É isso mesmo. Agora a tinta também pode ser usada como auxiliar nos tratamentos de saúde. Mas calma aí. Nada de querer fazer uso tópico. A nova tinta, continua restrita as superfícies, mas ao ser aplicada nas paredes e tetos dos hospitais, vira arma poderosa na luta contra as infecções hospitalares causadas por bactérias resistentes a antibióticos.

   Na verdade o uso do dióxido de titânio é comum em tintas brancas. Ao ser exposto a luz UV reage com as partículas de água da superfície atacando outras bactérias. Porém seu efeito bactericida é neutralizado pela presença de outros aditivos, como carbonato de cálcio, usados em tintas comuns.

   O estudo sugere que se for acrescentado mais dióxido de titânio e removidos alguns aditivos pode-se potencializar o efeito bactericida. No entanto encontrar o equilibrio ideal na composição das tintas ainda vai levar tempo e mais estudos precisam ser feitos.

   De qualquer modo é um grande avanço. É a resposta da ciência à crescente preocupação mundial com a disseminação das superbactérias.

   Diante da ineficiência dos atuais sistemas de esterilização a nova tinta é uma promessa eficiente e barata de combate a um inimigo letal e invisível que é uma grande ameaça não só para área da saúde como também para a indústria farmacêutica e alimentícia.  

Los neutrófilos son glóbulos blancos de tipo granulocito que miden entre 12 y 18 micras. Es una célula muy móvil y con consistencia gelatinosa le facilita atravesar las paredes de los vasos sanguíneos para migrar hacia los tejidos, ayudando en la destrucción de microbios y respondiendo a estímulos inflamatorios.

Lukas Fenner,1 Andreas F. Widmer,2 Clarisse Straub,1 and Reno Frei1*

Microbiology Laboratory,1 Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Petersgraben 4, CH-4031 Basel, Switzerland2

The number of positive anaerobic blood culture results per 1,000 blood cultures performed decreased from 12.6 in the period from 1997 to 2001 to 7.0 in the period from 2002 to 2006 (P < 0.001), as did the proportion of isolated anaerobic organisms compared to the number of all organisms isolated from blood cultures (7.6% to 4.3% [P < 0.001]), while positive aerobic cultures remained stable. In contrast, the proportion of Bacteroides fragilis group members and gram-positive cocci within the anaerobic group increased (26.8% to 36.7% [P = 0.004] and 5.4% to 12% [P < 0.001], respectively). The number of patients with anaerobic bacteremia decreased from 122 patients in 1997 to 69 in 2006.

abstract
http://jcm.asm.org/cgi/content/abstract/46/7/2432

Christine Moore, ART, Jastej Dhaliwal, MSc, Agnes Tong, MSc, Sarah Eden, BScN,
Cindi Wigston, BSc, and Barbara Willey, ART, for the Mount Sinai Hospital Infection Control Team; Allison McGeer, MSc, MD

From Mt. Sinai Hospital (C.M., A.T., S.E., C.W., B.W., A.M.), and the Department of Public Health Sciences, University of Toronto (J.D., A.M.), Toronto, Ontario, Canada. Other members of the Mount Sinai Hospital Infection Control Team are listed at the end of the text.

Objective.  To identify risk factors for acquisition of methicillin-resistant Staphylococcus aureus (MRSA) in patients exposed to an MRSA-colonized roommate.

Design.  Retrospective cohort study.

Setting.  A 472-bed acute-care teaching hospital in Toronto, Canada.

Patients.  Inpatients who shared a room between 1996 and 2004 with a patient who had unrecognized MRSA colonization.

Methods.  Exposed roommates were identified from infection-control logs and from results of screening for MRSA in the microbiology database. Completed follow-up was defined as completion of at least 2 sets of screening cultures (swab samples from the nares, the rectum, and skin lesions), with at least 1 set of samples obtained 7–10 days after the last exposure. Chart reviews were performed to compare those who did and did not become colonized with MRSA.

Results.  Of 326 roommates, 198 (61.7%) had completed follow-up, and 25 (12.6%) acquired MRSA by day 7–10 after exposure was recognized, all with strains indistinguishable by pulsed-field gel electrophoresis from those of their roommate. Two (2%) of 101 patients were not colonized at day 7–10 but, with subsequent testing, were identified as being colonized with the same strain as their roommate (one at day 16 and one at day 18 after exposure). A history of alcohol abuse (odds ratio [OR], 9.8 [95% confidence limits {CLs}, 1.8, 53]), exposure to a patient with nosocomially acquired MRSA (OR, 20 [95% CLs, 2.4, 171]), increasing care dependency (OR per activity of daily living, 1.7 [95% CLs, 1.1, 2.7]), and having received levofloxacin (OR, 3.6 [95% CLs, 1.1, 12]) were associated with MRSA acquisition.

Conclusions.  Roommates of patients with MRSA are at significant risk for becoming colonized. Further study is needed of the impact of hospital antimicrobial formulary decisions on the risk of acquisition of MRSA.

abstract
http://www.journals.uchicago.edu/doi/abs/10.1086/588567

Thean Yen Tan,1* Siew Yong Ng,1 and Jie He2

Division of Laboratory Medicine, Changi General Hospital, Singapore,1 Department of Pathology, Singapore General Hospital, Singapore2

This study validated abbreviated methods for the presumptive identification of Staphylococcus lugdunensis and studied the antibiotic susceptibilities of 106 isolates. The combination of positive responses to ornithine and pyrrolidonyl arylamidase identified all S. lugdunensis isolates. Resistance to penicillin and methicillin was detected in 27 and 5% of isolates, respectively. 
 
abstract
http://jcm.asm.org/cgi/content/abstract/46/7/2393

Una de las preguntas más frecuentes que se hacen los científicos cuando se plantean la posibilidad de encontrar vida en otros planetas es si algún organismo es capaz de vivir de forma independiente, sin necesidad de recibir la luz del sol o de alimentarse de otros seres vivos. La duda ha quedado siempre sin respuesta. El descubrimiento en una mina de oro, a casi tres kilómetros de profundidad, de una nueva bacteria ha conseguido abrir una nueva puerta en la investigación astrobiológica.

