Methicillin-resistant Staphylococcus aureus isolated from an intensive care unit in Minas Gerais, Brazil, over a six-year period

ABSTRACT To characterize methicillin-resistant Staphylococcus aureus isolates from an intensive care unit of a tertiary-care teaching hospital, between 2005 and 2010. A total of 45 isolates were recovered from patients admitted to the intensive care unit in the study period. Resistance rates higher than 80% were found for clindamycin (100%), erythromycin (100%), levofloxacin (100%), azithromycin (97.7%), rifampin (88.8%), and gentamycin (86.6%). The SCCmec typing revealed that the isolates harbored the types III (66.7%), II (17.8%), IV (4.4%), and I (2.2%). Four (8.9%) isolates carried non-typeable cassettes. Most (66.7%) of the isolates were related to the Brazilian endemic clone from CC8/SCCmec III, which was prevalent (89.3%) between 2005 and 2007, while the USA100/CC5/SCCmec II lineage emerged in 2007 and was more frequent in the last few years. The study showed high rates of antimicrobial resistance among methicillin-resistant S. aureus isolates and the replacement of Brazilian clone, a well-established hospital lineage, by the USA100 in the late 2000s, at the intensive care unit under study.

Comparative metagenome of a stream impacted by the urbanization phenomenon

Abstract Rivers and streams are important reservoirs of freshwater for human consumption. These ecosystems are threatened by increasing urbanization, because raw sewage discharged into them alters their nutrient content and may affect the composition of their microbial community. In the present study, we investigate the taxonomic and functional profile of the microbial community in an urban lotic environment. Samples of running water were collected at two points in the São Pedro stream: an upstream preserved and non-urbanized area, and a polluted urbanized area with discharged sewage. The metagenomic DNA was sequenced by pyrosequencing. Differences were observed in the community composition at the two sites. The non-urbanized area was overrepresented by genera of ubiquitous microbes that act in the maintenance of environments. In contrast, the urbanized metagenome was rich in genera pathogenic to humans. The functional profile indicated that the microbes act on the metabolism of methane, nitrogen and sulfur, especially in the urbanized area. It was also found that virulence/defense (antibiotic resistance and metal resistance) and stress response-related genes were disseminated in the urbanized environment. The structure of the microbial community was altered by uncontrolled anthropic interference, highlighting the selective pressure imposed by high loads of urban sewage discharged into freshwater environments.

O papel da microbiota na modulação da homeostase dos hospedeiros: correlação entre micobioma intestinal e obesidade / The role of microbiota in the modulation hosts homeostasis: correlation between obesity and intestinal mycobiome

Os fungos apresentam papel importante na saúde humana, sendo componentes da microbiota humana de diversos sítios anatômicos como, por exemplo, pele, cavidade bucal, trato gastrintestinal e trato geniturinário. São também agentes etiológicos de várias infecções, desde micoses superficiais até sistêmicas. Os fungos participam na regulação do sistema imunológico, podendo promover o surgimento de alergias das vias aéreas superiores. Estão presentes na composição da microbiota intestinal, formando o micobioma. Portanto, seu papel no desenvolvimento da obesidade deve ser considerado, atuando tanto na modulação da resposta imune local quanto através de sua interação com os demais microrganismos da microbiota intestinal. Este trabalho tem como objetivo revisar aspectos da participação microbiana na etiopatogenia da obesidade e discutir a participação dos fungos no microbioma intestinal, sua relação com a obesidade e as perspectivas futuras, com a utilização de metodologias moleculares, para um melhor entendimento do papel dos fungos na microbiota intestinal na saúde e na doença.

Associação entre cultura de secreção vaginal, características sociodemográficas e manifestações clínicas de pacientes com diagnóstico de candidíase vulvovaginal / Association between vaginal secretion culture, socio-demographic characteristics and clinical manifestations of patients with vulvovaginal candidiasis

