However, increases were also observed in the late PCV13 period in children < 2 years. The percentage of cases with underlying risk factors increased in both populations. CONCLUSIONS: IRs of IPD decreased from 1998 to 2018, following introduction of PCV7 and PCV13, with larger declines during the early PCV7 and early PCV13 periods, and among younger children. However, the residual burden of IPD remains substantial. The impact of future PCVs on IPD IRs will depend on the proportion of vaccine-type serotypes and vaccine effectiveness in children with underlying conditions.


Assuntos
Bacteriemia , Seguro , Infecções Pneumocócicas , Bacteriemia/epidemiologia , Criança , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Incidência , Lactente , Medicaid , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/uso terapêutico , Sorogrupo , Estados Unidos/epidemiologia , Vacinas Conjugadas
7.
Virol J ; 19(1): 141, 2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36064562

RESUMO

BACKGROUND: The development of the polymerase chain reaction (PCR) test promoted the evaluation of the epidemiological and clinical characteristics of human parainfluenza virus (HPIV) type 4, which has been rarely studied using conventional diagnostic methods. This study aimed to determine the seasonal epidemiological and clinical characteristics of all four HPIV serotypes (HPIV-1, HPIV-2, HPIV-3, and HPIV-4) during the era of PCR testing. METHODS: The medical records of hospitalized pediatric patients diagnosed with HPIV infections by a multiplex PCR test between 2015 and 2021 were retrospectively reviewed to determine the seasonal distributions of each HPIV serotype. For patients with a single HPIV infection, the clinical characteristics of each HPIV serotype were evaluated and compared with one another. RESULTS: Among the 514 cases of HPIV infection, HPIV-1, HPIV-2, HPIV-3, and HPIV-4 were identified in 27.2%, 11.9%, 42.6%, and 18.3% of cases, respectively. HPIV-3 was most prevalent in spring, and the other three serotypes were most prevalent in autumn. For patients with a single HPIV infection, those infected by HPIV-1 and HPIV-3 were younger than those infected by HPIV-2 and HPIV-4 (P < 0.001). Croup and lower respiratory tract infection (LRI) were most frequently diagnosed in patients infected by HPIV-1 (P < 0.001) and HPIV-4 (P = 0.002), respectively. During 2020-2021, HPIV-3 was most prevalent in autumn and caused fewer LRIs (P = 0.009) and more seizures (P < 0.001) than during 2015-2019. CONCLUSIONS: Each HPIV serotype exhibited a distinct seasonal predominance, and some differences in the clinical characteristics of the HPIV serotypes were observed. HPIV-4 acted as an important cause of LRI. Considering the recent changes in the epidemiological and clinical characteristics of HPIV-3, more time-series analyses should be conducted.


Assuntos
Infecções por Paramyxoviridae , Infecções Respiratórias , Criança , Humanos , Vírus da Parainfluenza 1 Humana , Vírus da Parainfluenza 2 Humana , Vírus da Parainfluenza 3 Humana , Vírus da Parainfluenza 4 Humana , Infecções Respiratórias/epidemiologia , Estudos Retrospectivos , Estações do Ano , Sorogrupo
8.
Clin Lab ; 68(9)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36125139

RESUMO

BACKGROUND: Salmonella is composed of a wide variety of serovars that cause human self-limited gastrointestinal illnesses or invasive infections. Most of the Salmonella strains of clinical isolates belong to the A - F group. In December 2012, a case of invasive infection was caused by a rare Salmonella, Salmonella enterica serovar Moualine (S. Moualine), identified as 047 outside of groups A - F, which was easily missed or misreported. The goal is to ex-plore clinical symptoms and therapies of blood infection caused by S. Moualine and to provide theoretical basis and molecular level date for Salmonella research by analyzing pathogenic characteristics and genome information of S. Moualine. METHODS: The S. Moualine genome was sequenced using a PacBio RS II platform and Illumina HiSeq 4000 platform and analysis for serotyping serovars, ST types, the characterization of antibiotic resistance, virulence and phylogeny. RESULTS: The clinical symptoms were mainly irregular recurrent fever, lasting 1 - 3 weeks, with mild gastrointestinal symptoms. The genome size of S. Moualine was 4,611,151 bp, the serotype was 047 (+), Hy (+), H1,6 (+), and multilocus sequence typing analysis was ST3038. S. Moualine contains the majority of virulence genes. Interestingly, S. Moualine also harbors the rck and Typhi colonization factor (tcf) genes, which may play a role in invasive infection. S. Moualine encodes 17 Salmonella pathogenicity islands and is potentially dangerous to human health. Both phenotypic and genomic characterizations have demonstrated that S. Moualine generally showed low antimicrobial resistance potential. CONCLUSIONS: There were few reports on S. Moualine. According to clinical symptoms and genetic analysis, S. Moualine was predicted to be a highly virulent bacteria and was also potentially dangerous to health of humans. This study highlights that the transparency of global surveillance genomic data could accelerate the understanding of the virulence and antimicrobial resistance makeup of a previously unknown threat.