"Ahora que tenemos la prueba de la existencia de un organismo como este, es excitante, hasta en un sentido filosófico, saber que todo lo necesario para la vida está empaquetado dentro de un solo genoma", afirma Dylan Chivian, autor del descubrimiento que se ha publicado en la revista 'Science' e investigador del Laboratorio de la División de Biociencias Físicas de al Universidad de Berkeley (EEUU).

Además, el hallazgo supone la primera prueba de un ecosistema formado por una única especie biológica. La bacteria Desulforudis audaxviator, encontrada en una nueva galería de la mina de oro de Mponeng, cercana a Johanesburgo (Sudáfrica), en condiciones de total oscuridad y a más de 60 grados centígrados de temperatura, vive de forma totalmente aislada de otras formas de vida. Consigue sobrevivir en un hábitat semejante gracias a la energía que extrae, no del Sol, sino del hidrógeno y del sulfato producidos por la descomposición radiactiva del uranio presente en la mina. Además, como vive aislada de otras formas de vida, obtiene sus moléculas orgánicas de la humedad presente en la tierra, del carbono inorgánico de las rocas y del nitrógeno que proviene del amonio que rodea los minerales.

Largo camino por la Evolución

En el largo trayecto evolutivo hasta las profundidades de la Tierra, esta bacteria ha desarrollado una batería de genes que le permiten hacer cosas impensables en otras formas de vida, como fijar el nitrógeno directamente del elemento químico presente en el medio."Casi todos los organismos viven en comunidades con diferentes papeles dentro de cada ecosistema", dice Chivian. Pero D. audaxviator ha obtenido genes fundamentales para su vida de otros organismos, como arqueas, gracias a la capacidad de intercambiar material genético, un proceso conocido como transferencia horizontal que le permite obtener genes de organismos muy diferentes a él. Estos le permiten, no sólo alimentarse de materia inorgánica exclusivamente, sino convertirse en una espora cuando hay periodos pobres en nutrientes o protegerse a sí mismo del ataque de los virus.

No se trata de un organismo marciano, pero su modo de vida bien podría encajar con las condiciones que podría tener un organismo en Marte. Sin embargo, su procedencia no es extraterrestre, sino todo lo contrario procede del mismo corazón de la Tierra. De hecho, el nombre de la bacteria procede de la literatura de ciencia ficción del maestro Julio Verne. En un momento de su Viaje al centro de la Tierra, el protagonista, el profesor Lidenbrock, descifra un mensaje que dice en latín: "desciende, Audax viator, y alcanza el centro de la Tierra".

• La bacteria 'Desulforudis audaxviator' forma ecosistemas de una única especie
• Es capaz de vivir a 60 grados de temperatura y a 3 kilómetros de profundidad

Sarah P. Hammond, M.D., and Lindsey R. Baden, M.D.

abstract
http://content.nejm.org/cgi/content/full/359/15/e20?query=TOC

PDF
http://content.nejm.org/cgi/reprint/359/15/e20.pdf

Interactive Graphic
http://content.nejm.org/cgi/content/full/359/15/e20/DC1

M. R. Mueller1, M. K. Hayden2, S. K. Fridkin3, D. K. Warren4, L. Phillips2, K. Lolans5 and J. P. Quinn2, 5, 6

(1)  Rollins School of Public Health, Emory University, Atlanta, GA, USA
(2)  Rush University Medical Center, Chicago, IL, USA
(3)  Centers for Disease Control and Prevention, Atlanta, GA, USA
(4)  Washington University School of Medicine, St. Louis, MO, USA
(5)  Chicago Infectious Disease Research Institute, Chicago, IL, USA
(6)  Infectious Disease Division, John Stroger Hospital of Cook County, 1990 W Polk, Rm. 1236, Chicago, IL 60612, USA

Abstract  In vitro, ciprofloxacin can select for dual resistance to fluoroquinolones and imipenem in Pseudomonas aeruginosa via a mutation in the regulatory gene, mexT, which downregulates OprD and upregulates MexEF-OprN. We performed a nested case-control study of patients in two medical intensive care units participating in an observational cohort study. Patients colonized or infected with P. aeruginosa resistant to both ciprofloxacin and imipenem (cases) were compared to controls. The presence of OprD and OprN from cases was evaluated by Western blot. In total, 44 cases were compared to 132 controls. Imipenem exposure [adjusted odds ratio (AOR) = 11.4, p = 0.044] was significantly associated with case status, but fluoroquinolone use was not (AOR = 1.0, p = 0.998). Neither OprD nor OprN were detected in any isolate. Fluoroquinolone use was not a risk factor for acquisitions of dually resistant P. aeruginosa. The absence of OprN in these isolates suggests that dual resistance is not due to mexT mutations.

abstract
http://www.springerlink.com/content/y215467m2r117k48/

D. W. Wareham1, 2, 3, 6 , D. C. Bean2, P. Khanna1, 3, E. M. Hennessy4, D. Krahe1, 3, A. Ely5 and M. Millar1, 2, 3

(1)  Division of Infection, Barts and The London NHS Trust, London, UK
(2)  Centre for Infectious Disease, Institute of Cell and Molecular Science, Barts and The London, Queen Mary’s School of Medicine and Dentistry, London, UK
(3)  Department of Medical Microbiology, Homerton University Hospital NHS Foundation Trust, London, UK
(4)  Wolfson Institute of Preventive Medicine, Barts and The London, Queen Mary’s School of Medicine and Dentistry, London, UK
(5)  Intensive Care Unit, Barts and The London NHS Trust, London, UK
(6)  Centre for Infectious Disease, Institute of Cell and Molecular Science, 4 Newark Street, Whitechapel, London, E1 2AT, UK

