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1.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 42(4): 179-186, Abr. 2024. graf, tab
Artículo en Español | IBECS | ID: ibc-232172

RESUMEN

Introducción: Streptococcus pneumoniae causa enfermedades graves en la población susceptible. La vacuna neumocócica conjugada (PCV) 13-valente (PCV13) se incluyó en el calendario infantil en 2011. Este estudio analiza la evolución de los serotipos de neumococo y de sus resistencias tras la PCV13. Métodos: Se incluyeron los neumococos serotipados en Galicia en 2011-2021. Se estudió la sensibilidad antibiótica siguiendo criterios EUCAST. Se analizaron los datos en 3 subperíodos: inicial (2011-2013), medio (2014-2017) y final (2018-2021). Se calcularon las prevalencias de los serotipos y el porcentaje de resistencia a los antibióticos más representativos. Resultados: Se incluyeron 2.869 aislados. Inicialmente el 42,7% presentaba tipos capsulares incluidos en la PCV13, frente al 15,4% al final. Los incluidos en la PCV20 y no en la PCV13 y PCV15 fueron el 12,5% inicialmente y el 41,3% al final. El 26,4% de los serotipos a lo largo del estudio no estaban incluidos en ninguna vacuna. La prevalencia del serotipo 8 se multiplicó casi por 8 y la del 12F se triplicó. El serotipo 19A fue el más resistente inicialmente. La resistencia de los serotipos 11A y 15A aumentó a lo largo del estudio. Conclusiones: La introducción de la PCV13 en la población infantil determinó un cambio en los serotipos de neumococo hacia los incluidos en la PCV20 y los no incluidos en ninguna vacuna. El serotipo 19A inicialmente fue el más resistente, y el 15A, no incluido en ninguna vacuna, merece un especial seguimiento. El serotipo 8, que fue el que más se incrementó, no mostró resistencia destacable.(AU)


Introduction: Streptococcus pneumoniae causes serious diseases in the susceptible population. The 13-valent pneumococci conjugate vaccine (PCV13) was included in the children's calendar in 2011. The objective of the study was to analyze the evolution of pneumococcal serotypes and their resistance after PCV13. Methods: This study included the pneumococci serotyped in Galicia in 2011-2021. Antibiotic susceptibility was analyzed following EUCAST criteria. The data was analyzed in 3 sub-periods: initial (2011-2013), middle (2014-2017) and final (2018-2021). The prevalence of serotypes and their percentage of resistance to the most representative antibiotics were calculated. Results: A total of 2.869 isolates were included. Initially, 42.7% isolates presented capsular types included in PCV13, compared to 15.4% at the end. Those included in PCV20 and not in PCV13 and PCV15 were 12.5% at baseline and 41.3% at the end; 26.4% of the isolates throughout the study had serotypes not included in any vaccine. The prevalence of serotype 8 multiplied almost by 8 and that of 12F tripled. The 19A serotype was initially the most resistant, while the resistance of serotypes 11A and 15A increased throughout the study. Conclusions: The introduction of PCV13 in the pediatric population determined a change in pneumococcal serotypes towards those included in PCV20 and those not included in any vaccine. Serotype 19A was initially the most resistant and the 15A, not included in any vaccine, deserves special follow-up. Serotype 8, which increased the most, did not show remarkable resistance.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Niño , Streptococcus pneumoniae/genética , Farmacorresistencia Microbiana , Infecciones Neumocócicas , Prevalencia , Serogrupo , España , Enfermedades Transmisibles , Microbiología
2.
Enferm Infecc Microbiol Clin (Engl Ed) ; 42(4): 179-186, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37117145

RESUMEN

INTRODUCTION: Streptococcus pneumoniae causes serious diseases in the susceptible population. The 13-valent pneumococci conjugate vaccine (PCV13) was included in the children's calendar in 2011. The objective of the study was to analyze the evolution of pneumococcal serotypes and their resistance after PCV13. METHODS: This study included the pneumococci serotyped in Galicia in 2011-2021. Antibiotic susceptibility was analyzed following EUCAST criteria. The data was analyzed in 3 sub-periods: initial (2011-2013), middle (2014-2017) and final (2018-2021). The prevalence of serotypes and their percentage of resistance to the most representative antibiotics were calculated. RESULTS: A total of 2.869 isolates were included. Initially, 42.7% isolates presented capsular types included in PCV13, compared to 15.4% at the end. Those included in PCV20 and not in PCV13 and PCV15 were 12.5% at baseline and 41.3% at the end; 26.4% of the isolates throughout the study had serotypes not included in any vaccine. The prevalence of serotype 8 multiplied almost by 8 and that of 12F tripled. The 19A serotype was initially the most resistant, while the resistance of serotypes 11A and 15A increased throughout the study. CONCLUSIONS: The introduction of PCV13 in the pediatric population determined a change in pneumococcal serotypes towards those included in PCV20 and those not included in any vaccine. Serotype 19A was initially the most resistant and the 15A, not included in any vaccine, deserves special follow-up. Serotype 8, which increased the most, did not show remarkable resistance.


Asunto(s)
Infecciones Neumocócicas , Streptococcus pneumoniae , Humanos , Niño , Serogrupo , Antibacterianos/farmacología , España/epidemiología , Vacunas Neumococicas , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/prevención & control
3.
Rev. esp. quimioter ; 36(6): 597-603, dec. 2023. tab, graf
Artículo en Español | IBECS | ID: ibc-228246

