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1.
Antibiotics (Basel) ; 13(5)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38786118

RESUMEN

Group B Streptococcus (GBS) is a major cause of contagious bovine mastitis (CBM) in Brazil. The GBS population is composed of host-generalist and host-specialist lineages, which may differ in antimicrobial resistance (AMR) and zoonotic potential, and the surveillance of bovine GBS is crucial to developing effective CBM control and prevention measures. Here, we investigated bovine GBS isolates (n = 156) collected in Brazil between 1987 and 2021 using phenotypic testing and whole-genome sequencing to uncover the molecular epidemiology of bovine GBS. Clonal complex (CC) 61/67 was the predominant clade in the 20th century; however, it was replaced by CC91, with which it shares a most common recent ancestor, in the 21st century, despite the higher prevalence of AMR in CC61/67 than in CC91, and high selection pressure for AMR from indiscriminate antimicrobial use in the Brazilian dairy industry. CC103 also emerged as a dominant CC in the 21st century, and a considerable proportion of herds had two or more GBS strains, suggesting poor biosecurity and within-herd evolution due to the chronic nature of CBM problems. The majority of bovine GBS belonged to serotype Ia or III, which was strongly correlated with CCs. Ninety-three isolates were resistant to tetracycline (≥8 µg/mL; tetO = 57, tetM = 34 or both = 2) and forty-four were resistant to erythromycin (2.0 to >4 µg/mL; ermA = 1, ermB = 38, mechanism unidentified n = 5). Only three isolates were non-susceptible to penicillin (≥8.0 µg/mL), providing opportunities for improved antimicrobial stewardship through the use of narrow-spectrum antimicrobials for the treatment of dairy cattle. The common bovine GBS clades detected in this study have rarely been reported in humans, suggesting limited risk of interspecies transmission of GBS in Brazil. This study provides new data to support improvements to CBM and AMR control, bovine GBS vaccine design, and the management of public health risks posed by bovine GBS in Brazil.

3.
Antibiotics (Basel) ; 13(1)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38247643

RESUMEN

Streptococcus agalactiae (Group B Streptococcus; GBS) is a leading cause of neonatal invasive disease worldwide. GBS can colonize the human gastrointestinal and genitourinary tracts, and the anovaginal colonization of pregnant women is the main source for neonatal infection. Streptococcus anginosus, in turn, can colonize the human upper respiratory, gastrointestinal, and genitourinary tracts but has rarely been observed causing disease. However, in the last years, S. anginosus has been increasingly associated with human infections, mainly in the bloodstream and gastrointestinal and genitourinary tracts. Although anovaginal screening for GBS is common during pregnancy, data regarding the anovaginal colonization of pregnant women by S. anginosus are still scarce. Here, we show that during the assessment of anovaginal GBS colonization rates among pregnant women living in Rio de Janeiro, Brazil, S. anginosus was also commonly detected, and S. anginosus isolates presented a similar colony morphology and color pattern to GBS in chromogenic media. GBS was detected in 48 (12%) while S. anginosus was detected in 17 (4.3%) of the 399 anovaginal samples analyzed. The use of antibiotics during pregnancy and history of urinary tract infections and sexually transmitted infections were associated with the presence of S. anginosus. In turn, previous preterm birth was associated with the presence of GBS (p < 0.05). The correlation of GBS and S. anginosus with relevant clinical features of pregnant women in Rio de Janeiro, Brazil, highlights the need for the further investigation of these important bacteria in relation to this special population.

6.
Pathogens ; 11(10)2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36297161

RESUMEN

Group B Streptococcus (GBS) is a leading cause of neonatal infections. The genitourinary and gastrointestinal tract of pregnant women are the main source of transmission to newborns. This work investigated the prevalence and characterized GBS from pregnant women in Rio de Janeiro, Brazil, comparing the periods before (January 2019 to March 2020; 521) and during (May 2020 to March 2021; 285) the COVID-19 pandemic. GBS was detected in 10.8% of anovaginal samples. Considering scenarios before and during the pandemic, GBS colonization rate significantly decreased (13.8% vs. 5.3%; p = 0.0001). No clinical and sociodemographic aspect was associated with GBS carriage (p > 0.05). A total of 80%, 13.8% and 4.6% GBS strains were non-susceptible to tetracycline, erythromycin and clindamycin, respectively. Serotype Ia was the most frequent (47.7%), followed by V (23.1%), II (18.4%), III (7.7%) and Ib (3.1%). An increasing trend of serotypes Ib and V, as well as of antimicrobial resistance rates, and a decreasing trend of serotypes II and III, were observed after the pandemic onset, albeit not statistically significant (p > 0.05). The reduction in GBS colonization rates and alterations in GBS serotypes and resistance profiles during the pandemic were not due to changes in the sociodemographic profile of the population. Considering that control and preventive measures related to the COVID-19 pandemic onset have impacted other infectious diseases, these results shed light on the need for the continuous surveillance of GBS among pregnant women in the post-pandemic era.