Abstract   Acinetobacter spp. are increasingly reported as important causes of human infection. Many isolates exhibit multi-drug resistance, raising concerns over our ability to treat serious infections with these organisms. The impact of infection on clinical outcome as well as the importance of multi-drug resistance is poorly defined. A descriptive retrospective observational study was undertaken of all episodes of Acinetobacter bacteremia occurring in a UK tertiary care centre from 1998–2006. Demographics of infected patients, characteristics and antimicrobial susceptibility of infecting strains were recorded and the impact of antimicrobial therapy on all causes of 30-day mortality assessed. Three hundred ninety-nine episodes of Acinetobacter bacteremia were identified, with A. baumannii being the most frequently isolated species. Most episodes occurred in critical care and were associated with multidrug resistance, with carbapenem resistance rising from 0% in 1998 to 55% in 2006. Although bacteremia due to carbapenem-resistant Acinetobacter and a requirement for critical care were associated with a higher mortality, mortality was not reduced by the administration of appropriate empirical antimicrobial therapy. A prospective study is required to identify both the most effective intervention and those most likely to benefit from treatment.

abstract
http://www.springerlink.com/content/p2j46t5q81441586/

M. Hallin, O. Denis, A. Deplano, R. De Ryck, S. Crèvecoeur, S. Rottiers, R. de Mendonça and M. J. Struelens

Laboratoire de Référence MRSA-Staphylocoques, Department of Microbiology, Hôpital Erasme, Université Libre de Bruxelles, Brussels, Belgium

ABSTRACT
National surveillance of healthcare-associated methicillin-resistant Staphylococcus aureus (HA-MRSA) isolates by pulsed-field gel electrophoresis (PFGE) typing allowed identification of rarely occurring 'sporadic' isolates with patterns significantly distinct from those of major epidemic clones of methicillin-resistant S. aureus (MRSA) circulating in Belgian hospitals. The aim of the present study was to compare the genetic background, antibiotic susceptibility profile and in vitro growth rates of 36 MRSA isolates with either 'epidemic' or 'sporadic' PFGE profiles to identify factors that could be involved in the epidemic behaviour of S. aureus. Sequence analysis of seven housekeeping genes (multilocus sequence typing) and seven surface-associated genes, combined with staphylococcal cassette chromosome mec (SCCmec) typing and spa typing results, segregated sporadic isolates into four groups: (1) isolates phylogenetically distant from epidemic HA-MRSA clones that possessed several properties of community-acquired MRSA strains; (2) isolates derived from the same methicillin-susceptible S. aureus ancestor as epidemic isolates but possessing a distinct type of SCCmec; and (3) and (4) isolates that were closely related to epidemic strains, either as recent descendants of these or as intermediate evolutionary steps between epidemic HA-MRSA strains and their putative ancestors. Sporadic isolates did not show slower growth in vitro than epidemic isolates. These findings suggest that the SCCmec type and insertion/deletion of other mobile genetic elements may be involved in modulating the epidemic behaviour of MRSA strains of similar genetic background, independently of fitness cost.

abstract
http://www3.interscience.wiley.com/journal/120088406/abstract?CRETRY=1&SRETRY=0

J. A. Otter and G. L. French

Guy's and St Thomas' Hospital, and King's College London, London, UK
Corresponding author and reprint requests: G. L. French, Department of Infection, 5th Floor, North Wing, St Thomas' Hospital, Lambeth Palace Road, London SE1 7EH, UK

ABSTRACT
We used ciprofloxacin susceptibility as a phenotypic marker of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in a London hospital collection of MRSA isolates from inpatients, outpatients and primary-care clinics during 2000–2006. Four-hundred and fifty-eight ciprofloxacin-susceptible (Cip-S) MRSA isolates were reported; antimicrobial susceptibility, staphylococcal cassette chromosome mec (SCCmec) type, spa type and the presence of Panton–Valentine leukocidin (PVL) genes were determined for all 194 surviving Cip-S MRSA isolates. Multilocus sequence typing and pulsed-field gel electrophoresis were performed on representative isolates. Clinical and epidemiological features of Cip-S MRSA infections were consistent with CA-MRSA, the incidence of which increased markedly during the study period from 49 in 2000 to 102 in 2006. Most (82.0%) of the surviving Cip-S MRSA isolates were SCCmec IV and 25.3% were PVL-positive. Considerable clonal heterogeneity was noted among the recovered isolates, including the t044/ST80-IV European clone and the PVL-negative t127/ST1-IV clone; PVL-positive t008/ST8-IV (USA300) isolates were rare. Ciprofloxacin susceptibility is a useful screening marker of CA-MRSA strains in London, which are more frequent than previously thought and whose incidence is increasing.

abstract
http://www3.interscience.wiley.com/journal/120088408/abstract?CRETRY=1&SRETRY=0

Fernanda Lessa, MD, MPH; Sangwoo Tak, ScD, MPH; Shannon R. DeVader, MPH; Rekha Goswami, MD, MPH; Mary Anderson, RN, BSN; Ian Williams, PhD; Kathleen F. Gensheimer, MD, MPH; Arjun Srinivasan, MD

From the Division of Healthcare Quality Promotion (F.L., A.S.), the Epidemic Intelligence Service, Office of Workforce and Career Development (F.L., S.T.), and the Division of Viral Hepatitis (I.W.), Centers for Disease Control and Prevention (CDC), and the CDC/Council of State and Territorial Epidemiologists Applied Epidemiology Fellowship Program (S.R.D.), Atlanta, Georgia; the Maine Department of Human Services (S.R.D., K.F.G.) and the Togus Veterans Affairs Medical Center (R.G., M.A.), Augusta, Maine.