OBJETIVO: Investigar a etiologia, o perfil epidemiológico de pacientes com candidíase vulvovaginal (CVV) e possíveis fatores predisponentes. MÉTODOS: Secreção vaginal das pacientes foi semeada em ágar Sabouraud e amostras de leveduras foram isoladas e identificadas por Polymerase Chain Reaction (PCR). Dados demográficos, clínicos e fatores predisponentes foram obtidos por meio de questionário. Para análise estatística, foram utilizados os testes t de Student, Fischer e do χ², com auxílio do software Statistical Package for the Social Sciences (SPSS), com nível de significância de 5%. RESULTADOS: Foram avaliadas 69 pacientes, com idade entre 15 e 52 anos, predominando mulheres brancas (79,7%), com escolaridade de nível superior completo (58%), casadas (56,5%) e com vida sexual ativa (97,1%). Dentre elas, 34,8% eram gestantes, 7,2% diabéticas, 1,4% soropositivas para AIDS e 36,2% usavam anticoncepcional oral. Antibioticoterapia recente foi citada por 13% das pacientes, uso de antifúngico por 5,8% e de antitricomonas por 1,4%. Uso de corticosteroides foi relatado por 2,9% das participantes e de antineoplásicos, por 1,4%. Fluxo vaginal e prurido foram as principais queixas apresentadas, respectivamente, por 97,1 e 73,9% das pacientes, seguido de ardência (63,8%) e hiperemia (63,8%). Quando presente, o fluxo foi majoritariamente branco (88,1%) ou grumoso (86,6%). O diagnóstico foi confirmado pela cultura em 55 (79,7%) pacientes, sendo 4 casos de infecção mista. A espécie prevalente foi C. albicans, seguida por um caso de C. glabrata, que foi encontrada em mais duas pacientes em associação com C. albicans. Nas outras duas infecções polimicrobianas, C. lusitaniae foi isolada com C. albicans. CONCLUSÕES: Embora a positividade da cultura tenha sido alta e os dados clínicos de CVV sejam característicos, a sintomatologia não é patognomônica. C. albicans é a espécie prevalente, mas deve-se atentar para a ocorrência de outras espécies na etiologia de CVV, como a emergência de C. lusitaniae.

PURPOSE: To investigate the etiology and the epidemiological profile of patients with vulvovaginal candidiasis (VVC) and predisposing factors. METHODS: Vaginal secretions were streaked in Sabouraud agar and yeast samples were isolated and identified by Polymerase Chain Reaction (PCR). Demographic and clinical data were obtained with a questionnaire. For statistical analysis, the Student's t-test, the χ² and Fischer tests were applied as needed using the Statistical Package for Social Sciences (SPSS) software, with the level of significance set at 5%. RESULTS: Sixty-nine patients aged from 15 to 52 years were evaluated. They were predominantly white (79.7%), with higher education (58%), married (56.5%) and sexually active (97.1%). Among them, 34.8% were pregnant, 7.2% diabetic, 1.4% seropositive for AIDS, and 36.2% were using oral contraceptives. Recent antibiotic therapy was mentioned by 13% of the patients, and antifungal or anti-trichomonas therapy was mentioned by 5.8 and 1.4% of the patients, respectively. Corticosteroid use was reported by 2.9% and antineoplastic by 1.4%. Vaginal discharge and itching were the main complaints (97.1 and 73.9%), followed by burning (63.8%) and erythema (63.8%). When present, the vaginal flow was predominantly white (88.1%) or lumpy (86.6%). The diagnosis was confirmed by culture in 55 (79.7%) patients, with mixed infections in 4 patients. The most prevalent species was C. albicans, followed by C. glabrata (one monoinfection and two mixed infections with C. albicans). C. lusitaniae and C. albicans were also identified in mixed infections (two patients). CONCLUSION: Despite the high culture positivity and clinical data characteristic of VVC, the symptoms were not pathognomonic. C. albicans is the most prevalent species, but other species are also involved in VVC etiology, such as the emergence of C. lusitaniae.

Detection and enumeration of periodontopathogenic bacteria in subgingival biofilm of pregnant women

The aim of this study was to use the fluorescence in situ hybridization (FISH) technique to test the hypothesis of qualitative and quantitative differences of 8 periodontopathogens between pregnant and non-pregnant women. This cross-sectional study included 20 pregnant women in their second trimester of pregnancy and 20 non-pregnant women. Probing depth, bleeding on probing, clinical attachment level, and presence of calculus were recorded. Subgingival plaque samples were collected and the FISH technique identified the presence and numbers of Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Campylobacter rectus, Porphyromonas gingivalis, Treponema denticola, Fusobacterium nucleatum, Prevotella intermedia and Prevotella nigrescens. The Mann-Whitney U-test was applied to compare the data between the two groups. The mean age, ethnicity, marital status, education, and economic level in both groups were similar. The clinical parameters showed no significant differences between pregnant and non-pregnant women. The numbers of subgingival periodontopathogens were not found to be significantly different between groups, despite the higher mean counts of P. intermedia in pregnant women. Colonization patterns of the different bacteria most commonly associated with periodontal disease were not different in the subgingival plaque of pregnant and non-pregnant women.