Assuntos
Anti-Infecciosos , Salmonella enterica , Genômica , Humanos , Salmonella/genética , Salmonella enterica/genética , Sorogrupo
10.
Vaccine ; 40(41): 5950-5958, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36075797

RESUMO

BACKGROUND: Limited data are available on long-term indirect effects of ten-valent pneumococcal conjugate vaccine (PCV10) programmes. We evaluated changes in invasive pneumococcal disease (IPD) incidence, mortality, and serotype distribution in adults up to 9 years after infant PCV10 introduction. METHODS: Culture-confirmed IPD cases ≥18 years (n = 5610; 85% were pneumonia) were identified through national, population-based laboratory surveillance; data were linked with population registry to conduct nationwide follow-up study. In a time-series model, we compared serotype-specific IPD incidence and associated 30-day mortality rates before and after PCV10 by using negative binomial regression models. RESULTS: During pre-PCV10 period (7/2004-6/2010), overall IPD incidence in adults ≥18 years increased yearly by 4.8%. After adjusting for trend and seasonality, the observed PCV10 serotype IPD incidence in 7/2018-6/2019 was 90% (12/100,000 person-years) lower than the expected rate without PCV10 program. Non-PCV10 serotype incidence was 40% (4.4/100,000 person-years) higher than expected; serotypes 3, 19A, 22F, and 6C accounted for most of the rate increase. However, incidence of non-PCV10 IPD levelled off by end of follow-up. The observed-expected incidence rate-ratio (IRR) was 0·7 (95 %CI 0·5-0.8) for all IPD and 0·7 (95 %CI 0·3-1·3) for IPD-associated 30-day mortality. Case-fatality proportion decreased from 11·9% to 10.0% (p < 0.01). In persons ≥65 years, the IRR was 0·7 (95 %CI 0·5-0.95). CONCLUSIONS: Significant indirect effects were seen for vaccine-serotype IPD and for overall IPD in all adult age groups. For non-vaccine IPD, the incidence stabilized 5 years after infant PVC10 program introduction, resulting in a steady state in which non-vaccine IPD accounted for nearly 90% of overall IPD. Substantial pneumococcal disease burden remains in older adults.


Assuntos
Infecções Pneumocócicas , Idoso , Finlândia/epidemiologia , Seguimentos , Humanos , Incidência , Lactente , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Sorogrupo , Vacinação , Vacinas Conjugadas
11.
J Vector Borne Dis ; 59(2): 109-114, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36124476

RESUMO

BACKGROUND & OBJECTIVES: Dengue virus (DENV) is an RNA virus that infects approximately 2.5 billion people around the world. The incidence of dengue fever has rapidly increased at an alarming rate in the last few years and has affected thousands of people in Pakistan. This review explores the prevalence, serotypes and pathogenesis of dengue virus circulating in Pakistan. METHODS: A systematic review of observational studies published between 1994 and December 2019 was performed. All records of the confirmed outbreak of dengue fever in Pakistan were reviewed and articles containing no primary data were excluded. RESULTS: Four identified serotypes of dengue virus (DENV 1-4) circulate in different regions of the world causing epidemics. The most prevalent serotype, which is still epidemic and dominant in Pakistan, is DENV-2. Many factors like over-population, rapid urbanization, travelling, lack of vector control in dengue endemic areas and inadequate health-care are responsible of dynamic and huge raise of dengue in Pakistan. INTERPRETATION & CONCLUSION: Currently there is no specific treatment for prevention of dengue virus. Recently some antiviral compounds were being tested to eradicate this disease. There is a need to develop an efficient and safe vaccine for all four serotypes to combat dengue viral infection globally and particularly in Pakistan.