Objective.  A hospital discovered a lapse in the reprocessing procedures for transrectal ultrasound–guided prostate biopsy equipment. An investigation was initiated to assess the risks of transmission of hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), and bacteria during prostate biopsies.

Methods.  We offered testing for HBV, HCV, and HIV infection to patients who had undergone prostate biopsies from January 30, 2003, through January 27, 2006. We reviewed their medical records and obtained information on the reprocessing procedures that were in use at the time for the prostate biopsy equipment.

Setting.  A healthcare facility in Maine.

Results.  Of the 528 patients exposed to improperly reprocessed prostate biopsy equipment, none tested positive for HIV or HCV. Sixteen patients (3%) tested positive for past HBV infection but had no prebiopsy HBV serologic test results available (ie, transmission from improperly reprocessed biopsy equipment was possible), and 11 (2%) had evidence of postbiopsy bacterial infections. The number of cases of HBV and bacterial infections were within reported ranges for this population and were not clustered in time. Review of the reprocessing procedures in use at the time revealed that the manufacturer-recommended brushes for cleaning the reusable biopsy needle guide were never used. Brushes did not come with the equipment and had to be ordered separately.

Conclusions.  Despite the lack of evidence of pathogen transmission in this investigation, it is critical to review the manufacturer's reprocessing recommendations and to establish appropriate procedures to avert potential pathogen transmission and subsequent patient concerns. This investigation provides a better understanding of the risks associated with improperly reprocessed transrectal ultrasound prostate biopsy equipment and serves as a methodologic tool for future investigations.

abstract
http://www.journals.uchicago.edu/doi/abs/10.1086/533546

"La cadena estadounidense de cafeterías Starbucks es acusada hoy por un diario británico de malgastar 23 millones de litros de agua al día por una política de higiene que obliga a mantener abiertos ininterrumpidamente los grifos de sus 10 mil sucursales."

Por supuesto que estoy hablando del delicioso cafe mañanero; pero la noticia, me dejó frio... y es que no es posible mis estimados lectores, que por "higiene" se deje abierta una llave de agua para evitar que las bacterias se reproduzcan en sus tuberías. Son ANITICUERPOS!!!!! pero si es una verdadera chingadera el desperdiciar el agua de esa manera, habiendo tantas maneras de desinfectar  los sistemas hidráulicos...

Quizá esto no influya mucho en mi predilección por esa deliciosa bebida que suelo ingerir por las mañanas, pero ahora, lo haré a disgusto...

Espero que por lo menos en México no realicen esta estupidez.

Anne-Marie Dumas, MD; Raphaëlle Girard, MD; Louis Ayzac, MD; Geneviève Beaumont, MWc; Emmanuelle Caillat-Vallet, MSc; Florence Depaix, RNc; Chantal Gignoux, MWc; Catherine Haond, MD; Noelle Pral, MWc; Jacqueline Robert, MWc; Françoise Tissot-Guerraz, MD; Agnès Vincent-Bouletreau, MD; Michel Berland, MD; Jacques Fabry, MD

From the Service de Gynécologie Obstétrique (A.M.D., M.B.) and the Service d'Hygiène et Épidémiologie (R.G.), Centre Hospitalier Lyon Sud, Pierre Bénite, and the Centre de Coordination de la Lutte Contre les Infections Nosocomiales Sud-Est (L.A., G.B., E.C.-V., F.D., C.G., C.H., N.P., J.R., F.T.-G., A.V.-B., J.F.), Saint Genis Laval, France.

Objective.  To establish whether antibiotic prophylaxis against group B streptococcal infection may be a confounding factor in comparisons of rates of endometritis and urinary tract infection after vaginal delivery.

Design.  Prospective study.

Setting.  Maternity units at 48 hospitals in a regional surveillance network in France during 2001-2004.

Methods.  The maternity units used a common protocol to establish whether antibiotic prophylaxis was indicated. Risk factors for endometritis and urinary tract infections were evaluated using multiple logistic regression.

Results.  We analyzed 49,786 vaginal deliveries. The percentage of women receiving antibiotic prophylaxis varied widely and significantly among the maternity units (range, 4.4%-26.0%; median, 15.8%; 25th percentile, 12.1%; 75th percentile, 19.0%) ( , by Mantel-Haenszel χ2 test). The incidence rate of endometritis was significantly reduced from 0.25% to 0.11% by antibiotic prophylaxis ( ). There was a decrease in the incidence of urinary tract infection from 0.37% to 0.32%, but it was not statistically significant ( ).