Os microorganismos contaminam as escovas dentais? / Do microorganisms contaminate the toothbrushes?

Esta é uma revisão de literatura que teve como objetivo estudar se a escova dental é um reservatório de microrganismos causadores de doenças. Foi possível concluir que as escovas dentais podem apresentar contaminação por microorganismos da boca e do ambiente. Nessas condições podem ser capazes de permitir a infecção cruzada e a auto-infecção. Dada a importância deste fato os cuidados de desinfecção das escovas dentais devem ser adotados.

This review aimed to study the toothbrush as a reservatory of pathogenic microorganisms. to . We concluded that toothbrushes can contain microorganisms of the mouth and the environment. Under these conditions it may be able to allow cross-infections and auto-infection. So, toothbrushes disinfection is essential to avoid the emergence of oral infections

Detection of Group B Streptococcus in Brazilian pregnant women and antimicrobial susceptibility patterns

Group B Streptococcus (GBS) is still not routinely screened during pregnancy in Brazil, being prophylaxis and empirical treatment based on identification of risk groups. This study aimed to investigate GBS prevalence in Brazilian pregnant women by culture or polymerase chain reaction (PCR) associated to the enrichment culture, and to determine the antimicrobial susceptibility patterns of isolated bacteria, so as to support public health policies and empirical prophylaxis. After an epidemiological survey, vaginal and anorectal specimens were collected from 221 consenting laboring women. Each sample was submitted to enrichment culture and sheep blood agar was used to isolate suggestive GBS. Alternatively, specific PCR was performed from enrichment cultures. Antimicrobial susceptibility patterns were determined for isolated bacteria by agar diffusion method. No risk groups were identified. Considering the culture-based methodology, GBS was detected in 9.5 percent of the donors. Twenty five bacterial strains were isolated and identified. Through the culture-PCR methodology, GBS was detected in 32.6 percent specimens. Bacterial resistance was not detected against ampicillin, cephazolin, vancomycin and ciprofloxacin, whereas 22.7 percent were resistant to erythromycin and 50 percent were resistant to clindamycin. GBS detection may be improved by the association of PCR and enrichment culture. Considering that colony selection in agar plates may be laboring and technician-dependent, it may not reflect the real prevalence of streptococci. As in Brazil prevention strategies to reduce the GBS associated diseases have not been adopted, prospective studies are needed to anchor public health policies especially considering the regional GBS antimicrobial susceptibility patterns.

Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of Bacteroides fragilis group in diarrheic and non-diarrheic feces from Brazilian infants

Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG) are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110) and non-diarrheic (n=65) fecal samples from children aged 0-5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3 percent of the fecal samples (55 percent diarrheic and 80.4 percent non-diarrheic), and 4.6 percent were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol. The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children.

Bacterial vaginosis: clinical, epidemiologic and microbiological features / Bacterial vaginosis: clinical, epidemiologic and microbiological features

Bacterial Vaginosis (BV) is a polymicrobial clinical syndrome, whose etiology has not been fully understood. It occurs in approximately 30% of the women in childbearing age and is the result of the shift of protective resident microorganisms as Lactobacillus spp. by opportunistic pathogenic bacteria such as Gardnerella vaginalis. Patients with BV generally present copious, thin, homogeneous, milky, foul-smelling flow. Vaginal pH is > 4.5 and microscopy reveals bacteria-covered epithelial cells, termed “clue cells”. Around 50% of the patients are asymptomatic and the disease is associated with gynecologic complications, such as cervicitis, salpingitis, endometritis, post-operative infections and pelvic inflammatory disease; and obstetric complications, such as premature rupture of the membranes, preterm deliveries, chorioamniotitis and postpartum endometritis. Although the Nugent´s method is accepted as the “gold standard” for diagnosing BV, Amsel criteria are generally used for diagnosis in clinical practice. The Papanicolaou method is a valid diagnostic option, chiefly when it yields a positive result (mean specificity 95% when compared to gold standard). G. vaginalis has been almost universally recovered from women with BV, plays an important role in the pathogenesis of the disease, besides it may be detected in about 50% of healthy women. According to the literature, first-line drugs for BV treatment worldwide are metronidazole and clindamycin. However, regional studies on G. vaginalis drug susceptibility patterns are needed faced the so fast growing antimicrobial resistance phenomenon.

