Streptococcus pneumoniae is a major cause of invasive diseases worldwide. It spreads through an interindividual transmission, followed by usually harmless colonization of the host. Possible transmission differences reflecting intrinsic strain features (e.g., serotype and antibiotic susceptibility) have been little studied so far. In this study, we used epidemiological data from an interventional trial of S. pneumoniae carriage among kindergartners and developed a mathematical model to estimate the transmission parameters of the different strains isolated during that study. We found small but significant transmissibility differences between the observed serotypes: serotypes 3, 6A, and 19A were found to be the most epidemic, while serotypes 23F, 9V, and 14 were the least epidemic. Further analysis indicated that, within a serotype, susceptible and resistant strains had different abilities to be transmitted. Susceptible-to-resistant transmission rate ratios were computed for five serotypes; susceptible strains were significantly more epidemic than resistant strains for serotypes 6A (mean, 1.02) and 19F (1.05). Serotype 19A resistant strains were not outcompeted by susceptible strains (0.97). Nonsignificant trends were observed for serotypes 6B (1.01) and 15A (0.98). Our results support the existence of heterogeneous abilities of the different serotypes for host-to-host transmission. They also suggest that antibiotic susceptibility within a serotype affects this transmissibility. We conclude that pneumococcal strains should not be considered equally at-risk in terms of transmission. Further quantification of strain-specific epidemic potential is needed, especially in a context of extensive use of conjugate vaccines with the aim of preventing pneumococcal infections.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3195016 | PMC |
| http://dx.doi.org/10.1128/AAC.00249-11 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Oral Regimens for Rifampin-Resistant, Fluoroquinolone-Susceptible Tuberculosis.
N Engl J Med
January 2025
From Médecins Sans Frontières (L.G., F.V.), Sorbonne Université, INSERM Unité 1135, Centre d'Immunologie et des Maladies Infectieuses (L.G.), Assistance Publique-Hôpitaux de Paris, Groupe Hospitalier Universitaire Sorbonne Université, Hôpital Pitié-Salpêtrière, Centre National de Référence des Mycobactéries et de la Résistance des Mycobactéries aux Antituberculeux (L.G.), and Epicentre (M.G., E. Baudin), Paris, and Translational Research on HIV and Endemic and Emerging Infectious Diseases, Montpellier Université de Montpellier, Montpellier, Institut de Recherche pour le Développement, Montpellier, INSERM, Montpellier (M.B.) - all in France; Interactive Development and Research, Singapore (U.K.); McGill University, Epidemiology, Biostatistics, and Occupational Health, Montreal (U.K.); UCSF Center for Tuberculosis (G.E.V., P.N., P.P.J.P.) and the Division of HIV, Infectious Diseases, and Global Medicine (G.E.V.), University of California at San Francisco, San Francisco; the National Scientific Center of Phthisiopulmonology (A.A., E. Berikova) and the Center of Phthisiopulmonology of Almaty Health Department (A.K.), Almaty, and the City Center of Phthisiopulmonology, Astana (Z.D.) - all in Kazakhstan; Médecins Sans Frontières (C.B., I.M.), the Medical Research Council Clinical Trials Unit at University College London (I.M.), and St. George's University of London Institute for Infection and Immunity (S.W.) - all in London; MedStar Health Research Institute, Washington, DC (M.C.); Médecins Sans Frontières, Mumbai (V. Chavan), the Indian Council of Medical Research Headquarters-New Delhi, New Delhi (S. Panda), and the Indian Council of Medical Research-National AIDS Research Institute, Pune (S. Patil) - all in India; the Centre for Infectious Disease Epidemiology and Research (V. Cox) and the Department of Medicine (H. McIlleron), University of Cape Town, and the Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease and Molecular Medicine (S.W.) - both in Cape Town, South Africa; the Institute of Tropical Medicine, Antwerp, Belgium (B. C. J.); Médecins Sans Frontières, Geneva (G.F., N.L.); Médecins Sans Frontières, Yerevan, Armenia (O.K.); the National Center for Tuberculosis and Lung Diseases, Tbilisi, Georgia (N.K.); Partners In Health (M.K.) and Jhpiego Lesotho (L.O.) - both in Maseru; Socios En Salud Sucursal Peru (L.L., S.M.-T., J.R., E.S.-G., D.E.V.-V.), Hospital Nacional Sergio E. Bernales, Centro de Investigacion en Enfermedades Neumologicas (E.S.-G.), Hospital Nacional Dos de Mayo (E.T.), Universidad Nacional Mayor de San Marcos (E.T.), and Hospital Nacional Hipólito Unanue (D.E.V.-V.) - all in Lima; Global Health and Social Medicine, Harvard Medical School (L.L., K.J.S., M.L.R., C.D.M.), Partners In Health (L.L., K.J.S., M.L.R., C.D.M.), the Division of Global Health Equity, Brigham and Women's Hospital (K.J.S., M.L.R., C.D.M.), the Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, (L.T.), and Harvard T.H. Chan School of Public Health (L.T.) - all in Boston; and the Indus Hospital and Health Network, Karachi, Pakistan (H. Mushtaque, N.S.).
