The direct effect of pneumococcal conjugate vaccines on invasive pneumococcal disease in children in the Latin American and Caribbean region (SIREVA 2006-17): a multicentre, retrospective observational study.

BACKGROUND: Streptococcus pneumoniae isolated from patients with invasive pneumococcal disease has been subjected to laboratory-based surveillance in Latin American and Caribbean countries since 1993. Invasive pneumococcal diseases remain a major cause of death and disability worldwide, particularly in children. We therefore aimed to assess the direct effect of pneumococcal conjugate vaccines (PCVs) on the distribution of pneumococcal serotypes causing invasive pneumococcal disease in children younger than 5 years before and after PCV introduction. METHODS: We did a multicentre, retrospective observational study in eight countries that had introduced PCV (ie, PCV countries) in the Latin American and Caribbean region: Argentina, Brazil, Chile, Colombia, Dominican Republic, Mexico, Paraguay, and Uruguay. Cuba and Venezuela were also included as non-PCV countries. Isolate data for Streptococcus pneumoniae were obtained between 2006 and 2017 from children younger than 5 years with an invasive pneumococcal disease from local laboratories or hospitals. Species' confirmation and capsular serotyping were done by the respective national reference laboratories. Databases from the Sistema Regional de Vacunas (SIREVA) participating countries were managed and cleaned in a unified database using Microsoft Excel 2016 and the program R (version 3.6.1). Analysis involved percentage change in vaccine serotypes between pre-PCV and post-PCV periods and the annual reporting rate of invasive pneumococcal diseases per 100 000 children younger than 5 years, which was used as a population reference to calculate percentage vaccine type reduction. FINDINGS: Between 2006 and 2017, 12 269 isolates of invasive pneumococcal disease were collected from children younger than 5 years in the ten Latin American and Caribbean countries. The ten serotypes included in ten-valent pneumococcal conjugate vaccine (PCV10) decreased significantly (p<0·0001) after any PCV introduction, except for the Dominican Republic. The percentage change for the ten vaccine serotypes in PCV10 countries was -91·6% in Brazil (530 [72·9%] of 727 before, 27 [6·1%] of 441 after); -85·0% in Chile (613 [72·6%] of 844 before, 44 [10·9%] of 404] after); -84·7% in Colombia (231 [63·1%] of 366 before, 34 [9·7%] of 352 after); and -73·8% in Paraguay (127 [77·0%] of 165 before, 22 [20·2%] of 109 after). In the 13-valent pneumococcal conjugate vaccine (PCV13) countries, the percentage change for the 13 vaccine serotypes was -59·6% in Argentina (853 [85·0%] of 1003 before, 149 [34·3%] of 434 after); -16·5% in the Dominican Republic (95 [80·5%] of 118 before, 39 [67·2%] of 58 after); -43·7% in Mexico (202 [73·2%] of 276 before, 63 [41·2%] of 153 after); and -45·9% in Uruguay (138 [80·7%] of 171 before, 38 [43·7%] of 87 after). Annual reporting rates showed a reduction from -82·5% (6·21 before vs 1·09 after per 100 000, 95% CI -61·6 to -92·0) to -94·7% (1·15 vs 0·06 per 100 000, -89·7 to -97·3) for PCV10 countries, and -58·8% (2·98 vs 1·23 per 100 000, -21·4 to -78·4) to -82·9% (7·80 vs 1·33 per 100 000, -76·9 to -87·4) for PCV13 countries. An increase in the amount of non-vaccine types was observed in the eight countries after PCV introduction together with an increase in their percentage in relation to total invasive strains in the post-PCV period. INTERPRETATION: SIREVA laboratory surveillance was able to confirm the effect of PCV vaccine on serotypes causing invasive pneumococcal disease in the eight PCV countries. Improved monitoring of the effect and trends in vaccine type as well as in non-vaccine type isolates is needed, as this information will be relevant for future decisions associated with new PCVs. FUNDING: None. TRANSLATIONS: For the Portuguese and Spanish translations of the abstract see Supplementary Materials section.

Estudio comparativo de la sensibilidad entre el cultivo y la reacción en cadena de la polimerasa para la detección de bordetella pertussis a partir de muestras de hisopado nasofaríngeo / Comparative study of culture and sensitivity polymerase chain reaction in the diagnosis of bordetella pertussis from nasopharyngeal swab specimens