Conclusions.  A reduction in the incidence of endometritis was observed when intrapartum antibiotic prophylaxis against group B streptococcal infection was used. However, the proportion of women considered to be at risk of infection varied widely among institutions. Comparisons of rates of endometritis among maternity units, but not urinary tract infection rates, should take into account antibiotic prophylaxis as a significant confounding factor.

abstract
http://www.journals.uchicago.edu/doi/abs/10.1086/529210

J. Corredoira1 , M. P. Alonso2, A. Coira2, E. Casariego1, C. Arias1, D. Alonso1, J. Pita2, A. Rodriguez2, M. J. López1 and J. Varela1

(1)  Infectious Disease Unit, Hospital Xeral-Calde, Calle Severo Ochoa S/N, Lugo, 27004, Spain
(2)  Microbiology Unit, Hospital Xeral-Calde, Lugo, Spain

Abstract  The purpose of this study was to evaluate the characteristics of infective endocarditis (IE) caused by S. bovis and compare them to those caused by streptococci of the viridans group (SVG). A prospective study was undertaken considering 55 consecutive cases of IE due to S. bovis and 41 to SVG over 18 years. The study was divided into two periods (1988–1996 and 1997–2005). S. bovis caused 24% of the IE in our centre and constituted the main aetiology for this disease, showing an increase of 358% during the second period studied. Biotype I was responsible for 94.5% of cases and there was a high degree of association with colon tumours (53%). Over the period of the study, 107 patients admitted to our hospital had bacteraemia caused by S. bovis and 310 patients had bacteraemia caused by SVG. In the first group, 55 (51%) were endocarditis cases, but only 41 (13%) of the patients with SVG bacteraemia had endocarditis (p < 0.0001).

The distinguishing features of endocarditis caused by S. bovis in comparison with those caused by SGV were: a greater increase in cases during the 2nd period studied (from 12 to 43 vs. from 19 to 22, p < 0.01), a higher percentage of males (93% vs. 71%, p < 0.004), patients significantly older (median age 66 vs. 58.5, p < 0.004), less predisposing cardiopathy (42% vs. 76%, p < 0.0009), more bivalvular involvement (42% vs. 22%, p < 0.04), more spondylitis (9% vs. 0%, p < 0.04), a higher association with colonic tumours (53% vs. 5%, p < 0.0001), and a higher percentage of antibiotic resistance: erythromycin 66% vs. 19%, p < 0.0001; clindamycin 67% vs. 11%, p < 0.0001; cotrimoxazole 77% vs. 30.5%, p < 0.0001, respectively. IE due to S. bovis is an emergent disease in our environment, presenting different characteristics to those produced by SVG

abstract
http://www.springerlink.com/content/m35485920786r025/

Mignon du Plessis,1,2* Anne von Gottberg,1,2 Cheryl Cohen,1,3 Linda de Gouveia,1 Keith P. Klugman,1,4 for the Group for Enteric Respiratory and Meningeal Disease Surveillance in South Africa (GERMS-SA)

National Institute for Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS),1 School of Pathology,2 School of Public Health, University of the Witwatersrand, Johannesburg, South Africa,3 Hubert Department of Global Health, Rollins School of Public Health, and Division of Infectious Diseases, School of Medicine, Emory University, Atlanta, Georgia4

Neisseria meningitidis strains (meningococci) with decreased susceptibility to penicillin (MICs, >0.06 µg/ml) have been reported in several parts of the world, but the prevalence of such isolates in Africa is poorly described. Data from an active national laboratory-based surveillance program from January 2001 through December 2005 were analyzed. A total of 1,897 cases of invasive meningococcal disease were reported, with an average annual incidence of 0.83/100,000 population. Of these cases, 1,381 (73%) had viable isolates available for further testing; 87 (6%) of these isolates tested intermediately resistant to penicillin (Peni). Peni meningococcal isolates were distributed throughout all provinces and age groups, and there was no association with outcome or human immunodeficiency virus infection. The prevalence of Peni was lower in serogroup A (7/295; 2%) than in serogroup B (24/314; 8%), serogroup C (9/117; 8%), serogroup Y (22/248; 9%), or serogroup W135 (25/396; 6%) (P = 0.02). Pulsed-field gel electrophoresis grouped 63/82 Peni isolates into nine clusters, mostly according to serogroup. The clustering of patterns from Peni isolates was not different from that of penicillin-susceptible isolates. Twelve sequence types were identified among 18 isolates arbitrarily selected for multilocus sequence typing. DNA sequence analysis of the penA gene identified 26 different alleles among the Peni isolates. Intermediate penicillin resistance is thus widespread among meningococcal serogroups, has been selected in a variety of lineages, and, to date, does not appear to be associated with increased mortality. This is the first report describing the prevalence and molecular epidemiology of Peni meningococcal isolates from sub-Saharan Africa.

abstract
http://jcm.asm.org/cgi/content/abstract/46/10/3208

Los autores de este trabajo informan:

La colisión de asteroides y meteoritos sobre la superficie terrestre se ha correlacionado con extinciones masivas. Sin embargo, algunos modelos consideran un escenario en el que la vida puede pasar de un planeta a otro por parte de rocas lanzadas al espacio tras el impacto de un asteroide. Esta posibilidad ha sido llamada litopanspermia en referencia a la teoría de la panspermia formulada por Arrhenius (1903). Mientras que la panspermia postula que microscópicas formas de vida, tales como esporas, pueden ser diseminadas por el viento solar, llevando formas de vida de un planeta a otro, la litopanspermia asume que las rocas lanzadas al espacio tras el impacto de un meteoro sirve para transferir organismos residentes en esas rocas.

La posibilidad de la existencia de agua en Marte ha abierto la especulación de que quizás en algún momento ese planeta pudo albergar alguna forma de vida. Además, han existido transferencia de material entre Marte y la Tierra, tal y como muestran los 40 meteoritos marcianos encontrados en nuestro planeta hasta este momento. Estos meteoritos están formados exclusivamente de rocas ígneas, que incluyen variedades de rocas plutónicas y volcánicas, tales como basalto, piroxenos o dunitas. La época de cristalización es muy variada, desde 180 millones de años (Ma), 360-600 Ma a 1300 Ma. Solamente se ha encontrado un ejemplo de meteorito con una antigüedad de 4500 Ma. Se han llevado a cabo estudios petrográficos para estudiar el metamorfismo provocado por impactos y éstos han mostrado que la fuerza necesaria para su lanzamiento fuera de la órbita del planeta oscila en un mínimo de 5-10 GPa, hasta un máximo de 55 GPa.