Background: For decades, poor treatment options and low-quality evidence plagued care for patients with rifampin-resistant tuberculosis. The advent of new drugs to treat tuberculosis and enhanced funding now permit randomized, controlled trials of shortened-duration, all-oral treatments for rifampin-resistant tuberculosis.
Methods: We conducted a phase 3, multinational, open-label, randomized, controlled noninferiority trial to compare standard therapy for treatment of fluoroquinolone-susceptible, rifampin-resistant tuberculosis with five 9-month oral regimens that included various combinations of bedaquiline (B), delamanid (D), linezolid (L), levofloxacin (Lfx) or moxifloxacin (M), clofazimine (C), and pyrazinamide (Z).
Detection and characterization of pathogenic Bacillus haynesii from Tribulus terrestris extract: ways to reduce its levels.
Braz J Microbiol
January 2025
Innovation and Drug Discovery, Sava Healthcare Limited, Research Center, MIDC, Block D1, Plot No. 17/6, Chinchwad, Pune, 411019, India.
Plant parts such as roots, bark, leaves, flowers, and fruits that hold ethnopharmacological significance are naturally prone to microbial contamination, influenced by environmental factors like moisture and humidity. This study focuses on assessing the microbial load in the raw material of Tribulus terrestris (TT). The primary bacterium isolated from the pulverized raw material was identified as Bacillus haynesii through 16S rRNA sequencing.
View Article and Find Full Text PDF[Investigation of the Antifungal Susceptibility and Virulence Factors of Fusarium Strains Isolated from Clinical Samples].
Mikrobiyol Bul
January 2025
Aydın Adnan Menderes Üniversitesi Tıp Fakültesi, Tıbbi Mikrobiyoloji Anabilim Dalı, Aydın.
Fusarium türleri, insanlarda keratit ve onikomikoz başta olmak üzere invaziv veya invaziv olmayan çeşitli enfeksiyonlarda etken olan küf mantarlarıdır. Taksonomide Fusarium cinsi, tür kompleks [species complex (SC)]'lere ayrılmış, SC'ler de türlere ayrılmıştır. SC/tür düzeyinde identifikasyonun, morfolojik özelliklere göre yapılmasının güçlüğü nedeniyle moleküler yöntemlerin kullanımı önerilmektedir.
View Article and Find Full Text PDFA case of bacteremia in a 38-year-old homeless male originating from a maggot-infested amputated foot.
IDCases
January 2025
University of Kansas Medical Center, Department of Internal Medicine, Division of Infectious Diseases, 3901 Rainbow Blvd., Mailstop 1028, Kansas City, KS 66160, USA.
() was first isolated from the larval stage of the fly vector It is a gram-negative, non-motile, strictly aerobic rod that thrives in temperatures between 28º C and 37º C. Its strong chitinase activity aids in metamorphosis, which suggests a symbiotic relationship with the fly. Although rare, has been implicated in human infections, like bacteremia and osteomyelitis, typically transmitted through fly larvae in skin wounds.
View Article and Find Full Text PDFCeftazidime-resistance in pediatric melioidosis: A case report and literature review.
IDCases
January 2025
Institute of Health and Community Medicine, Universiti Malaysia Sarawak, Sarawak, Malaysia.
We report a first case of ceftazidime-resistant pediatric melioidosis involving a previously healthy seven-year-old boy who presented with right lobar pneumonia complicated with a 5-cm lung abscess. Ceftazidime was initiated on Day-6 of admission when (ceftazidime-susceptible, minimum inhibitory concentration [MIC] 1.0 mcg/mL) was isolated from blood.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!