Avaliação da contaminação bacteriana em resinas compostas utilizadas nas clínicas de graduação da FO-UFJF / Evaluation of bacterial contamination in composite resins used at graduation clinics of FO-UFJF

Objetivo: avaliar a contaminação bacteriana em resinas compostas utilizadas nas clínicas de graduação da Faculdade de Odontologia da Universidade Federal de Juiz de Fora. Méodos: realizou-se a detecção de crescimento bacteriano em cultura de amostras de 50 tubos de resina composta, sendo 25 Charisma (Heraeus-kulzer) e 25 Durafill (Heraeus-kulzer). Dois tubos novos de cada marca comercial serviram como grupo controle e os demais utilizados no estudo encontravam-se em uso nas clínicas de graduação, formando o grupo teste. A coleta das amostras foi realizada com técnica asséotica em capela de fluxo laminar, com uso de palitos previamente esterilizados. Após a coleta do material e inóculo em meio de cultura, os sistemas de avaliação foram mantidos em estufa bacteriológica a 37ºC. Resultados: após 24 horas de incubação, observou-se a turvação do meio de cultura em apenas 2 tubos de ensaio do grupo teste. Os resultados foram submetidos ao teste Qui Quadrado de Pearson, não mostrando resultados estatisticamente significativos (p>0.005). Conclusão: as resinas compostas utilizadas na FO/UFJF não estavam contaminadas e acredita-se que as técnicas de manutenção da cadeia asséptica empregadas nas clínicas de graduação da instituição foram eficazes, mas podem não ser as únicas responsáveis pela não contaminação.

Obective: evaluate the bacterial contamination in composite resins used daily at graduation clinical of FO/UFJF. Methods: for detection of bacterial growth on culture of samples from 50 tubes of composite resin, and 25 Charisma ® (Heraeus-Kulzer) and 25 Durafill ® (Heraeus-Kulzer). Two new tubes of each brand served as the control group and the other tubes of composite resin used in the study were in use in clinical studies, forming the test group. The collection of samples was performed with aseptic technique in the chapel of laminar flow, using previously sterilized toothpicks. After collecting the material and inoculum in the culture medium, the evaluation systems were maintained in bacteriological incubator at 37º C. Results: after 24 hours of incubation, observed the turbidity of the culture medium in only 2 test tubes of test group. The results were submitted to Pearson's Chi Square, not showing statistically significant results (p>0.005). Conclusion: the composite resins used in the FO/UFJF were not contaminated and it is believed that the technical maintenance of the aseptic chain employed in clinical studies of the institution were effective, but may not be the only ones responsible for not contamination.

Clinical, microbiological and therapeutic aspects of vulvovaginal candidiasis and recurrent vulvovaginal candidiasis: importance of regionalsurveys

Vulvovaginal candidiasis (VVC) has a varied aetiology. The yeasts involved in this disease have presented increased resistance to the azoles and poliens, the drugs of choice for treatment. In recurrent VVC, the therapeutic difficulties are even greater. The epidemiological relevance of aetiological diagnosis and of the antifungigram in clinical treatment is discussed.

Ocorrência de bactérias clinicamente relevantes nos resíduos de serviços de saúde em um aterro sanitário brasileiro e perfil de susceptibilidade a antimicrobianos / Occurrence of clinically relevant bacteria in health service waste in a Brazilian sanitary landfill and antimicrobial susceptibility profile

