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Escherichia coli is a leading cause of invasive bacterial infections in humans. Capsule polysaccharide has an important role in bacterial pathogenesis, and the K1 capsule has been firmly established as one of the most potent capsule types in E. coli through its association with severe infections. However, little is known about its distribution, evolution and functions across the E. coli phylogeny, which is fundamental to elucidating its role in the expansion of successful lineages. Using systematic surveys of invasive E. coli isolates, we show that the K1-cps locus is present in a quarter of bloodstream infection isolates and has emerged in at least four different extraintestinal pathogenic E. coli (ExPEC) phylogroups independently in the last 500 years. Phenotypic assessment demonstrates that K1 capsule synthesis enhances E. coli survival in human serum independent of genetic background, and that therapeutic targeting of the K1 capsule re-sensitizes E. coli from distinct genetic backgrounds to human serum. Our study highlights that assessing the evolutionary and functional properties of bacterial virulence factors at population levels is important to better monitor and predict the emergence of virulent clones, and to also inform therapies and preventive medicine to effectively control bacterial infections whilst significantly lowering antibiotic usage.

p. 1-10 Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2013-07-08T13:05:43Z No. of bitstreams: 1 444444444444.pdf: 281795 bytes, checksum: 594f3384ea132f663567fb63c1ab1d4e (MD5) Approved for entry into archive by Rodrigo Meirelles (rodrigomei@ufba.br) on 2013-10-31T17:43:19Z (GMT) No. of bitstreams: 1 444444444444.pdf: 281795 bytes, checksum: 594f3384ea132f663567fb63c1ab1d4e (MD5) Made available in DSpace on 2013-10-31T17:43:19Z (GMT). No. of bitstreams: 1 444444444444.pdf: 281795 bytes, checksum: 594f3384ea132f663567fb63c1ab1d4e (MD5) Previous issue date: 2013 Background: Although cerebrospinal fluid (CSF) culture is the diagnostic reference standard for bacterial meningitis, its sensitivity is limited, particularly when antibiotics were previously administered. CSF Gram staining and real-time PCR are theoretically less affected by antibiotics; however, it is difficult to evaluate these tests with an imperfect reference standard. Methods and findings: CSF from patients with suspected meningitis from Salvador, Brazil were tested with culture, Gram stain, and real-time PCR using S. pneumoniae, N. meningitidis, and H. influenzae specific primers and probes. An antibiotic detection disk bioassay was used to test for the presence of antibiotic activity in CSF. The diagnostic accuracy of tests were evaluated using multiple methods, including direct evaluation of Gram stain and real-time PCR against CSF culture, evaluation of real-time PCR against a composite reference standard, and latent class analysis modeling to evaluate all three tests simultaneously. Results: Among 451 CSF specimens, 80 (17.7%) had culture isolation of one of the three pathogens (40 S. pneumoniae, 36 N. meningitidis, and 4 H. influenzae), and 113 (25.1%) were real-time PCR positive (51 S. pneumoniae, 57 N. meningitidis, and 5 H. influenzae). Compared to culture, real-time PCR sensitivity and specificity were 95.0% and 90.0%, respectively. In a latent class analysis model, the sensitivity and specificity estimates were: culture, 81.3% and 99.7%; Gram stain, 98.2% and 98.7%; and real-time PCR, 95.7% and 94.3%, respectively. Gram stain and real-time PCR sensitivity did not change significantly when there was antibiotic activity in the CSF. Conclusion: Real-time PCR and Gram stain were highly accurate in diagnosing meningitis caused by S. pneumoniae, N. meningitidis, and H. influenzae, though there were few cases of H. influenzae. Furthermore, real-time PCR and Gram staining were less affected by antibiotic presence and might be useful when antibiotics were previously administered. Gram staining, which is inexpensive and commonly available, should be encouraged in all clinical settings. Salvador