7.
Microb Drug Resist ; 28(5): 517-524, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35263182

RESUMEN

Streptococcus agalactiae (Group B Streptococcus , GBS) is a major agent of perinatal infections. Biofilms have been associated with GBS colonization and disease, as well as with infection persistence and recurrence. Although GBS remains susceptible to beta-lactams, it is still unknown how sessile cells respond to these antibiotics. Here, we evaluated the effect of different concentrations of penicillin (3-48 mg/L) on in vitro biofilm formation by four GBS strains belonging to serotype Ia/clonal complexes23 that were recovered from the oropharynx or urine of pregnant women and were previously characterized as strong biofilm producers. All four GBS strains were fully susceptible to penicillin (minimum inhibitory concentration = 0.023 mg/L), but penicillin was not able to fully prevent biofilm formation by these GBS strains. Biofilms formed in the presence of penicillin had reduced biomasses and thickness, but they were still classified as strong. Penicillin significantly reduced the density of live cells, but higher penicillin concentrations did not lead to improved prevention of biofilm formation. Biofilms formed in the presence of penicillin had no channels or long cocci chains observed in penicillin-free biofilms. Overall, results highlight the concerning possible impacts of biofilm formation in penicillin-based treatment and preventive strategies of GBS infections, even when the bacterial strain involved is fully antibiotic-susceptible.


Asunto(s)
Infecciones Estreptocócicas , Streptococcus agalactiae , Antibacterianos/farmacología , Biopelículas , Femenino , Humanos , Pruebas de Sensibilidad Microbiana , Penicilinas/farmacología , Embarazo , Serogrupo , Infecciones Estreptocócicas/tratamiento farmacológico , Infecciones Estreptocócicas/microbiología
9.
Braz J Microbiol ; 52(3): 1631-1635, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34164798

RESUMEN

Group B Streptococcus (GBS) is a leading cause of human neonatal infections and bovine mastitis. We report here the unusual finding of the human-adapted hypervirulent serotype III/ST17 clone in a bovine GBS isolated in 1987 in Brazil. This isolate shared several phenotypic and genotypic characteristics with serotype III/ST17 strains obtained from human sources, including PFGE pattern, pilus genes, lactose fermentation, DNase activity, and antimicrobial susceptibility profile, highlighting the importance of continued tracking of GBS in the One Health scope. The study brings new evidence for the potential interspecies transmission and sheds new light into evolution aspects of the pathogen Group B Streptococcus (GBS) by reporting the occurrence of an ancient bovine GBS isolate belonging to a variant currently known to be exclusively found in human hosts.


Asunto(s)
Infecciones Estreptocócicas , Streptococcus agalactiae , Animales , Brasil , Bovinos/microbiología , Células Clonales , Femenino , Humanos , Serogrupo , Infecciones Estreptocócicas/veterinaria , Streptococcus agalactiae/genética
10.
Artículo en Inglés | MEDLINE | ID: mdl-33953817

RESUMEN

DivulgaMicro is a Brazilian science communication and outreach project run by three young female scientists. In 2020, due to the COVID-19 pandemic, we promoted the first virtual edition of the DivulgaMicro Workshop. Here, we describe adaptations implemented to deliver the virtual edition and its assessment by the participants. We offered a 3-day workshop addressing manuscript writing and publishing, poster design and oral presentations, and strategies for effectively communicating with the lay public on Days 1, 2, and 3, respectively. Each daily session was divided into short lectures and active learning through interactive and cooperative activities. We applied pre- and postsession surveys daily to assess participants' learning, with an opinion questionnaire at the end of the workshop. We selected 50 of 221 applicants, but only 38 of those selected participated in the workshop. Correct answers were significantly higher (p < 0.01) in the postsession surveys each day. Most of the 34 participants who answered the opinion questionnaire (97%) would recommend the workshop to their colleagues. Participants stated that the workshop content was transmitted in a clear and straightforward manner, and they considered the online format suitable for knowledge acquisition. Participants were satisfied with the organization, dynamics, and interactivity. Topics addressed on Day 3 (61.8%) and Day 1 (23.5%) were most liked and were considered most useful in the participants' careers. We believe that the overall success of the workshop is due to the combination of short lectures with active-learning activities, the use of virtual platforms that enabled effective communication between participants and instructors, and the support of our collaborators.