Assuntos
Vírus da Dengue , Dengue , Antivirais , Dengue/epidemiologia , Dengue/prevenção & controle , Vírus da Dengue/genética , Humanos , Paquistão/epidemiologia , Sorogrupo
12.
An Acad Bras Cienc ; 94(3): e20201026, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36074401

RESUMO

Leptospirosis is an important public health problem caused by Leptospira. The objective is to characterize the geographic distribution of pathogenic leptospira serovars in the Americas through a systematic review of the literature between 1930-2017. Searches were conducted in six scientific databases (PubMed, Web of Science, Embase, Lilacs, Scopus and Cochrane). We included studies conducted unambiguously in the Americas, that investigated infection of Leptospira in humans and animals in their natural environments with serovar identification. 283 articles were included, of which 69 were studies in humans, 86 in wild animals, and 182 in domestic animals. Most of them conducted in Brazil (104, 36.7%) and in rural environments (158, 55.8%). Bovines, equines and dogs where the most frequently studied domestic species. However, a large diversity including 80 species of wild animals were studied. Icterohaemorrhgiae, Canicola, Pomona and Grippotyphosa were the most common serovars, described in 46 (16.2%), 38 (13.3%), 32 (11.3%) and 26 (9%) of the articles, respectively. The Results indicate a large concentration of studies in Latin America, with emphasis on Brazil, in wild mammals and three main domestic animal groups. Our results emphasize the need for studies that delve into the relationships of the epidemiological cycle, environment, and health.


Assuntos
Leptospira , Leptospirose , Animais , Animais Selvagens , Anticorpos Antibacterianos , Brasil/epidemiologia , Bovinos , Cães , Equidae , Humanos , Leptospirose/epidemiologia , Leptospirose/veterinária , Sorogrupo
13.
Food Microbiol ; 108: 104112, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36088119

RESUMO

Salmonella spp. remains one of the main pathogens causing diarrhea in humans worldwide. Lately, Salmonella Infantis has become endemic in several European, American, and Asian countries, presenting a multi-drug resistance profile and increased virulence. Various studies have attributed the high endemicity of Salmonella Infantis to pESI (plasmid to Emergent Salmonella Infantis). The ease of Salmonella to acquire pESI is of concern to health authorities and the food production chain. We searched for the presence of pESI in Salmonella genomes from the NCBI to understand the distribution of pESI worldwide and predict the main serovars and sequence types associated with the plasmid. We identified the pESI backbone, virulence, and resistance genes among Salmonella spp. isolated from 45 countries on five continents. We found the pESI-like structure in four different serovars: S. Muenchen, S. Schwarzengrund, S. Agona and S. Senftenberg. The pESI markers were also identified in 24 different sequence types. Most of the analyzed genomes were isolated from poultry, especially broiler and chicken. These results confirm the high dissemination of pESI-like megaplasmid among Salmonella Infantis worldwide and its ability to infect different serovars, as well as placing poultry production as the most favorable environment for pESI dissemination. Therefore, further studies are needed to prevent the spread of pESI to humans and the food chain.


Assuntos
Salmonelose Animal , Salmonella enterica , Animais , Galinhas , Genômica , Humanos , Aves Domésticas , Salmonella/genética , Salmonelose Animal/epidemiologia , Salmonella enterica/genética , Sorogrupo
14.
PLoS One ; 17(9): e0274362, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36129918