Por supuesto, una transferencia viable de microorganismos entre planeta requiere, no sólo que éstos sobrevivan al escape (al impacto más el lanzamiento al espacio), sino también al viaje a través del espacio, así como sobrevivir al proceso de entrada en la atmósfera terrestre. Estudios previos mostraron que esporas de Bacillus subtilis podían vivir es un ambiente hostil, similar al espacio exterior, por un máximo de 6 años, teniendo en cuenta que estas esporas estuvieron protegidas de la radiación UV del sol. Cabe la posibilidad de que estas esporas pudieran ser capaces de resistir radiación UV, o exposición al vacío permitiendo así un tránsito viable entre Marte y la Tierra (y viceversa) en el interior de rocas mayores a 1 metro. Este acontecimiento pudo ocurrir varias veces a lo largo de la historia del Sistema Solar.

No hay ningún estudio acerca de la capacidad de sobrevivir de las bacterias que pueden colonizar el interior de las rocas a impactos similares a una colisión por meteoritos. En el trabajo que aquí se presenta se estudia la capacidad de supervivencia de bacterias incluidas en rocas similares a las marcianas (gabro) a la presión que sufren los meteoritos marcianos.

Los microorganismos elegidos fueron: (i) endosporas bacterianas de Bacillus, una de las entidades vivas más resistentes a condiciones ambientales adversas, (ii) una cianobacteria resistente a la desecación y a la radiación ionizante, Chroococcidiopsis y el liquen Xanthoria elegans, habitante de ambos polos y adaptado a condiciones extremas tales como fuertes fluctuaciones de temperatura, desecación extrema y elevada radiación UV.

La cianobacteria Chroococcidiopsis en su ambiente natural, colonizando una roca del desierto del Negev como un delgado biofilm endolítico

El liquen Xanthoria elegans colonizando en una roca de los Alpes

El objetivo de este estudio es comprobar si microorganismos endolíticos (incluidos en rocas) lanzados al espacio pueden sobrevivir a las condiciones que ello requiere: presiones de choque de 5-55 GPa y rápidos aumentos de temperatura desde 1 grado kelvin a 1000 grados kelvin.

Esquema (A) y fotografía (B) del sistema que simula mediante potentes explosiones controladas las presiones predichas en un impacto meteorítico

Los resultados de este experimento mostraron que tanto las esporas de Bacillus como las muestras del liquen Xanthoria podían sobrevivir a los tratamientos de presión y temperatura a los que fueron sometidos, mientras que Chroococcidiopsis es susceptible a presiones mayores a 10 GPa. Como resumen, en las condiciones predichas que acontecen en impactos de meteoros y lanzamiento de material rocoso fuera de un planeta, es posible la supervivencia, y por tanto la transferencia de microorganismos entre diferentes entidades planetarias. Sin embargo, esa transferencia parece no ser válida para cianobacterias.

Olivier Dauwalder,1,2,3 Gérard Lina,1,2,3 Géraldine Durand,1,2,3 Michèle Bes,1,2,3 Hélène Meugnier,1,2,3 Vincent Jarlier,4 Bruno Coignard,5 François Vandenesch,1,2,3 Jerome Etienne,1,2,3 and Frédéric Laurent1,2,3*

Université Lyon, Centre National de Référence des Staphylocoques, F-69622, Lyon, France,1 INSERM, U851, F-69370, Lyon, France,2 Hospices Civils de Lyon, F-69004, Lyon, France,3 Laboratoire de Bactériologie-Hygiène, UFR de Médecine Pierre et Marie Curie Paris VI, Paris, France,4 Département des Maladies Infectieuses, Institut de Veille Sanitaire, F-95000, Saint-Maurice, France5

We conducted a prospective multicenter study of methicillin-resistant Staphylococcus aureus (MRSA) isolates, including the first five consecutive clinical isolates, collected between September 2006 and February 2007 in 23 hospitals located throughout France (Fig. 1). The 111 isolates were tested for their antibiotic susceptibility patterns and were extensively characterized by screening for drug resistance and agr alleles, multilocus sequence typing (ST), staphylococcal cassette chromosome mec (SCCmec) typing, spa typing, and PCR profiling of 21 toxin genes. Clones were designated by their ST followed by their SCCmec type (I to VI). The Lyon clone ST8-IV or ST8-IVvariant (n = 77; 69.4%) was widely distributed. Four minor clones were also detected, namely, the "classical" Pediatric clone ST5-IV (n = 9; 8.1%), the "new" Pediatric clone ST5-VI (n = 8; 7.2%), the clone Geraldine ST5-Itruncated (n = 7; 6.3%), and the European clone ST80-IV (n = 4; 3.6%). The six other isolates were related to five rare clones. Relative to that of other European countries, the situation in France is marked by the predominance of a specific major clone and the worrying emergence of minor clones with enhanced virulence and new antibiotic susceptibility profiles.

abstract
http://jcm.asm.org/cgi/content/abstract/46/10/3454

David A. Talan,1,2 Anusha Krishnadasan,1 Fredrick M. Abrahamian,1 Walter E. Stamm,3 and Gregory J. Moran,1,2 for the EMERGEncy ID NET Study Groupa

1Department of Emergency Medicine, 2Division of Infectious Diseases, David Geffen School of Medicine at University of California–Los Angeles (UCLA), Olive View-UCLA Medical Center, Sylmar; and 3Department of Medicine, Division of Infectious Diseases, University of Washington Medical Center, University of Washington School of Medicine, Seattle

Background.  High rates of resistance to trimethoprim-sulfamethoxazole (TMP-SMX) among uropathogenic Escherichia coli are recognized, and concerns exist about emerging fluoroquinolone resistance.