12.
Biofouling ; 35(8): 938-944, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31646898

RESUMEN

Streptococcus agalactiae (group B Streptococcus, GBS) is a major pathogen in humans and animals. Pili and biofilm may be important virulence factors in this bacterial species. Here, biofilm production and the distribution of pilus variants among 134 GBS isolates from human and animal sources were evaluated. Biofilm production was significantly enhanced in 1% glucose-supplemented medium (p < 0.05). Using this medium, most GBS strains were strong biofilm producers. Biomass was mainly composed of proteins, followed by extracellular DNA, while polysaccharides represented a minor portion. All GBS strains presented at least one pilus variant. PI-2a was the most common among human GBS while PI-2b was the most common among animal isolates. Human GBS harboring PI-2b and animal GBS harboring PI-2a presented significantly reduced biofilm production (p = 0.0033). In conclusion, strong biofilm production seems to be a common characteristic in GBS, and association of the clinical source with the pilus variant may be crucial for this.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Fimbrias Bacterianas/genética , Infecciones Estreptocócicas/microbiología , Streptococcus agalactiae/aislamiento & purificación , Animales , Proteínas Bacterianas/genética , ADN Bacteriano , Variación Genética , Humanos , Streptococcus agalactiae/genética , Streptococcus agalactiae/crecimiento & desarrollo , Factores de Virulencia/genética
13.
Artículo en Inglés | MEDLINE | ID: mdl-31160934

RESUMEN

Communication is fundamental in science. Among scientists, communication skills are required to write a comprehensible scientific manuscript or to prepare an attractive oral presentation. In addition, the ability to communicate successfully with the nonscientific community has been increasingly appreciated, as it represents the most effective way to promote popular scientific literacy. Nevertheless, students majoring in sciencerelated courses are not trained specifically for these purposes, and improving communication skills usually depends on tips and advice given by peers. To this end, we have launched DivulgaMicro, an initiative that aims to enhance science communication among early-career scientists in Brazil. DivulgaMicro relies on two major cornerstones: providing online resources via a dedicated website (www.divulgamicro.com.br/index.html) and promoting onsite workshops in universities located in different macro regions of the country. On the website, people can access a collection of fun activities designed to teach scientific concepts to a general audience, along with tips and news regarding public outreach events in Brazil. In the month following its launch, our website had 1,026 visitors from 10 different countries besides Brazil. Regarding the workshops, six were offered during 2018, with nearly 600 attendees. In the course, scientists are presented best practices for scientific writing and oral presentations, as well as techniques to improve communication with lay audiences, such as the use of storytelling structure and analogies. There is a high demand for science communication resources in Brazil, attesting to the importance of initiatives such as DivulgaMicro in our country.


A comunicação é fundamental para a ciência e a comunidade científica, cuja habilidade em se comunicar é necessária tanto para a escrita de um artigo científico quanto para a preparação de uma apresentação oral atrativa. Além disso, a capacidade de se comunicar de forma bem-sucedida com o público leigo tem sido cada vez mais apreciada, uma vez que representa a maneira mais eficaz em promover a alfabetização científica da população. No entanto, os estudantes que buscam se engajar na carreira científica não recebem treinamento específico nesse sentido, e o desenvolvimento dessa habilidade geralmente é dependente de dicas e conselhos recebidos de seus pares. Nesse contexto, foi criado o projeto DivulgaMicro, uma iniciativa que visa promover o desenvolvimento da comunicação científica entre jovens cientistas no Brasil. O projeto DivulgaMicro possui dois pilares principais: oferecer recursos online através do website http://www.divulgamicro.com.br/index.html e promover workshops de Comunicação e Divulgação Científica em universidades de diferentes macrorregiões do país. No website, as pessoas podem acessar e baixar uma coleção de atividades lúdicas destinadas ao ensino de conceitos científicos para o público em geral, incluindo crianças e adolescentes, além de dicas e novidades sobre divulgação científica no país. Após um mês de lançamento do projeto, o website do DivulgaMicro já havia recebido 1.026 acessos de 10 diferentes países além do Brasil. Em relação aos workshops, estão previstas seis edições em 2018 alcançando um público de cerca de 800 pessoas. No workshop, o participante é apresentado às melhores e mais eficazes práticas de escrita científica e apresentação oral, bem como técnicas para desenvolver e aprimorar a comunicação com o público leigo, incluindo como utilizar a estrutura storytelling e a aplicação de analogias. Atualmente no Brasil existe uma alta demanda em recursos e fontes de aprendizado em comunicação e divulgação científica, o que corrobora a relevância de iniciativas como o DivulgaMicro em nosso país.