RESUMEN

Introducción. El uso de vacunas conjugadas frente a Streptococcus pneumoniae ocasiona cambios en la epidemio logía de la Enfermedad Neumocócica Invasiva (ENI). El objetivo de este estudio fue analizar la evolución de los serotipos de S. pneumoniae aislados en el Hospital Universitario de Getafe entre 2008 y 2022. Material y métodos. Se estudiaron 313 cepas de S. pneu moniae. El serotipado se realizó mediante el test de aglutina ción por látex (Pneumotest-latex) y la reacción de Quellung. Además, se determinó la concentración mínima inhibitoria (CMI) frente a penicilina, eritromicina y levofloxacino por el método de gradiente de concentración (E-test) según los cri terios de corte EUCAST. Resultados. Los serotipos más frecuentes en todo el pe riodo de estudio fueron 8, 3, 19A, 1, 11A y 22F correspondien do con el 46,6 % de los aislados. Durante los años 2008-2012, los serotipos 3, 1, 19A, 7F, 6C y 11A supusieron en conjunto el 53,6% de los aislamientos. Entre 2013 y 2017 los serotipos 3, 8, 12F, 19A, 22F y 19F representaron el 51% de los aislados. Entre 2018-2022 los serotipos 8, 3, 11A, 15A, 4 y 6C incluyeron al 55,5% de los casos. En total, 5 cepas (1,6%) se mostraron resistentes a penicilina, 64 (20,4%) resistentes a eritromicina y 11 (3,5%) resistentes a levofloxacino. Los niveles de CMI50 y CMI90 frente a los tres antibióticos se mantuvieron estables a lo largo del tiempo. Conclusiones. El uso de vacunas conjugadas condicionó un descenso de los serotipos cubiertos junto con un aumento de los no vacunales. Los patrones de sensibilidad a eritromicina y levofloxacino se mantuvieron relativamente estables. La re sistencia a penicilina fue muy baja, no encontrándose este tipo de cepas resistentes en el último periodo de estudio (AU)


Introduction. The use of conjugate vaccines against Streptococcus pneumoniae originates changes in the invasive pneumococcal disease (IPD). The aim of this study was to in vestigate the evolution of S. pneumoniae serotypes isolated in the Hospital Universitario de Getafe between 2008 and 2022. Material and Methods. 313 of S. pneumoniae strains were studied. Serotyping was carried out by latex agglutina tion (Pneumotest-latex) and the Quellung reaction. In addi tion, the minimal inhibitory concentration (MIC) was deter mined against penicillin, erythromycin and levofloxacin by the concentration gradient method (E-test) according the EUCAST breakpoints. Results. The most frequent serotypes throughout the study period were 8, 3, 19A, 1, 11A and 22F corresponding to 46.6% of the isolates. Along 2008-2012 the serotypes 3, 1, 19A, 7F, 6C and 11A represented altogether 53.6% of the isolates. Between 2013 and 2017 the serotypes 3, 8, 12F, 19A, 22F and 19F grouped 51% of the isolates. During 2018-2022 the serotypes 8, 3, 11A, 15A, 4 and 6C included the 55.5% of the cases. In total 5 strains (1.6%) were penicillin resistant, 64 (20.4%) erythromycin resistant and 11 (3.5%) levofloxacin re sistant. The MIC50 and MIC90 levels maintained stables along the time. Conclusion. The conjugate vaccines use with different se rotype coverage conditioned a decrease of the vaccine-includ ed and an increase of non-covered. Despite these changes, the global antimicrobial susceptibility patterns to erythromycin and levofloxacin maintained relatively stables. The resistance a penicillin was low, not finding this type of resistant strains in the last study period (AU)


Asunto(s)
Humanos , Infecciones Neumocócicas/microbiología , Infecciones Neumocócicas/prevención & control , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/aislamiento & purificación , Vacuna Neumocócica Conjugada Heptavalente/administración & dosificación , Vacuna Neumocócica Conjugada Heptavalente/inmunología , Hospitales Públicos , España
4.
Artículo en Inglés | MEDLINE | ID: mdl-37945464

RESUMEN

INTRODUCTION: The introduction of pneumococcal conjugate vaccine (PCV) into childhood vaccination programmes has reduced the prevalence of vaccine serotypes (VTs) that cause invasive pneumococcal disease (IPD) in children. In the elderly population, an impact has also been seen through indirect protection (herd effect). The aim of this study was to estimate the changes in serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae isolates recovered from adult IPD and to evaluate the indirect effect of immunization with PCV10 based on laboratory records by analyzing the period from 2005 to 2019 for six years before and eight years after the universal PCV10 administration to Colombian children. METHODS: A total of 2204 S. pneumoniae isolates from adults (≥50 years) with IPD were analyzed. The analysis examined the percentage changes in proportions (prevalence) and percentage variations in population rates (annual reported rates - ARR) of VTs between the pre-PCV10 (2005-2009) and post-PCV10 (2015-2019) periods. RESULTS: The findings were (1) evidence of a significant percentage decrease of pneumococcal VT10 causing IPD in adults (50% pre-PCV10 and 16% post-PCV10); (2) significant increase of serotype 19A (from 1.6% to 14.8%) and less important increase of serotype 3 (from 10.5% to 14.5%) and non-vaccine serotypes (NVT) (from 21.4% to 38.4%) non-significant; and (3) meningitis and non-meningitis multidrug resistant isolates associated with serotype 19A. An improvement in the surveillance system is associated with the immunization of children, as noted by the increased ARRs across the analysis period. CONCLUSIONS: Our results show the indirect impact of PCV10 vaccination in children on the VT10 distribution and antimicrobial resistance of S. pneumoniae causing IPD in Colombian adults over 50 when comparing the pre-PCV10 (2005-2009) and post-PCV10 (2015-2019) periods.

5.
Rev. ADM ; 80(4): 214-219, jul.-ago. 2023. ilus, tab
Artículo en Español | LILACS | ID: biblio-1526847

RESUMEN

La microbiota oral está conformada por diversas especies bacterianas que en condiciones normales desempeñan una función protectora del huésped; sin embargo, cuando existe un desequilibrio en el ecosistema, estos microorganismos son capaces de producir diversas manifestaciones como lo es el caso de la caries dental, enfermedad infecciosa producida principalmente por Streptococcus mutans, patógeno capaz de desmineralizar los tejidos duros del diente mediante la fermentación de hidratos de carbono obtenidos de la dieta. Se ha identificado en la pared celular de este microorganismo ocho serotipos que intervienen en la adhesión, agregación y coagregación bacteriana. En los seres humanos S. mutans presenta los serotipos c, e y f, siendo el serotipo c el más prevalente a nivel mundial, el cual se conoce que está asociado a pacientes sanos, a diferencia del e y f que son capaces de invadir las células endoteliales de las arterias coronarias. No obstante, en los últimos años se ha logrado identificar el serotipo k que de igual manera presenta alta capacidad de invadir el endotelio humano, actuando en la patogénesis de las enfermedades cardiovasculares. El objetivo de la presente revisión bibliográfica es lograr cuantificar los serotipos prevalentes de S. mutans en América Latina (AU)