Os resíduos de serviços de saúde suscitam polêmica quanto a importância para a saúde humana, animal e ambiental. Avaliou-se a ocorrência de bactérias clinicamente relevantes na pilha de resíduos de serviços de saúde em um aterro sanitário e seu perfil de susceptibilidade aos antimicrobianos. Alíquotas de chorume foram processadas para isolamento seletivo de Staphylococcus sp, bastonetes Gram negativos da família Enterobacteriaceae e não fermentadores. Resistência bacteriana a todos os antimicrobianos testados foi observada em todos os grupos microbianos, além de resistência a mais de uma droga. Os resultados permitem sugerir que bactérias viáveis nos resíduos de serviços de saúde representam riscos à saúde humana e animal. Além disso, a ocorrência de linhagens multirresistentes sustenta a hipótese dos resíduos de serviços de saúde atuarem como reservatórios de marcadores de resistência, com impacto ambiental. A falta de legislação regional de segregação, tratamento e destino de resíduos podem expor diferentes populações a riscos de transmissão de doenças infecciosas associadas a microrganismos multirresistentes.

Health service waste gives rise to controversy regarding its importance for human, animal and environmental health. Occurrences of clinically relevant bacteria in piles of health service waste in a sanitary landfill and their antimicrobial susceptibility profile were evaluated. Aliquots of leachate were processed for selective isolation of Staphylococcus sp, Gram-negative rods of the Enterobacteriaceae family and non-fermenters. Bacterial resistance to all the antimicrobials tested was observed in all microbial groups, including resistance to more than one drug. The results make it possible to suggest that viable bacteria in health service waste represent risks to human and animal health. Furthermore, occurrences of multiresistant strains support the hypothesis that health service waste acts as a reservoir for resistance markers, with an environmental impact. The lack of regional legislation concerning segregation, treatment and final disposal of waste may expose different populations to risks of transmission of infectious diseases associated with multiresistant microorganisms

Estudo piloto sobre a avaliação da periodontite crônica em pacientes com doença renal crônica / Pilot study on the association of chronic periodontitis in patients with chronic kidney disease

Introdução: Periodontite crônica (PC) é uma infecção bacteriana dos tecidos de suporte, encontrada na placa dental subgengival, e pode determinar uma resposta inflamatória sistêmica. Objetivo: Avaliar a ocorrência de PC em pacientes com doença renal crônica (DRC) pré-dialítica. Material e Métodos: O estagiamento da DRC baseou-se no Kidney Disease Outcome Quality Initiative da National Kidney Foundation. A filtração glomerular (FG) foi estimada pela equação da Modification of Diet in Renal Disease a partir da creatinina plasmática. A resposta inflamatória foi determinada pela proteína C-reativa (PCR) em 30 pacientes, divididos em três grupos: o grupo 1 (G1), composto de seis pacientes com PC e sem DRC, grupo 2 (G2), composto de 19 pacientes com PC localizada e DRC, e o grupo 3 (G3), composto de cinco pacientes com PC generalizada e DRC. A gravidade da PC baseou-se na profundidade de sondagem (PS). A identificação das bactérias foi realizada pela técnica de reação em cadeia da polimerase. Resultados: A PCR do G1 (2,4 ± 2,5 mg/L) não foi diferente do G2 (4,6 + 4,5 mg/L, p = 0,1), mas observou-se uma tendência de diferença relativamente ao G3 (7,6 ± 3,8 mg/L, p = 0,05). Comparativamente à PS do grupo G1 (PS = 2,1 ± 0,6 mm), as do G2 (PS = 2,9 ± 1,2 mm, p = 0,05) e do G3 (G3 de 4,3 ± 0,8 mm, p = 0,04) foram mais graves. Não foram observadas diferenças estatísticas entre as frequências das bactérias isoladas nos três grupos. Conclusão: Apesar do número limitado de pacientes, nossos resultados sugerem que a PC generalizada é mais frequente nos pacientes com DRC.