RESUMO

BACKGROUND: Leptospirosis causes significant economic losses and is an occupational risk in the swine industry, especially in developing tropical regions where social and geoclimatic conditions are favorable for the transmission of this disease. Although vaccination can reduce infection risk, efficacy is diminished if local genetic and antigenic variants of the pathogen are not accounted for in the vaccine. Identifying and characterizing strains hosts, and potential mechanisms of transmission is therefore critical for public health mitigation practices. METHODOLOGY/PRINCIPAL FINDINGS: Our study was conducted on a rural breeding farm in Ecuador, where we used a PCR assay that targets lipL32 to detect Leptospira spp. and targeted gene sequencing to identify Leptospira santarosai in the kidneys, testicles, and ejaculate of a vaccinated boar. MAT results showed low titers against serovars found in the vaccine, but the MAT panel did not include serovars of L. santarosai. The boar showed no symptoms of leptospirosis but did show blood in the semen. However, no postmortem histopathological lesions were observed tissue samples. Vaccinated sows that were artificially inseminated with the semen from this boar had reproductive problems, suggesting that transmission had occurred. This is the first documented case of Leptospira santarosai in the reproductive tract of a boar. CONCLUSIONS/SIGNIFICANCE: As L. santarosai is pathogenic in other livestock species and humans, our finding highlights the need to evaluate the prevalence and epidemiological significance of this pathogen in livestock and consider the possibility of venereal transmission. In addition, further studies are needed to identify and characterize local serovars that may impact diagnosis and vaccination programs to better control leptospirosis in livestock and spillover into the human population.


Assuntos
Leptospira , Leptospirose , Animais , Feminino , Humanos , Leptospira/genética , Leptospirose/epidemiologia , Leptospirose/prevenção & controle , Leptospirose/veterinária , Gado , Masculino , Saúde Pública , Sorogrupo , Suínos
15.
BMC Pediatr ; 22(1): 557, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36131275

RESUMO

BACKGROUND/SIGNIFICANCE: Salmonella gastroenteritis causes significant morbidity among pediatric patients, mainly in developing world, such as the Middle East and North Africa (MENA) region. Concurrently, data from MENA countries like Iran, regarding prevalence of Salmonella serotypes, antimicrobial susceptibility, and biofilm production is scarce. MATERIAL & METHODS: Slide agglutination was used to determine the serogroup of 140 Salmonella isolates recovered from 4477 stool specimens collected from children with gastroenteritis, and isolates were serotyped by PCR assay. The antimicrobial susceptibility of isolates to five first line drugs was assessed by disk diffusion assay using CLSI guidelines. Semi-quantitative evaluation of biofilm production was done by microtiter plate assay followed by PCR detection of biofilm-associated virulence genes csgD, pefA, and bcsA for each isolate. RESULTS: Nearly 94% of Salmonella isolates were recovered from ≤ 5-year-old patients, and 99% of isolates were non-typhoidal. While we found extensive diversity among Salmonella isolates, serogroup D (46%) predominated, and Salmonella Enteritidis (41%) was the most common serotype that showed the highest antimicrobial susceptibility rate (> 96%). For the first time in Iran, S. Newport serotype from human specimens was isolated. Most isolates were sensitive to all test antimicrobials, but 35% of isolates were not-typed (NT) that showed the highest resistance with 48% being resistant to ≥ 1 test antimicrobial. Majority of isolates made weak (or no) biofilm, and we found a weak association between antimicrobial susceptibility, biofilm production, or virulence genes csgD, pefA, and bcsA. CONCLUSIONS: The most effective measure that may control pediatric salmonellosis outbreaks is raising awareness of parents of preschoolers about food safety. Isolation of highly diverse Salmonella serotypes, including many commonly isolated from animals, indicates widespread contamination of the food chain. Majority of serotypes were sensitive to first-line antimicrobials, thus presently, pediatric Salmonella infections in this region may be controlled by conventional antimicrobials. However, despite the current trend, an imminent emergence of resistant Salmonella strains is foreseen, since various serotypes resistant to > 1 antimicrobial agent are typically associated with animals. Our results warrant further investigation that includes correlation analysis of clinical data regarding treatment outcomes, and serotype attributes like virulence genes.