The oral microbiota is made up of various bacterial species that under normal conditions perform a protective function of the host, however, when there is an imbalance in the ecosystem, these microorganisms are capable of producing various manifestations such as caries, an infectious disease. produced mainly by Streptococcus mutans, a pathogen capable of demineralizing the hard tissues of the tooth through the fermentation of carbohydrates obtained from the diet. Eight serotypes involved in bacterial adhesion, aggregation and coaggregation have been identified in the cell wall of this microorganism. In humans, S. mutans presents serotypes c, e, and f, serotype c being the most prevalent worldwide, which is known to be associated with healthy patients, unlike e and f, which are capable of invading the endothelial cells of the coronary arteries. However, in recent years it has been possible to identify serotype k, which also has a high capacity to invade the human endothelium, acting in the pathogenesis of cardiovascular diseases. The objective of this literature review is to quantify the prevalent serotypes of S. mutans in Latin America (AU)


Asunto(s)
Humanos , Streptococcus mutans , Caries Dental/microbiología , Serogrupo , Adhesión Bacteriana , América Latina/epidemiología
6.
Ginecol. obstet. Méx ; 90(4): 364-370, ene. 2022. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1385034

RESUMEN

Resumen INTRODUCCION: El dengue es causado por un virus perteneciente a la familia Flaviviridae; existen cuatro serotipos relacionados: DENV-1, DENV-2, DENV-3, DENV-4 trasmitidos por picadura del mosquito hembra de las especies Aedes aegypti y Aedes albopictus. CASO CLÍNICO: Paciente de 19 años, con 36 semanas de embarazo por fecha de la última menstruación y diagnóstico de dengue por serología positiva (Ag-NS1) y trombocitopenia (68,000/mm3). El padecimiento se inició con fiebre de 38.0°C, de tres días de evolución acompañado de artralgias, mialgias, dolor retro ocular y contracciones uterinas. La paciente se ingresó al área de terapia intensiva debido a insuficiencia respiratoria (que ameritó ventilación mecánica invasiva), insuficiencia renal aguda y hematológica, posterior a cesárea. Ameritó reintervención quirúrgica por sangrado intrabdominal por trastornos de la coagulación. Durante su estancia hospitalaria requirió 50 concentrados plaquetarios, 8 concentrados eritrocitarios, 14 plasmas frescos y 4 aféresis plaquetarias. Después de 14 días de estancia hospitalaria se dio de alta por mejoría clínica. CONCLUSIÓN: Si no se actúa inmediatamente, el dengue grave es una causa de desenlace fatal madre-hijo. La identificación oportuna de las complicaciones agregadas a esta enfermedad en la embarazada denota la importancia de la prevención, el diagnóstico temprano y su tratamiento. De igual manera, es importante que en pacientes embarazadas con esta comorbilidad el servicio de Obstetricia intervenga oportunamente en la vigilancia pre y posquirúrgica.


Abstract BACKGROUND: Dengue is caused by a virus belonging to the Flaviviridae family, there are four related serotypes: DENV-1, DENV-2, DENV-3, DENV-4 transmitted by the bite of the female mosquito of the species Aedes aegypti and Aedes albopictus. CLINICAL CASE: 19-year-old female patient, 36 weeks pregnant by date of last menstrual period and diagnosed with dengue due to positive serology (Ag-NS1) and thrombocytopenia (68,000/mm3). The illness started with fever of 38.0°C, of three days of evolution accompanied by arthralgias, myalgias, retro ocular pain and uterine contractions. The patient was admitted to the intensive care unit due to respiratory failure (which required invasive mechanical ventilation), acute renal and hematologic failure, following cesarean section. She required surgical reintervention for intra-abdominal bleeding due to coagulation disorders. During her hospital stay she required 50 platelet concentrates, 8 erythrocyte concentrates, 14 fresh plasmas and 4 platelet apheresis. After 14 days of hospital stay he was discharged due to clinical improvement. CONCLUSION: If no immediate action is taken, severe dengue is a cause of fatal mother-child outcome. The timely identification of the complications associated with this disease in pregnant women highlights the importance of prevention, early diagnosis and treatment. Similarly, it is important that in pregnant patients with this comorbidity, the obstetrics service should intervene in a timely manner in pre- and post-surgical surveillance.

7.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 39(2): 59-64, Febrero, 2021. tab, graf
Artículo en Español | IBECS | ID: ibc-208552

RESUMEN

Introducción: Haemophilus influenzae (Hi) causa infecciones leves e invasivas graves, especialmente en niños menores de 5 años. El serotipo b (Hib) era muy frecuente antes de la introducción de la vacuna, que en Paraguay se introdujo en 2004. Métodos: Se estudiaron por métodos microbiológicos convencionales y técnicas moleculares 523 aislados de H. influenzae obtenidos desde 1999 a 2017 y remitidos al Laboratorio Nacional de Referencia de Paraguay. Resultados: El serotipo más frecuente fue el no-tipable (HiNT), en un 51,8% (271/523), seguido de Hib (43%; 225/523), Hia e Hif (1,5%; 8/523, respectivamente), Hic (1%; 5/523), Hie (0,8%; 4/523) y Hid (0,4%; 2/523). El 48,4% de las infecciones invasivas estaban causadas por HiNT y el 46,1% por Hib. El 88,6% de las cepas procedían de casos de meningitis, el 70,8% de sepsis y el 50,9% de neumonías en niños menores de 5 años. El 84% (181/217) de las cepas correspondían a enfermedades invasivas causadas por Hib en menores de 5 años, registrándose la mayor proporción entre 2001-2003. Los biotipos más prevalentes fueron el biotipo I (29%), biotipo II (12%), biotipo III (24%) y biotipo IV (13%). El 13% (68/523) de los aislados fueron resistentes a la ampicilina. Conclusión: Tras de la introducción de la vacuna frente a Hib en Paraguay, los casos de enfermedad invasiva por Hib disminuyeron en niños menores de 5 años y hubo un aumento de HiNT en los mayores de 5 años. Es necesaria una vigilancia continua para monitorizar la eficacia de la vacuna y desarrollar intervenciones preventivas.(AU)