Methods.  Adults presenting to 11 US emergency departments with (1) flank pain and/or costovertebral tenderness, (2) temperature >38°C, and (3) a presumptive diagnosis of pyelonephritis were enrolled; patients for whom 1 uropathogen grew on culture were analyzed. Epidemiologic and clinical data were collected at the time of care. The prevalence of E. coli in vitro antibiotic resistance and risk factors associated with TMP-SMX–resistant E. coli infection were determined.

Results.  Among 403 women with uncomplicated pyelonephritis caused by E. coli, the mean site rate of E. coli resistance to TMP-SMX was 24% (range, 13%–45%). Mean site rates of E. coli resistance to ciprofloxacin and levofloxacin were 1% and 3%, respectively. Only TMP-SMX exposure within 2 days before presentation and Hispanic ethnicity were associated with E. coli resistance to TMP-SMX (compared with resistance rates of 20% among women lacking these risk factors); antibiotic exposure within 3–60 days before presentation, health care setting exposure within 30 days before presentation, history of urinary tract infections, and age >55 years were not associated with E. coli resistance to TMP-SMX. Among 207 patients with complicated pyelonephritis, mean site rates of E. coli resistance to ciprofloxacin and levofloxacin were 5% and 6%, respectively.

Conclusions.  These results suggest that the prevalence of TMP-SMX–resistant infection among patients with uncomplicated pyelonephritis is 20% in many areas of the United States, and risk stratification cannot identify patients at low risk of infection. Rates of fluoroquinolone-resistant E. coli infection appear to be low among patients with uncomplicated pyelonephritis but higher among those with complicated infections. Fluoroquinolones should remain to be the preferred empirical treatment for women with uncomplicated pyelonephritis.

abstract
http://www.journals.uchicago.edu/doi/abs/10.1086/592250

O. Murillo,1* M. E. Pachón,1 G. Euba,1 R. Verdaguer,2 F. Tubau,2 C. Cabellos,1 J. Cabo,3 F. Gudiol,1 and J. Ariza1

Laboratory of Experimental Infection, Infectious Diseases Service,1 Microbiology Department,2 Orthopaedic Surgery Department, IDIBELL, Hospital Universitari de Bellvitge, Feixa Llarga s/n, Barcelona 08907, Spain3

Since levofloxacin at high doses was more active than levofloxacin at conventional doses and was the best therapy alone in a rat model of staphylococcal foreign-body infection, in this study we tested how these differences affect the activities of their respective combinations with rifampin in vitro and in vivo. In vitro studies were performed in the log and stationary phases.

By using this model, rifampin at 25 mg/kg of body weight/12 h, levofloxacin at 100 mg/kg/day, levofloxacin at 100 mg/kg/day plus rifampin, levofloxacin at 50 mg/kg/day, levofloxacin at 50 mg/kg/day plus rifampin, or a control treatment was administered for 7 days; and therapy with for levofloxacin at 100 mg/kg/day alone and rifampin alone was prolonged to 14 days. We screened for the appearance of resistant strains. Killing curves in the log phase showed a clear antagonism with levofloxacin at concentrations 2x MIC and rifampin and tended to occur in the stationary phase. At the end of 7 days of therapy, levofloxacin at 100 mg/kg/day was the best treatment and decreased the bacterial counts from tissue cage fluid (P < 0.05 compared with the results for groups except those receiving rifampin alone). At the end of 14 days of therapy with levofloxacin at 100 mg/kg/day, levofloxacin at 100 mg/kg/day plus rifampin, and the control treatment, the bacterial counts on the coverslips were 2.24 (P < 0.05 compared with the results with the combined therapy), 3.36, and 5.4 log CFU/ml, respectively. No rifampin or levofloxacin resistance was detected in any group except that receiving rifampin alone. In conclusion, high-dose levofloxacin was the best treatment and no resistant strains appeared; the addition of rifampin showed an antagonistic effect. The efficacy of the rifampin-levofloxacin combination is not significantly improved by the dosage of levofloxacin.

abstract
http://aac.asm.org/cgi/content/abstract/52/10/3681

ISABEL F. LANTIGUA. El Mundo

Saltó a la fama en 1981, como responsable de la enfermedad del sida, pero antes de salir a la luz pública, el virus de la inmunodeficiencia humana (VIH) ya había infectado a muchos habitantes, principalmente de África. El análisis de una muestra de 1960 de una mujer seropositiva de Kinshasa (República Democrática del Congo) ha permitido a un equipo de investigadores de los cuatro continentes averiguar que la cepa del virus más extendida en el mundo comenzó a propagarse entre los humanos entre 1884 y 1924, y no durante los años 30 como se creía hasta ahora.

En un trabajo que bien podría firmar el mismísimo Indiana Jones, el equipo ha seguido el rastro arqueológico del virus para descubrir su origen centenario. El fragmento que han logrado analizar (bautizado como DRC60) supone la segunda muestra más antigua del VIH que se conoce. La primera, obtenida hace 10 años, es la ZR59 y procede de un hombre también de Kinshasa. Con las dos sobre la mesa, han podido llevar a cabo el primer estudio genético comparativo de las antiguas cepas del virus y descubrir cuándo empezó a diversificarse. Sus resultados los publican en la revista Nature.

¿Qué han descubierto? Pues que los genomas de ambas muestras se diferencian en un 12% pero ambas partieron del mismo virus, el del grupo M, responsable del 95% de los casos de sida del mundo. "Dado que cada subtipo del virus requiere varias décadas de evolución independiente en los humanos, las divergencias encontradas en las muestras, que se llevan tan sólo un año, indican que tienen un ancestro común que empezó a diversificarse mucho tiempo antes, a comienzos de siglo XX", señala Michael Worobey, coordinador del trabajo de la Universidad de Tucson en Arizona (EEUU).