Texto completo: acesso restrito. p. 5541–5546 Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2014-07-28T12:07:59Z No. of bitstreams: 1 Mitermayer G. Reis.pdf: 453887 bytes, checksum: d2029e78ca1d6ad83af9119a011a1221 (MD5) Approved for entry into archive by Delba Rosa (delba@ufba.br) on 2014-08-01T12:59:28Z (GMT) No. of bitstreams: 1 Mitermayer G. Reis.pdf: 453887 bytes, checksum: d2029e78ca1d6ad83af9119a011a1221 (MD5) Made available in DSpace on 2014-08-01T12:59:28Z (GMT). No. of bitstreams: 1 Mitermayer G. Reis.pdf: 453887 bytes, checksum: d2029e78ca1d6ad83af9119a011a1221 (MD5) Previous issue date: 2012 To combat rising incidence of serogroup C meningococcal disease in the city of Salvador, Brazil, the Bahia state immunization program initiated routine childhood immunization with meningococcal C conjugate vaccine (MenC) in February 2010, followed by mass MenC vaccination of city residents 10–24 years of age from May through August 2010. We analyzed trends in incidence of reported cases of meningococcal disease and serogroup distribution among meningococcal isolates identified in hospital-based surveillance in Salvador from January 2000 to December 2011 and estimated vaccine effectiveness using the screening method. Annual incidence of serogroup C meningococcal disease increased from 0.1 cases per 100,000 population during 2000–2006 to 2.3 in 2009 and 4.1 in 2010, before falling to 2.0 per 100,000 in 2011. Estimated coverage of mass vaccination reached 80%, 67% and 41% among 10–14, 15–19 and 20–24 year olds, respectively. Incidence in 2011 was significantly lower than average rates in 2008–2009 among children

texto completo: acesso restrito. p. 1139–1144 Submitted by Ana Valéria de Jesus Moura (anavaleria_131@hotmail.com) on 2012-03-24T14:16:58Z No. of bitstreams: 1 Serotype distribution and antimicrobial resistance of Streptococcus pneumoniae prior to introduction of the 10-valent pneumococcal conjugate vaccine in Brazil, 2000-2007.pdf: 136037 bytes, checksum: 68135737b9456e4c4b9bfd112c4737e8 (MD5) Made available in DSpace on 2012-03-24T14:16:58Z (GMT). No. of bitstreams: 1 Serotype distribution and antimicrobial resistance of Streptococcus pneumoniae prior to introduction of the 10-valent pneumococcal conjugate vaccine in Brazil, 2000-2007.pdf: 136037 bytes, checksum: 68135737b9456e4c4b9bfd112c4737e8 (MD5) Previous issue date: 2011 This study describes the serotype distribution and antibiotic resistance patterns among 397 S. pneumoniae meningitis case isolates recovered in Salvador, Brazil, during the period of 2000–2007, before introduction of the 10valent pneumococcal conjugate vaccine. The active hospitalbased surveillance showed a decline in the annual incidence rates of pneumococcal meningitis during the period of study, from 1.12 cases to 0.83 cases/100,000 persons for all age groups (P < 0.001), with an overall casefatality rate of 28.6% (113 of 395) for all patients and 41.9% (57 of 136) for those

This study describes the serotype distribution and antibiotic resistance patterns among 397 S. pneumoniae meningitis case isolates recovered in Salvador, Brazil, during the period of 2000-2007, before introduction of the 10-valent pneumococcal conjugate vaccine. The active hospital-based surveillance showed a decline in the annual incidence rates of pneumococcal meningitis during the period of study, from 1.12 cases to 0.83 cases/100,000 persons for all age groups (P0.001), with an overall case-fatality rate of 28.6% (113 of 395) for all patients and 41.9% (57 of 136) for those5 years of age. Serotypes 14 (n=55; 13.9%), 3 (n=32; 8.1%), 23F (n=32; 8.1%), 19F (n=31; 7.8%), 6B (n=30; 7.6%), 18C (n=28; 7.1%), and 6A (n=20; 5%) were the most prevalent serotypes. In patients5 years the estimated projected coverage of 7-, 10- and 13-valent conjugate vaccines was 74.3%, 75.7% and 83.1%, respectively. Antimicrobial susceptibility testing revealed that 22.1% (n=88) of isolates were non-susceptible to penicillin, 56% were non-susceptible to trimethoprim/sulphamethoxazole, and 29.6% were non-susceptible to tetracycline. Nonsusceptibility to penicillin and cefotaxime was detected solely among serotype 14 isolates (n=4; 1%). This study provides an important baseline to assess the impact of conjugate vaccine implantation on the epidemiology of meningitis due to Streptococcus pneumoniae in Salvador, Brazil.