Introduction: Haemophilus influenzae is a cause of mild and severe invasive infections, especially among children under 5 years old. Serotype b (Hib) was very frequent before the introduction of the vaccine, which was introduced in Paraguay in 2004. Methods: A total of 523 isolates of H. influenzae obtained from 1999 to 2017 and referred to the National Reference Laboratory in Paraguay were studied by conventional microbiological methods and molecular techniques. Results: The most frequent serotype was non-typeable (HiNT) (51.8%; 271/523), followed by Hib (43%; 225/523), Hia and Hif (1.5%; 8/523, respectively), Hic (1%; 5/523), Hie (0.8%; 4/523), and Hid (0.4%; 2/523). A total of 48.4% invasive infections were caused by HiNT, and 46.1% by Hib; 88.6% of isolates corresponded to meningitis, 70.8% to sepsis and 50.9% to pneumonia in children under 5 years. A total of 84% (181/217) of isolates corresponded to invasive infections caused by Hib in children under 5 years, with the highest proportion observed between 2001 and 2003. The most prevalent biotypes were biotype I (29%), biotype II (12%), biotype III (24%), and biotype IV (13%). Among the total of isolates, 13% (68/523) of isolates were resistant to ampicillin. Conclusion: After the introduction of the Hib vaccine in Paraguay, the number of invasive Hib cases decreased in children under 5 years old, although we observed an increase of HiNT in children over 5 years. Continuous surveillance is necessary in order to monitor the effectiveness of the vaccine and for the development of preventive interventions.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Ciencias de la Salud , Haemophilus influenzae , Haemophilus influenzae tipo b , Vacunas Conjugadas , Infecciones por Haemophilus , Vacunas , Epidemiología Descriptiva , Paraguay/epidemiología , Enfermedades Transmisibles , Microbiología
8.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32197798

RESUMEN

INTRODUCTION: Haemophilus influenzae is a cause of mild and severe invasive infections, especially among children under 5 years old. Serotype b (Hib) was very frequent before the introduction of the vaccine, which was introduced in Paraguay in 2004. METHODS: A total of 523 isolates of H. influenzae obtained from 1999 to 2017 and referred to the National Reference Laboratory in Paraguay were studied by conventional microbiological methods and molecular techniques. RESULTS: The most frequent serotype was non-typeable (HiNT) (51.8%; 271/523), followed by Hib (43%; 225/523), Hia and Hif (1.5%; 8/523, respectively), Hic (1%; 5/523), Hie (0.8%; 4/523), and Hid (0.4%; 2/523). A total of 48.4% invasive infections were caused by HiNT, and 46.1% by Hib; 88.6% of isolates corresponded to meningitis, 70.8% to sepsis and 50.9% to pneumonia in children under 5 years. A total of 84% (181/217) of isolates corresponded to invasive infections caused by Hib in children under 5 years, with the highest proportion observed between 2001 and 2003. The most prevalent biotypes were biotype I (29%), biotype II (12%), biotype III (24%), and biotype IV (13%). Among the total of isolates, 13% (68/523) of isolates were resistant to ampicillin. CONCLUSION: After the introduction of the Hib vaccine in Paraguay, the number of invasive Hib cases decreased in children under 5 years old, although we observed an increase of HiNT in children over 5 years. Continuous surveillance is necessary in order to monitor the effectiveness of the vaccine and for the development of preventive interventions.


Asunto(s)
Infecciones por Haemophilus , Haemophilus influenzae , Niño , Preescolar , Estudios Epidemiológicos , Infecciones por Haemophilus/epidemiología , Humanos , Paraguay/epidemiología , Vacunas Conjugadas
9.
Artículo en Inglés, Español | MEDLINE | ID: mdl-32199673

RESUMEN

INTRODUCTION: The aim of this study was to describe the distribution of Streptococcus pneumoniae serotypes in isolates from pleural fluid in the Madrid Autonomous Community between the years 2007-2018. METHODS: Invasive pneumococcal disease strains isolated during the period 2007-2018 were studied. The frequency of serotypes from pleural fluid was compared with that observed in other samples. RESULTS: A total of 6,115 pneumococcal invasive isolates were processed. Of them, 182 (3%) were isolated from pleural fluid. A total of 70.9% of isolates belonged to some of the following 6serotypes: 1, 3, 19A, 8, 7F and 5. The serotypes 3 and 8 increased significantly from 9.6% to 30.8%, and from 5.3% to 20.5%, respectively, over the periods 2007-2010 to 2015-2018. CONCLUSIONS: Pneumococcal serotypes 3 and 8 are currently significant causes of infection of pleural fluid in our region.


Asunto(s)
Infecciones Neumocócicas , Streptococcus pneumoniae , Humanos , Infecciones Neumocócicas/epidemiología , Serogrupo
10.
Mem. Inst. Invest. Cienc. Salud (Impr.) ; 18(1)abr. 2020. ilus, tab
Artículo en Español | LILACS, BDNPAR | ID: biblio-1291903

RESUMEN

Streptococcus pneumoniae sigue siendo una de las causas más importantes de morbilidad y mortalidad en niños y adultos alrededor del mundo. El objetivo del estudio fue describir la frecuencia de aislamiento de S. pneumoniae en enfermedad invasiva, distribución de serotipos y sensibilidad antimicrobiana en Paraguay (2010-2018). Se estudiaron 793 cepas de S. pneumoniae aisladas de pacientes de todas las edades con enfermedad invasiva en Paraguay, provenientes de los diferentes centros centinelas y colaboradores en el marco de la vigilancia de meningitis y neumonías, durante el periodo 2010-2018. La frecuencia general según diagnóstico resultó 74.9% de neumonías (n=594), 18.4% de meningitis (n=146) y 6.7% de sepsis (n=53). El serotipo 14 fue más frecuente con 174 aislamientos (22.0%), seguido del serotipo 19A con 84 aislamientos (10.6%), el serotipo 3 con 66 aislamientos (8.3%) y el 6A con 37 aislamientos (4.7%). En meningitis se registró una frecuencia general de resistencia a penicilina del 32,2% y de ceftriaxona del 1,4%. En los casos de no meningitis la resistencia a penicilina fue del 0,8% y ceftriaxona del 0,3%. Los resultados de serotipos y sensibilidad antimicrobiana proporcionarán información necesaria para la implementación de estrategias de prevención y tratamiento de la enfermedad neumocócica en nuestro país, por lo que es necesaria una vigilancia continua para evaluar la carga de enfermedad, los serotipos circulantes y el aumento de la resistencia a los antibióticos