Assuntos
Anti-Infecciosos , Gastroenterite , Infecções por Salmonella , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos/farmacologia , Biofilmes , Criança , Pré-Escolar , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana Múltipla/genética , Humanos , Irã (Geográfico)/epidemiologia , Testes de Sensibilidade Microbiana , Salmonella/genética , Infecções por Salmonella/tratamento farmacológico , Infecções por Salmonella/epidemiologia , Sorogrupo , Virulência/genética
16.
Methods Mol Biol ; 2573: 89-113, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36040589

RESUMO

Adeno-associated virus serotype 9 (AAV9) is often used in heart research involving gene delivery due to its cardiotropism, high transduction efficiency, and little to no pathogenicity, making it highly applicable for gene manipulation, in vivo. However, current AAV9 technology is limited by the lack of strains that can selectively express and elucidate gene function in an atrial- and ventricular-specific manner. In fact, study of gene function in cardiac atria has been limited due to the lack of an appropriate tool to study atrial gene expression in vivo, hindering progress in the study of atrial-specific diseases such as atrial fibrillation, the most common cardiac arrhythmia in the USA.This chapter describes the method for the design and production of such chamber-specific AAV9 vectors, with the use of Nppa and Myl2 promoters to enhance atrial- and ventricular-specific expression. While several gene promoter candidates were considered and tested, Nppa and Myl2 were selected for use here because of their clearly defined regulatory elements that confer cardiac chamber-specific expression. Accordingly, Nppa (-425/+25) and Myl2 (-226/+36) promoter fragments are inserted into AAV9 vectors. The atrial- and ventricular-specific expression conferred by these new recombinant AAV9 was confirmed in a double-fluorescent Cre-dependent reporter mouse model. At only 450 and 262 base pairs of Nppa and Myl2 promoters, respectively, these AAV9 that drive chamber-specific AAV9 transgene expression address two major limitations of AAV9 technology, i.e., achieving chamber-specificity while maximizing space in the AAV genome for insertion of larger transgenes.


Assuntos
Dependovirus , Vetores Genéticos , Animais , Dependovirus/genética , Dependovirus/metabolismo , Técnicas de Transferência de Genes , Vetores Genéticos/genética , Átrios do Coração/metabolismo , Camundongos , Sorogrupo
17.
Methods Mol Biol ; 2573: 293-304, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36040603

RESUMO

The field of cardiac gene therapy has seen the rising use of adeno-associated viral (AAV) vectors as a promising therapeutic option for cardiac diseases and heart failure. To achieve intended results of AAV delivery, a majority of clinical studies screen patients for existing neutralizing antibodies that could inhibit the effects of the administered AAV and confound treatment efficacy. The cell-based neutralizing antibody assay offers a method of quantifying and identifying a patient's existing neutralizing antibodies against specific serotypes. Combined with the luciferase assay, the neutralizing antibody assay tests the ability of patient antibodies in the blood to prevent gene transduction of AAV-encoded luciferase gene at ranging serial dilutions. This chapter provides a protocol and experimental techniques to determine the presence of neutralizing antibodies against AAV in the blood.


Assuntos
Anticorpos Neutralizantes , Dependovirus , Anticorpos Antivirais , Dependovirus/genética , Terapia Genética/métodos , Vetores Genéticos/genética , Humanos , Sorogrupo
18.
Microb Genom ; 8(8)2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35930328

RESUMO

Approximately 200 O-serogroups of Vibrio cholerae have already been identified; however, only 2 serogroups, O1 and O139, are strongly related to pandemic cholera. The study of non-O1 and non-O139 strains has hitherto been limited. Nevertheless, there are other clinically and epidemiologically important serogroups causing outbreaks with cholera-like disease. Here, we report a comprehensive genome analysis of the whole set of V. cholerae O-serogroup reference strains to provide an overview of this important bacterial pathogen. It revealed structural diversity of the O-antigen biosynthesis gene clusters located at specific loci on chromosome 1 and 16 pairs of strains with almost identical O-antigen biosynthetic gene clusters but differing in serological patterns. This might be due to the presence of O-antigen biosynthesis-related genes at secondary loci on chromosome 2.