La explicación más simple para la propagación de este primer virus es que "saltó de los chimpancés a los humanos, seguramente a través de las exposición de los individuos a la sangre de estos animales, a los que cazaban furtivamente para alimentarse de su carne", aclara en un comentario Paul Sharp, del Instituto de Biología de la Evolución de la Universidad de Edimburgo. Los investigadores señalan que "la reserva de este virus ancestral, antes de su evolución, todavía se puede encontrar entre comunidades de chimpancés salvajes en la misma área del continente africano, en la República Democrática del Congo".

Crecimiento de las ciudades

Según el trabajo, la propagación del virus en esa época coincide con las primeras aglomeraciones urbanas en África central y con el asentamiento de las primeras colonias europeas en el lugar. Este crecimiento facilitó la transmisión del VIH. Como explica Paul Sharp, "Kinshasa (en aquella época Leopoldville) no fue sólo la mayor de estas ciudades que empezaron a surgir sino también una ruta de escape del virus hacia Camerún y otros lugares". Anthony Fauci, director de los Institutos de Alergia y Enfermedades Infecciosas de EEUU, que han financiado la investigación, declara a elmundo.es que "hasta ahora se pensaba que el virus comenzó a propagarse en humanos alrededor de 1939, pero gracias a este estudio descubrimos que ya estaba presente tres décadas antes".
"Descubrir la historia genética del VIH y cómo ha evolucionado da a los científicos un conocimiento más veraz sobre cómo puede mutar el virus en el futuro. Estas investigaciones pueden ayudar a desarrollar nuevas terapias y estrategias de prevención eficaces", añade Fauci.

Imagen de Kinshasa datada entre 1883 y 1885, poco después de su fundación. (Foto: Nature)

Letter

Maria C. Martín, Francisco Pérez, Alfonso Moreno, Alberto Moral, Miguel A. Alvarez, Francisco J. Méndez, and Fernando Vázquez

Instituto de Productos Lácteos de Asturias, Spain (M.C. Martín, M.A. Alvarez); Hospital Universitario Central de Asturias, Oviedo, Spain (F. Pérez, A. Moreno, A. Moral, F.J. Méndez); Facultad de Medicina Area de Microbiología, Oviedo (F.J. Méndez, F. Vázquez); and Hospital Monte Naranco, Oviedo (F. Vázquez)

FREE Full Text
http://www.cdc.gov/eid/content/14/10/1672.htm

PDF
http://www.cdc.gov/eid/content/14/10/pdfs/1672.pdf

MADRID.- Investigadores del Centro Superior de Investigaciones Científicas (CSIC) han diseñado un nuevo método para detectar las enfermedades vegetales antes de que aparezcan los primeros síntomas.

La técnica, basada en la medición de fluorescencia emitida a varias longitudes de onda (roja, azul y verde), está pensada para su aplicación en el sector agrícola, donde podría ayudar a evitar pérdidas millonarias.

Los investigadores han probado el método con el virus del moteado suave del pimiento, causante de una de las enfermedades más dañinas del sector agrícola.

Los distintos colores (longitudes de onda) traducen el estado de salud de la planta. La fluorescencia roja indica una infección; la azul y la verde reflejan funciones de defensa de la planta frente al ataque del patógeno.

"Cuando las plantas son infectadas, reducen su capacidad fotosintética y la radiación solar que reciben resulta entonces excesiva. Como mecanismo defensivo, la planta puede disipar parte de esa energía como fluorescencia roja, emitida por la clorofila", explica la investigadora Matilde Barón Ayala, de la Estación Experimental del Zaidín en Granada, del CSIC.

Las imágenes de las fluorescencias se obtienen irradiando con luz las hojas infectadas. La radiación emitida se recoge con una cámara de vídeo dotada de filtros especiales. Las fluorescencias aparecen en blanco y negro, pero se combinan para crear una nueva imagen en una escala de colores falsos para facilitar su lectura.

Agricultura de precisión

Según el CSIC, es la primera vez que una técnica de este tipo es empleada para el diagnóstico de una infección sistémica, es decir, que afecta a todo el vegetal. Pero además de permitir el diagnóstico, el método proporciona información sobre el movimiento del patógeno dentro de la planta y su mecanismo de acción.

La técnica puede ser utilizada tanto a nivel microscópico, en mediciones a pie de campo, como a través de satélite para obtener imágenes de grandes extensiones de terreno.

Supone, en este sentido, un paso más hacia la "agricultura de precisión".

"El sistema puede aplicarse a cualquier tipo de enfermedad producida por virus, bacterias, hongos e incluso pequeños herbívoros". Esto incluye, dice el CSIC, enfermedades como la tuberculosis del olivo y otras producidas por bacterias del género 'Pseudomonas', así como las producidas por hongos como el oidio en cereales o el mildiu en la vid.

El método también puede combinarse con la obtención de imágenes termales, que sería como medirle la fiebre a las plantas: las infecciones también suelen incrementar la temperatura de los vegetales.

Con información del diario español El Mundo

Letter

Jacob Strahilevitz, Amos Adler, Gillian Smollan, Violeta Temper, Nathan Keller, and Colin Block

Hadassah-Hebrew University Medical Center, Jerusalem, Israel (J. Strahilevitz, A. Adler, V. Temper, C. Block); and The Chaim Sheba Medical Center, Tel Hashomer, Israel (G. Smollan, N. Keller)

FREE Full Text
http://www.cdc.gov/eid/content/14/10/1667.htm

PDF
http://www.cdc.gov/eid/content/14/10/pdfs/1667.pdf