Streptococcus pneumoniae remains one of the most important causes of morbidity and mortality in children and adults worldwide. The objective of the study was to describe the frequency of isolation of S. pneumoniae in invasive disease, serotype distribution and antimicrobial susceptibility in Paraguay (2010-2018). We studied 793 strains of S. pneumoniae isolated from patients of all ages with invasive disease in Paraguay, from different sentinel centers and collaborators in the framework of meningitis and pneumonia surveillance during the period 2010-2018. The general frequency according to diagnosis was 74.9% of pneumonia (n = 594), 18.4% of meningitis (n = 146) and 6.7% of sepsis (n = 53). Serotype 14 was more frequent with 174 isolates (22.0%), followed by serotype 19A with 84 isolates (10.6%), serotype 3 with 66 isolates (8.3%) and 6A with 37 isolates (4.70%). In meningitis, there was a general frequency of penicillin resistance of 32.2% and ceftriaxone of 1.4%. In cases of non-meningitis, penicillin resistance was 0.8% and ceftriaxone 0.3%. The results of serotypes and antimicrobial sensitivity will provide necessary information for the implementation of prevention strategies and treatment of pneumococcal disease in our country, therefore it is necessary to continue monitoring in order to assess the burden of the disease, circulating serotypes and increased antibiotic resistance


Asunto(s)
Humanos , Masculino , Femenino , Neumonía Neumocócica , Streptococcus pneumoniae , Meningitis Neumocócica
11.
Enferm Infecc Microbiol Clin (Engl Ed) ; 38(8): 371-374, 2020 Oct.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31813642

RESUMEN

INTRODUCTION: To describe the distribution of Streptococcus pneumoniae serotypes isolated in cerebrospinal fluid (CSF) between 2007-2018 in the Community of Madrid (CM) and to identify those with higher meningeal tropism. METHODS: Strains isolated from invasive pneumococcal disease were sent to the Regional Laboratory of Public Health by Microbiology laboratories of public and private hospitals of the CM. The frequency of serotypes from CSF was compared with that observed in other samples. RESULTS: A total of 6,115 strains were processed and 5% (n=304) were isolated from CSF. Seven serotypes (11A, 19F, 23B, 10A, 24F, 23A and 35F) showed a frequency significantly higher in CSF than in other usually sterile samples. Serotypes 24F, 11A and 23B showed high penicillin-resistance. CONCLUSION: The frequency and resistance of certain pneumococcal serotypes with high meningeal tropism could compromise the treatment of central nervous system infections.


Asunto(s)
Meninges/microbiología , Meningitis Bacterianas , Infecciones Neumocócicas , Streptococcus pneumoniae , Humanos , Meningitis Bacterianas/líquido cefalorraquídeo , Meningitis Bacterianas/epidemiología , Meningitis Bacterianas/microbiología , Resistencia a las Penicilinas , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/microbiología , Serogrupo , España/epidemiología , Streptococcus pneumoniae/clasificación , Tropismo
12.
Ginecol. obstet. Méx ; 88(10): 659-666, ene. 2020. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1346146

RESUMEN

Resumen: OBJETIVO: Identificar los serotipos más frecuentes de virus del papiloma humano mediante pruebas al azar en pacientes previamente diagnosticadas con cáncer cervicouterino. MATERIALES Y MÉTODOS: Estudio prospectivo y observacional, efectuado en pacientes con displasia cervical, atendidas en el Hospital Regional Materno Infantil de Alta Especialidad de Nuevo León, Monterrey, entre enero y marzo de 2016. Criterios de inclusión: pacientes mayores de 18 años, que acudieron a la unidad médica para seguimiento y control ginecológico, con reporte anormal en la prueba de Papanicolaou, confirmado por histopatología, mediante biopsia dirigida por colposcopia. Criterios de exclusión: mujeres con histerectomía total por indicación de enfermedad benigna, sin antecedente de neoplasia intracervical; mayores a 70 años después de 3 citologías cervicales negativas en la década previa; pacientes que recibieron quimioterapia, radioterapia u otros tratamientos farmacológicos y quienes acudieron a revisión médica durante su ciclo menstrual. Para el análisis de los datos se utilizó estadística descriptiva. RESULTADOS: Se registraron 30 pacientes. Las clasificaciones más frecuentes de neoplasia cervical fueron: NIC-1 (n = 15), NIC-2 (n = 9) y NIC-3 (n = 6). Todas las pacientes analizadas tuvieron, al menos, un serotipo de VPH de alto riesgo. Los serotipos identificados con mayor frecuencia fueron el 31 y 33 (n = 18). En 18 pacientes se encontraron 6 o más serotipos de VPH. De 15 pacientes con lesiones de alto grado, 8 tuvieron la asociación de serotipos 31 y 33, y en 6 se identificó un serotipo aislado (16 y 51). CONCLUSIONES: Los serotipos identificados con mayor frecuencia fueron el 31 y 33. Desafortunadamente, la vacuna nonavalente que protege contra los serotipos más frecuentes de VPH no se encuentra disponible en Latinoamérica.