Introduction: Chronic periodontitis (CP) is a bacterial infection of the supporting soft tissue in the subgingival dental plaque that can trigger systemic inflammation. Objective: The objective of this study was to evaluate the incidence of CP in patients with predialytic and chronic kidney disease. Material and Methods: The definition of ESRD was based on the Kidney Disease Outcome Quality Initiative proposed by the National Kidney Foundation. The Modification of Diet in Renal Disease equation [P2] was used to estimate the glomerular filtration rate (GFR) from the plasma creatinine level. C-reactive protein (CRP) was used to determine the inflammatory response in 30 patients divided in three groups: group 1 (G1) was composed of six patients without CKD and with CP; group 2 (G2) comprised 19 patients with CKD and localized CP; and group 3 (G3) was composed of five patients with CKD and generalized CP. The severity of CP was based on the probing depth (PD). Bacteria were identified by polymerase chain reaction. Results: C-reactive protein in G1 (2.4 ± 2.5 mg/L) did not differ from that in G2 (4.6 ± 4.5 mg/L, p = 0.1), but a tendency to differ compared to G3 (7.6 ± 3.8 mg/L, p = 0.05) was observed. Probing depth in G1 (2.1 ± 0.6 mm) was less severe than in G2 (PD = 2.9 ± 1.2 mm, p = 0.05) and G3 (PD = 4.3 ± 0.8 mm, p = 0.04). Statistical differences in the frequency of the bacteria isolated in all three groups were not observed. Conclusion: Despite the limited number of patients, our results suggest that generalized CP is more frequent in patients with ESRD.

Doença perinatal associada aos estreptococos do Grupo B: aspectos clínico-microbiológicos e prevenção / Perinatal Group B streptococcal disease: clinical-microbiological aspects and prevention

Os cocos Gram-positivos Streptococcus agalactiae ou estreptococos do Grupo B de Lance (EGB) são bactérias que fazem parte da microbiota residente nas membranas mucosas de seres humanos, colonizando principalmente os tratos gastrintestinal e geniturinário. Sua importância é relacionada à contaminação vertical dos neonatos de parturientes colonizadas, que pode acontecer de forma ascendente ainda no útero ou durante o parto. Mundialmente, a prevalência da colonização pelos EGB nas gestantes varia de 3% a 41%. Entre as infecções neonatais associadas a estes microrganismos destacam-se, principalmente, a septicemia e a pneumonia e, em menor freqüência, meningite, celulite, osteomielite e artrite séptica. Em 1996, foi publicado o primeiro guia preventivo da doença estreptocócica perinatal, estabelecendo as diretrizes e critérios para a prevenção da transmissão vertical destes agentes. Em 2002, foi estabelecido o uso da profilaxia antimicrobiana intraparto e a investigação rotineira da colonização pelo S. agalactiae no final da gestação, através de cultura de material vaginal e retal em meio seletivo. Nos países que adotaram estas medidas profiláticas, registrou-se um decréscimo significativo na incidência da doença. No Brasil, a mortalidade neonatal é um grave problema de saúde pública e ainda não foram adotadas estratégias de prevenção e tratamento para reduzir a prevalência de infecção neonatal pelo EGB. Considerando o custo elevado e as graves conseqüências da doença estreptocócica perinatal, verifica-se a necessidade de elaboração de políticas de saúde, visando reduzir a transmissão vertical. Assim, percebe-se a necessidade de atualização literária, englobando aspectos microbiológicos e preventivos da doença estreptocócica perinatal, visando, sobretudo, a uma abordagem que facilite o entendimento e a aplicabilidade deste conhecimento dentro do cenário nacional.

Lance group B streptococci (GBS, or Streptococcus agalactiae) are Gram-positive bacterial components of the resident microbiota of human mucous membranes, mainly colonizing the gut and the urogenital tract. Vertical perinatal transmission of colonized women is known to occur as both, intrauterine infection or through contamination during labor. The worldwide prevalence of GBS-colonized pregnant women ranges from 3% to 41%. Neonatal infection may lead mainly to sepsis and pneumonia, with less frequent occurrences of meningitis, celullitis, osteomyelitis and septic arthritis. The first guidelines for prevention of the vertical transmission of perinatal streptococcal disease were issued in 1996. Routine investigation of the S. agalactiae colonization status, through selective medium culture of vaginal and rectal secretions at the term of pregnancy, and intrapartum antimicrobial prophylaxis, were established in 2002. A significant decrease in the incidence of perinatal infection was seen in the countries that adopted the prophylactic measures. Although neonatal mortality in Brazil is a serious public health issue, no preventive or treatment strategies targeting GBS-neonatal infection have been adopted. Due to the high costs and serious consequences of perinatal streptococcal disease, health policies aiming at reducing vertical transmission are clearly called for. In this regard, literary updates are needed, specially considering microbiology and prevention of GBS-neonatal infection, to give clearly understandable and applicable supportive arguments, in the national scenery.