14.
Front Microbiol ; 10: 486, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30930879

RESUMEN

Streptococcus pneumoniae is a major cause of community-acquired pneumonia and meningitis, and it is also found as a commensal, colonizing the human upper respiratory tract of a portion of the human population. Its polysaccharide capsule allows the recognition of more than 90 capsular types and represents the target of the currently available pneumococcal conjugate vaccines (PCVs), such as the 10-valent (PCV10) and the 13-valent (PCV13). Penicillin non-susceptible pneumococci (PNSP) have been listed as one of the current major antimicrobial-resistant pathogen threats. In Brazil, the emergence of PNSP was initially detected in the mid 1990s and PCV10 has been part of the National Immunization Program since 2010. Here, we investigated the distribution of capsular types and penicillin susceptibility profiles of 783 pneumococcal strains isolated in Brazil between 1990 and 2014 to assess the evolution of penicillin non-susceptibility among pneumococci associated with asymptomatic carriage and invasive pneumococcal disease (IPD). The most common serotypes among carriage isolates were 19F, 6B, 6C, 23F, and 14. Among IPD isolates, the most frequent types were 14, 3, 6B, 5, 19F, and 4. We detected 21 types exclusively associated with IPD isolates, whereas non-typeable (NT) isolates were only detected in carriage. Nearly half of the isolates belonged to PCV10 serotypes, which remarkably decreased in occurrence (by nearly 50%) after PCV10 introduction (2011-2014), while non-PCV10 serotypes increased. PNSP frequency and levels were much higher among carriage isolates, but PNSP belonging to PCV10 serotypes were more common in IPD. While the occurrence of PNSP has decreased significantly among IPD isolates since 2011, it kept increasing among carriage strains. Such a difference can be attributed to the serotypes that emerged in each clinical source after PCV10 usage. PNSP with multidrug resistance profiles that emerged within carriage isolates comprised mostly serotypes 6C and 35B, as well as NT isolates. In turn, penicillin-susceptible capsular types 3, 20, and 8 have risen among IPD. Overall, our results reinforce the relevance of PNSP surveillance over a long period of time to better understand the dynamics of antimicrobial resistance in response to PCV introduction and may also contribute to improve control measures toward drug-resistant pneumococci.

15.
J Infect Dev Ctries ; 12(2): 127-136, 2018 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-31825915

RESUMEN

INTRODUCTION: Bacterial vaginosis (BV) is characterized by the depletion of Lactobacillus spp. population and increase of other species, especially Gardnerella vaginalis and Atopobium vaginae. This study aimed to investigate the vaginal microbiota structure of Brazilian women with and without BV according to Nugent Score and to assess the correlation among Nugent score and the quantification of BV-associated bacteria. METHODOLOGY: Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) assay was employed to characterize the vaginal microbiota structure. Quantification of Lactobacillus spp., G. vaginalis, A. vaginae, Mobiluncus sp. and M. hominis were determined by quantitative real-time PCR (qPCR). RESULTS: Clustering by PCR-DGGE revealed differences in microbial structure of the different patient groups. Gardnerella vaginalis, A. vaginae, M. hominis and Mobiluncus sp. were detected at high loads in BV-associated microbiota. Quantification of Lactobacillus spp. showed an inverse correlation with Nugent score while the loads of G. vaginalis, A. vaginae, M. hominis and Mobiluncus sp. indicated a direct correlation with this method. CONCLUSIONS: Despite Nugent score is considered the gold standard for BV diagnosis, qPCR stands out as a useful tool for bacteria quantification and an alternative for BV diagnosis. Vaginal microbiota is a complex microbial community although there is a common core among BV and non-BV women. Investigation of vaginal microbiota structure may contribute to the development of tools for diagnosis improvement and therapeutic regimen optimization.

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