Abstract: OBJECTIVE: To identify the most frequent serotypes of human papillomavirus through random testing of patients previously diagnosed with cervical cancer. MATERIALS AND METHODS: A prospective, observational study carried out in patients with cervical dysplasia, treated at the High Specialty Regional Maternal and Child Hospital of Nuevo León, Monterrey. Inclusion criteria: patients over 18 years of age, who attended the Dysplasia Clinic of the High Specialty Regional Maternal and Child Hospital for gynecological follow-up and control, with an abnormal result in the Papanicolaou test, confirmed by histopathology, by means of colposcopy-directed biopsy. Before the procedures (cervical cytology), Exclusion criteria: women with total hysterectomy due to indications of benign disease, without a history of intracervical neoplasia; older than 70 years after 3 negative cervical cytology in the previous decade; patients who received chemotherapy, radiotherapy or other pharmacological treatments and who received medical check-ups during their menstrual cycle. Descriptive statistics were used for data analysis. RESULTS: 30 patients were registered. The most frequent classification of cervical neoplasia was: CIN1 (n = 15), CIN2 (n = 9) and CIN3 (n = 6). All the patients analyzed had at least one high-risk HPV serotype. The most frequently identified serotypes were 31 and 33 (n = 18 of 30). 6 or more HPV serotypes were found in 18 patients. Of 15 patients with high-grade lesions, 8 had the association of serotypes 31 and 33, and in 6 an isolated serotype was identified (16 and 51). CONCLUSIONS: The most frequently identified serotypes were 31 and 33. Unfortunately, the nonavalent vaccine that protects against the most frequent serotypes of HPV is not available in Latin America.

13.
Bol. méd. Hosp. Infant. Méx ; 76(6): 281-286, nov.-dic. 2019.
Artículo en Español | LILACS | ID: biblio-1089145

RESUMEN

Resumen Introducción: En México, cuando se inició la aplicación de la vacuna PCV13 (neumocócica conjugada), se cubría el 70.6% de los serotipos causantes de enfermedad invasiva por neumococo en menores de 5 años. Después de varios años, los casos de enfermedad causada por los serotipos incluidos en la vacuna han disminuido; sin embargo, se ha producido un reemplazo por los serotipos no incluidos en la vacuna. Caso clínico: Se presentan tres casos de pacientes pediátricos que desarrollaron enfermedad invasiva por serotipos no incluidos en la PCV13: uno con meningitis y bacteriemia (serotipo 15C) y dos con neumonía, uno de ellos complicado con derrame (serotipo 35B). Los pacientes fueron atendidos en un hospital pediátrico en Saltillo, Coahuila, durante el periodo de 2015 a 2018. Conclusiones: Resulta alarmante que se presenten tres casos graves por serotipos de Streptococcus pneumoniae no incluidos en la PCV13 en un solo hospital pediátrico en el norte del país. Este es un fenómeno que esta sucediendo a escala nacional e internacional: un incremento de casos de enfermedad invasiva por serotipos de neumococo no incluidos en la vacuna utilizada actualmente.


Abstract Background: In Mexico, 70.6% of serotypes causing invasive pneumococcal disease were covered since the application of the PCV13 vaccine in children under 5 years of age. After several years of immunization, cases of disease caused by the serotypes included in the vaccine have decreased. However, a replacement due to serotypes not included in the vaccine has been observed. Case report: Three cases of pediatric patients who developed invasive disease due to serotypes not included in PCV13 are described: one with meningitis and bacteremia (serotype 15C), and two with pneumonia, of which one complicated with effusion (serotype 35B). Patients were treated in a pediatric hospital in Saltillo, Coahuila, from 2015 to 2018. Conclusions: Three serious cases due to serotypes of Streptococcus pneumoniae not included in PCV13 were reported in a single pediatric hospital in a northern state of Mexico. This phenomenon is taking place nationwide and worldwide: an increase of cases of invasive disease due to pneumococcal serotypes not included in the vaccine currently used.


Asunto(s)
Preescolar , Femenino , Humanos , Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/clasificación , Vacunas Neumococicas , Infecciones Neumocócicas/complicaciones , Infecciones Neumocócicas/tratamiento farmacológico , Streptococcus pneumoniae/aislamiento & purificación , Serotipificación , Vacunas Conjugadas , México
14.
Bol Med Hosp Infant Mex ; 76(6): 281-286, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31769441

RESUMEN

Background: In Mexico, 70.6% of serotypes causing invasive pneumococcal disease were covered since the application of the PCV13 vaccine in children under 5 years of age. After several years of immunization, cases of disease caused by the serotypes included in the vaccine have decreased. However, a replacement due to serotypes not included in the vaccine has been observed. Case report: Three cases of pediatric patients who developed invasive disease due to serotypes not included in PCV13 are described: one with meningitis and bacteremia (serotype 15C), and two with pneumonia, of which one complicated with effusion (serotype 35B). Patients were treated in a pediatric hospital in Saltillo, Coahuila, from 2015 to 2018. Conclusions: Three serious cases due to serotypes of Streptococcus pneumoniae not included in PCV13 were reported in a single pediatric hospital in a northern state of Mexico. This phenomenon is taking place nationwide and worldwide an increase of cases of invasive disease due to pneumococcal serotypes not included in the vaccine currently used.


Introducción: En México, cuando se inició la aplicación de la vacuna PCV13 (neumocócica conjugada), se cubría el 70.6% de los serotipos causantes de enfermedad invasiva por neumococo en menores de 5 años. Después de varios años, los casos de enfermedad causada por los serotipos incluidos en la vacuna han disminuido; sin embargo, se ha producido un reemplazo por los serotipos no incluidos en la vacuna. Caso clínico: Se presentan tres casos de pacientes pediátricos que desarrollaron enfermedad invasiva por serotipos no incluidos en la PCV13: uno con meningitis y bacteriemia (serotipo 15C) y dos con neumonía, uno de ellos complicado con derrame (serotipo 35B). Los pacientes fueron atendidos en un hospital pediátrico en Saltillo, Coahuila, durante el periodo de 2015 a 2018. Conclusiones: Resulta alarmante que se presenten tres casos graves por serotipos de Streptococcus pneumoniae no incluidos en la PCV13 en un solo hospital pediátrico en el norte del país. Este es un fenómeno que esta sucediendo a escala nacional e internacional: un incremento de casos de enfermedad invasiva por serotipos de neumococo no incluidos en la vacuna utilizada actualmente.