Texto completo: acesso restrito. p.1577-1584 Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-07-04T12:33:27Z No. of bitstreams: 1 J Infect Dis.-2010-Lima-1577-84.pdf: 1684946 bytes, checksum: f362da267d0e82836f5169d057750652 (MD5) Made available in DSpace on 2013-07-04T12:33:27Z (GMT). No. of bitstreams: 1 J Infect Dis.-2010-Lima-1577-84.pdf: 1684946 bytes, checksum: f362da267d0e82836f5169d057750652 (MD5) Previous issue date: 2010 Since the introduction of Haemophilus influenzae type b (Hib) conjugate vaccines, meningitis caused by serotypes other than Hib has gained in importance. We conducted active hospital-based surveillance for meningitis over an 11-year period in Salvador, Brazil. H. influenzae isolates were serotyped and analyzed by polymerase chain reaction, pulsed-field gel electrophoresis, and DNA sequencing to identify strains with a specific deletion (IS1016) in the bexA gene (IS1016-bexA). We identified 43 meningitis cases caused by non-type b H. influenzae: 28 (65%) were caused by type a (Hia), 9 (21%) were caused by noncapsulated strains, and 3 (7%) each were caused by types e and f. Hia isolates clustered in 2 clonal groups; clonal group A strains (n = 9) had the IS1016-bexA deletion. Among children

Trabalho completo: acesso restrito, p. 112–115 Submitted by Bruna Lessa (lessbruna@gmail.com) on 2012-06-29T17:16:40Z No. of bitstreams: 1 (90)1-s2.0-S0732889309002545-main.pdf: 539277 bytes, checksum: 0cdc4a0705429506efcaba7596631d66 (MD5) Made available in DSpace on 2012-06-29T17:16:40Z (GMT). No. of bitstreams: 1 (90)1-s2.0-S0732889309002545-main.pdf: 539277 bytes, checksum: 0cdc4a0705429506efcaba7596631d66 (MD5) Previous issue date: 2009-10 The newly described Streptococcus pneumoniae serotype 6C accounted for 2.3% (16/709) of meningitis cases and 3.2% (3/95) of nasopharyngeal isolates from healthy individuals in Brazil. The strains were multidrug resistant (18.8%) and genetically diverse. Despite low serotype 6C prevalence, continuous surveillance is necessary to guide vaccine strategies.

Submitted by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2013-11-29T14:32:37Z No. of bitstreams: 1 Guilherme Ribeiro. Haemophilus influenzae meningitis 5 years after...2007.pdf: 294265 bytes, checksum: 57a6f80efeca525be8477bdad266899a (MD5) Made available in DSpace on 2013-11-29T14:32:37Z (GMT). No. of bitstreams: 1 Guilherme Ribeiro. Haemophilus influenzae meningitis 5 years after...2007.pdf: 294265 bytes, checksum: 57a6f80efeca525be8477bdad266899a (MD5) Previous issue date: 2007 The long-term impact of Haemophilus influenzae type b (Hib) conjugate vaccine, introduced throughout Latin America in the late 1990s, has not been evaluated. Active surveillance for H. influenzae meningitis was performed from August 9, 1996 to August 8, 2004 in Metropolitan Salvador, Brazil. Five years after the introduction of Hib conjugate vaccine, Hib meningitis incidence decreased from 2.39 to 0.06 cases per 100,000 population (98%) overall, and from 60.9 to 3.1 cases per 100,000 population (95%) in children

Submitted by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2013-11-29T13:08:17Z No. of bitstreams: 1 Guilherme Ribeiro.Prevention of Haemophilus influenzae type b...2003.pdf: 311135 bytes, checksum: fcf6123885c1260b5a15626a81a67538 (MD5) Made available in DSpace on 2013-11-29T13:08:17Z (GMT). No. of bitstreams: 1 Guilherme Ribeiro.Prevention of Haemophilus influenzae type b...2003.pdf: 311135 bytes, checksum: fcf6123885c1260b5a15626a81a67538 (MD5) Previous issue date: 2003-01 Surveillance for Haemophilus influenzae meningitis cases was performed in Salvador, Brazil, before and after introduction of H. influenzae type b (Hib) immunization. The incidence of Hib meningitis decreased 69% during the 1-year period after initiation of Hib immunization (from 2.62 to 0.81 cases/100,000 person-years; P