Assuntos
Cólera , Vibrio cholerae , Cólera/epidemiologia , Cólera/microbiologia , Cromossomos , Genômica , Humanos , Antígenos O/genética , Sorogrupo , Vibrio cholerae/genética
19.
Front Cell Infect Microbiol ; 12: 941867, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992162

RESUMO

Phage therapy is a promising alternative treatment of bacterial infections in human and animals. Nevertheless, despite the appearance of many bacterial strains resistant to antibiotics, these drugs still remain important therapeutics used in human and veterinary medicine. Although experimental phage therapy of infections caused by Salmonella enterica was described previously by many groups, those studies focused solely on effects caused by bacteriophages. Here, we compared the use of phage therapy (employing a cocktail composed of two previously isolated and characterized bacteriophages, vB_SenM-2 and vB_Sen-TO17) and antibiotics (enrofloxacin and colistin) in chickens infected experimentally with S. enterica serovar Typhimurium. We found that the efficacies of both types of therapies (i.e. the use of antibiotics and phage cocktail) were high and very similar to one another when the treatment was applied shortly (one day) after the infection. Under these conditions, S. Typhimurium was quickly eliminated from the gastrointestinal tract (GIT), to the amount not detectable by the used methods. However, later treatment (2 or 4 days after detection of S. Typhimurium in chicken feces) with the phage cocktail was significantly less effective. Bacteriophages remained in the GIT for up to 2-3 weeks, and then were absent in feces and cloaca swabs. Interestingly, both phages could be found in various organs of chickens though with a relatively low abundance. No development of resistance of S. Typhimurium to phages or antibiotics was detected during the experiment. Importantly, although antibiotics significantly changed the GIT microbiome of chickens in a long-term manner, analogous changes caused by phages were transient, and the microbiome normalized a few weeks after the treatment. In conclusion, phage therapy against S. Typhimurium infection in chickens appeared as effective as antibiotic therapy (with either enrofloxacin or colistin), and less invasive than the use the antibiotics as fewer changes in the microbiome were observed.


Assuntos
Bacteriófagos , Terapia por Fagos , Salmonelose Animal , Salmonella enterica , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Galinhas , Colistina/farmacologia , Enrofloxacina/farmacologia , Salmonelose Animal/microbiologia , Salmonelose Animal/terapia , Salmonella typhimurium , Sorogrupo
20.
mSphere ; 7(4): e0011422, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35913133

RESUMO

Streptococcus pneumoniae is a major cause of community-acquired pneumonia (CAP) in young children, older adults, and those with immunocompromised status. Since the introduction of pneumococcal vaccines, the burden of invasive pneumococcal disease caused by vaccine serotypes (STs) has decreased; however, the effect on the burden of CAP is unclear, potentially due to the lack of testing for pneumococcal STs. We describe the development, qualification, and clinical validation of a high-throughput and multiplex ST-specific urine antigen detection (SSUAD) assay to address the unmet need in CAP pneumococcal epidemiology. The SSUAD assay is sensitive and specific to the 15 STs in the licensed pneumococcal conjugate vaccine V114 (STs 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 22F, 23F, and 33F) and uses ST-specific monoclonal antibodies for rapid and simultaneous quantification of the 15 STs using a Luminex microfluidics system. The SSUAD assay was optimized and qualified using healthy adult urine spiked with pneumococcal polysaccharides and validated using culture-positive clinical urine samples (n = 34). Key parameters measured were accuracy, precision, sensitivity, specificity, selectivity, and parallelism. The SSUAD assay met all prespecified validation acceptance criteria and is suitable for assessments of disease burden associated with the 15 pneumococcal STs included in V114. IMPORTANCE Streptococcus pneumoniae has more than 90 serotypes capable of causing a range of disease manifestations, including otitis media, pneumonia, and invasive diseases, such as bacteremia or meningitis. Only a minority (<10%) of pneumococcal diseases are bacteremic with known serotype distribution. Culture and serotyping of respiratory specimens are neither routine nor reliable. Hence, the serotype-specific disease burden of the remaining (>90%) noninvasive conditions is largely unknown without reliable laboratory techniques. To address this need, a 15-plex urine antigen detection assay was developed and validated to quantify pneumococcal serotype-specific capsular polysaccharides in urine. This assay will support surveillance to estimate the pneumococcal disease burden and serotype distribution in nonbacteremic conditions. Data obtained from this assay will be critical for understanding the impact of pneumococcal vaccines on noninvasive pneumococcal diseases and to inform the choice of pneumococcal serotypes for next-generation vaccines.


Assuntos
Bacteriemia , Infecções Comunitárias Adquiridas , Infecções Pneumocócicas , Pneumonia , Idoso , Criança , Pré-Escolar , Humanos , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas , Polissacarídeos , Sorogrupo , Streptococcus pneumoniae
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