Asunto(s)
Infecciones Neumocócicas/microbiología , Vacunas Neumococicas , Streptococcus pneumoniae/clasificación , Preescolar , Femenino , Humanos , México , Infecciones Neumocócicas/complicaciones , Infecciones Neumocócicas/tratamiento farmacológico , Serotipificación , Streptococcus pneumoniae/aislamiento & purificación , Vacunas Conjugadas
15.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29747999

RESUMEN

INTRODUCTION: Streptococcus pneumoniae (Sp) is the main cause of community-acquired pneumonia in the elderly, hence the importance to establish the prevalence of nasopharyngeal colonization by different Sp serotypes in adults. METHODS: from December 2009 to June 2010, nasopharyngeal cultures were taken from adults living in rural communities in Mexico for the isolation and serotyping of Sp by the Quellung reaction. Penicillin and ceftriaxone susceptibility tests were performed by the microdilution method. RESULTS: two hundred and thirty-six adults over 50 years old, were included. The prevalence of colonization by Sp was 21.6%. The most frequent serotypes were 19A (21%), 6A (13%), 6B and 11A (11%). All isolates were susceptible to ceftriaxone, and 52.8% of the isolates showed penicillin minimal inhibitory concentrations ≥0.12mg/L. CONCLUSION: this is the first study analyzing the nasopharyngeal colonization by Sp in adults in Mexico. Serotypes not included in any of the pneumococcal vaccines were frequently identified.


Asunto(s)
Portador Sano , Nasofaringe/microbiología , Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/clasificación , Estudios Transversales , Estudios Epidemiológicos , Femenino , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Resistencia a las Penicilinas , Infecciones Neumocócicas/epidemiología , Salud Rural , Serotipificación , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/aislamiento & purificación
16.
Rev. argent. microbiol ; 50(1): 12-22, mar. 2018. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-958025

RESUMEN

The objectives of this study were to determine the serovar of a collection of Actinobacillus pleuropneumoniae strains within the 3-6-8-15 cross-reacting group and to analyze their phenotypic and genetic properties. Based on the serological tests, forty-seven field strains of Actinobacillus pleuropneumoniae isolated from lungs with pleuropneumonia lesions in Japan and Argentina were found to be serovars belonging to the 3-6-8-15 cross-reacting group. By using a capsule loci-based PCR, twenty-nine (96.7%) and one (3.3%) from Japan were identified as serovars 15 and 8, respectively, whereas seventeen (100%) from Argentina were identified as serovar 8. The findings suggested that serovars 8 and 15 were prevalent within the 3-6-8-15 cross-reacting group, in Argentina and Japan, respectively. Phenotypic analyses revealed that the protein patterns observed on SDS-PAGE and the lipopolysaccharide antigen detected by immunoblotting of the reference and field strains of serovars 8 and 15 were similar to each other. Genetic (16S rDNA, apxIIA, apxIIIA, cps, cpx genes, apx and omlA patterns) analyses revealed that the apxIIA and apxIIIA genes of the field strains of serovars 8 and 15 were similar to those of the reference strains of serovars 3, 4, 6, 8 and 15. The results obtained in the present study may be useful for the development of more effective vaccines against disease caused by A. pleuropneumoniae by including the homologous antigens to the most prevalent serovars in specific geographical areas.


Los objetivos del presente estudio fueron determinar el serovar de una colección de cepas de Actinobacillus pleuropneumoniae pertenecientes al grupo 3, 6, 8, 15 de reacciones cruzadas y analizar sus propiedades fenotípicas y genéticas. En base a técnicas serológicas se determinó que cuarenta y siete cepas de A. pleuropneumoniae aisladas a partir de pulmones con lesiones de pleuroneumonía en Japón y Argentina pertenecen al grupo 3, 6, 8, 15. Mediante el uso de PCR basado en locus capsulares, veintinueve (96.7%) y una (3.3%) de los aislados japoneses fueron identificados como serovar 15 y 8 respectivamente, mientras que diecisiete (100%) de los aislados argentinos resultaron pertenecer al serotipo 8. Este hallazgo sugirió que los serovares 8 y 15 fueron los prevalentes dentro del grupo 3, 6, 8, 15 en Japón y Argentina, respectivamente. El análisis fenotípico reveló que los perfiles proteicos determinados por SDS-PAGE, y de antígenos lipopolisacáridos estudiados por inmunoblot, de las cepas de referencia y de campo de los serovares 8 y 15 fueron similares entre sí. El análisis genético (Í6S rDNA, apxIIA, apxIIA, cps, genes cpx, apx y los perfiles omlA) reveló que los genes apxIIA y apxIIIA de las cepas de campo de los serovares 8 y 15 fueron similares a sus homólogos de las cepas de referencia de los serovares 3, 4, 6, 8 y 15. Los resultados obtenidos en el presente estudio pueden ser útiles para el desarrollo de vacunas más efectivas contra la enfermedad causada por A. pleuropneumoniae, al posibilitar incluir antígenos homólogos a los serovares prevalentes en las áreas geográficas de interés.


Asunto(s)
Animales , Enfermedades de los Porcinos , Infecciones por Actinobacillus , Actinobacillus pleuropneumoniae , Argentina , Porcinos , Enfermedades de los Porcinos/genética , Infecciones por Actinobacillus/genética , Infecciones por Actinobacillus/veterinaria , Actinobacillus pleuropneumoniae/genética , Japón
17.
Enferm Infecc Microbiol Clin (Engl Ed) ; 36(8): 472-477, 2018 Oct.
Artículo en Inglés, Español | MEDLINE | ID: mdl-29029763

RESUMEN

INTRODUCTION: Streptococcus agalactiae, or group B streptococci (GBS), is the main aetiological agent of early neonatal sepsis in developed countries. This microorganism belongs to the gastrointestinal tract microbiota wherefrom it can colonize the vagina and be vertically transmitted to the child either before or at birth, and subsequently cause infection in the newborn. Approximately, 50% of newborns born to women with GBS become colonized, with 1-2% developing early neonatal infection if no preventive intervention is performed. The aim of this study was to characterize and compare serotypes, virulence factors and antimicrobial resistance of GBS isolates collected from pregnant women and newborns in several hospitals in Catalonia. METHODS: 242 GBS strains were analyzed including 95 colonizers and 68 pathogenic strains isolated from pregnant women, and 79 strains isolated from neonates with sepsis in order to determine serotype, virulence and antimicrobial resistance. RESULTS: Serotype distribution was different among the three groups, with serotypes Ia and II being significantly more frequent among colonizing strains (p=0.001 and 0.012, respectively). Virulence factors bca and scpB were significantly more frequent among neonatal strains than pathogenic or colonizing strains (p=0.0001 and 0.002, respectively). Pathogenic strains were significantly more resistant to erythromycin, clindamycin and azithromycin than their non-pathogenic counterparts. CONCLUSIONS: Taking into account that neonatal sepsis represents a significant problem on a global scale, epidemiological surveillance, antimicrobial resistance and GBS virulence at the local level could provide important knowledge about these microorganisms as well as help to improve treatment and prevent invasive infection caused by this microorganism.


Asunto(s)
Macrólidos/farmacología , Streptococcus agalactiae/efectos de los fármacos , Streptococcus agalactiae/patogenicidad , Farmacorresistencia Bacteriana , Femenino , Humanos , Recién Nacido , Embarazo , Serogrupo , España , Streptococcus agalactiae/clasificación , Streptococcus agalactiae/aislamiento & purificación , Virulencia
18.
Rev Argent Microbiol ; 50(1): 12-22, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28886933

RESUMEN

The objectives of this study were to determine the serovar of a collection of Actinobacillus pleuropneumoniae strains within the 3-6-8-15 cross-reacting group and to analyze their phenotypic and genetic properties. Based on the serological tests, forty-seven field strains of Actinobacillus pleuropneumoniae isolated from lungs with pleuropneumonia lesions in Japan and Argentina were found to be serovars belonging to the 3-6-8-15 cross-reacting group. By using a capsule loci-based PCR, twenty-nine (96.7%) and one (3.3%) from Japan were identified as serovars 15 and 8, respectively, whereas seventeen (100%) from Argentina were identified as serovar 8. The findings suggested that serovars 8 and 15 were prevalent within the 3-6-8-15 cross-reacting group, in Argentina and Japan, respectively. Phenotypic analyses revealed that the protein patterns observed on SDS-PAGE and the lipopolysaccharide antigen detected by immunoblotting of the reference and field strains of serovars 8 and 15 were similar to each other. Genetic (16S rDNA, apxIIA, apxIIIA, cps, cpx genes, apx and omlA patterns) analyses revealed that the apxIIA and apxIIIA genes of the field strains of serovars 8 and 15 were similar to those of the reference strains of serovars 3, 4, 6, 8 and 15. The results obtained in the present study may be useful for the development of more effective vaccines against disease caused by A. pleuropneumoniae by including the homologous antigens to the most prevalent serovars in specific geographical areas.


Asunto(s)
Infecciones por Actinobacillus , Actinobacillus pleuropneumoniae , Enfermedades de los Porcinos , Infecciones por Actinobacillus/genética , Infecciones por Actinobacillus/veterinaria , Actinobacillus pleuropneumoniae/genética , Animales , Argentina , Japón , Porcinos , Enfermedades de los Porcinos/genética
19.
Bol. Hosp. Viña del Mar ; 73(3): 97-98, sept. 2017.
Artículo en Español | LILACS | ID: biblio-948376

RESUMEN

La enfermedad neumocócica invasiva (ENI) es causa de morbimortalidad prevenible en pediatría. Con la introducción de vacunas antineumocócicas conjugadas disminuyó la prevalencia de ENI en 61,9% en los menores de 2 años, y se produjo un cambio en la distribución de serotipos y un aumento de ENI por serotipos no vaccinales. En este contexto, es relevante la vigilancia epidemiológica de los serotipos emergentes causantes de ENI en la población. Se presentará el caso de una lactante de 11 meses con diagnóstico de meningitis causada por neumococo serotipo 38, su evolución y consecuencias clínicas, y se realiza un análisis de la situación epidemiológica actual.


In pediatrics,invasive pneumococcal disease is a preventable cause ofmorbidity andmortality.The introduction of conjugated pneumococcal vaccines has reduced the prevalence of invasive pneumococcal disease by 61.9% in the under two's and has brought about a change in the distribution of serotypes and a rise in invasive pneumococcal disease caused by non-vaccine serotypes.This being the case,itis very importanttomonitorthe epidemiology ofthe emerging serotypes causing the disease in the population.We presentthe case of an 11 month old infant diagnosed with meningitis caused by serotype 38, describing his clinical course andclinical consequences; andweperforman analysis ofthepresent epidemiologica lsituation


Asunto(s)
Humanos , Femenino , Lactante , Infecciones Neumocócicas/diagnóstico , Infecciones Neumocócicas/microbiología , Infecciones Neumocócicas/terapia , Streptococcus pneumoniae/aislamiento & purificación , Serotipificación , Serogrupo
20.
Trop Med Int Health ; 22(9): 1154-1165, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28653334

RESUMEN

OBJECTIVE: To determine the susceptibility status of Aedes albopictus with and without Wolbachia to the four dengue virus serotypes. METHODS: Two newly colonised colonies of Ae. albopictus from the wild were used for the study. One colony was naturally infected with Wolbachia while in the other Wolbachia was removed by tetracycline treatment. Both colonies were orally infected with dengue virus-infected fresh blood meal. Dengue virus load was measured using quantitative RT-PCR at four-time intervals in the salivary glands, midguts and ovaries. RESULTS: Wolbachia did not significantly affect Malaysian Ae. albopictus dengue infection or the dissemination rate for all four dengue virus serotypes. Malaysian Ae. albopictus had the highest replication kinetics for DENV-1 and the highest salivary gland and midgut infection rate for DENV-4. CONCLUSION: Wolbachia, which naturally exists in Malaysian Ae. albopictus, does not significantly affect dengue virus replication. Malaysian Ae. albopictus is susceptible to dengue virus infections and capable of transmitting dengue virus, especially DENV-1 and DENV-4. Removal of Wolbachia from Malaysian Ae. albopictus would not reduce their susceptibility status.


Asunto(s)
Aedes , Virus del Dengue/patogenicidad , Dengue/transmisión , Insectos Vectores , Serogrupo , Replicación Viral , Wolbachia , Aedes/microbiología , Aedes/virología , Animales , Infecciones Bacterianas/complicaciones , Dengue/virología , Virus del Dengue/clasificación , Humanos , Reacción en Cadena de la Polimerasa
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