La tosferina es una enfermedad infecciosa causada por Bordetella pertussis, que se diagnostica mediante el cultivo como técnica de referencia, la cual tiene como limitante una baja sensibilidad. Es debido a esto, que el presente trabajo se centró en evaluar a la técnica de PCR a punto final amplificando las secuencias IS481 y PT, como una metodología alternativa diagnóstica a partir de 100 muestras pareadas de hisopado nasofaríngeo de pacientes provenientes de distintas regiones de Venezuela. Dichas muestras pareadas constaron de un hisopado para realizar el cultivo bacteriano y el otro para la detección de ADN específico. La identificación microbiológica de B. pertussis incluyó el aislamiento del microorganismo en agar Regan-Lowe, identificación bioquímica y la confirmación por coaglutinación. El análisis de los resultados fue realizado empleando el programa SPSS 21.0.0., usando como herramienta estadística el test de McNemar. La sensibilidad obtenida por el protocolo de PCR a punto final fue 50%, en concordancia con reportes previos. De acuerdo al valor de p=0,002 obtenido, la detección de B. pertussis mediante los dos métodos presentó una diferencia para el diagnóstico de tosferina estadísticamente significativa, por lo que no es indiferente emplear ambas técnicas diagnósticas. Sin embargo, se recomienda emplear en forma combinada ambas metodologías para incrementar la probabilidad de realizar el diagnóstico.

Whooping cough is an infectious disease caused by Bordetella pertussis, diagnosed by culture as a reference technique, which has low sensitivity as limiting. It is because of this that the present work focused on evaluating the PCR technique endpoint amplifying IS481 and PT sequences, as an alternative methodology diagnostic from 100 paired samples of nasopharyngeal swabs from patients from different regions of Venezuela. Such paired samples comprised a swab for bacterial culture and the other for detection of specific DNA. Microbiological identification of B. pertussis included the isolation of the microorganism in agar Regan-Lowe, biochemical identification and confirmation by Coagglutination. The analysis of the results was performed using the SPSS program 21.0.0., as a statistical tool using the McNemar test. The sensitivity obtained by the PCR protocol endpoint was 50%, consistent with previous reports. According to the value of p = 0.002 obtained, detection of B. pertussis by the two methods showed a difference for the diagnosis of pertussis statistically significant, so it is not indifferent both diagnostic techniques employed. However, it is recommended to use both methods in combination to increase the likelihood of diagnosis.

PCR deduction of invasive and colonizing pneumococcal serotypes from Venezuela: a critical appraisal.

INTRODUCTION: Serotype surveillance of Streptococcus pneumoniae is indispensable for evaluating the potential impact of pneumococcal conjugate vaccines. Serotyping by the standard Quellung reaction is technically demanding, time consuming, and expensive. A simple and economical strategy is multiplex PCR-based serotyping. We evaluated the cost effectiveness of a modified serial multiplex PCR (mPCR), resolving 24 serotypes in four PCR reactions and optimally targeting the most prevalent invasive and colonizing pneumococcal serotypes found in Venezuela. METHODOLOGY: A total of 223 pneumococcal isolates, 140 invasive and 83 carriage isolates, previously serotyped by the Quellung reaction and representing the 18 most common serotypes/groups identified in Venezuela, were serotyped with the adapted mPCR. RESULTS: The mPCR serotyped 76% of all the strains in the first two PCR reactions and 91% after four reactions, correctly identifying 17 serotypes/groups. An isolate could be serotyped with mPCR in less than 2 minutes versus 15 minutes for the Quellung reaction, considerably lowering labor costs. A restrictive weakness of mPCR was found for the detection of 19F strains. Most Venezuelan 19F strains were not typeable using the mPCR, and two 19F cps serotype variants were identified. CONCLUSIONS: The mPCR assay is an accurate, rapid, and economical method for the identification of the vast majority of the serotypes from Venezuela and can be used in place of the standard Quellung reaction. An exception is the identification of serotype 19F. In this setting, most 19F strains were not detectable with mPCR, demonstrating a need of serology-based quality control for PCR-based serotyping.

Non-capsulated and capsulated Haemophilus influenzae in children with acute otitis media in Venezuela: a prospective epidemiological study.

BACKGROUND: Non-typeable Haemophilus influenzae (NTHi) and Streptococcus pneumoniae are major causes of bacterial acute otitis media (AOM). Data regarding AOM are limited in Latin America. This is the first active surveillance in a private setting in Venezuela to characterize the bacterial etiology of AOM in children < 5 years of age. METHODS: Between December 2008 and December 2009, 91 AOM episodes (including sporadic, recurrent and treatment failures) were studied in 87 children enrolled into a medical center in Caracas, Venezuela. Middle ear fluid samples were collected either by tympanocentesis or spontaneous otorrhea swab sampling method. Standard laboratory and microbiological techniques were used to identify bacteria and test for antimicrobial resistance. The results were interpreted according to Clinical Laboratory Standards Institute (CLSI) 2009 for non-meningitis isolates. All statistical analyses were performed using SAS 9.1 and Microsoft Excel (for graphical purposes). RESULTS: Overall, bacteria were cultured from 69.2% (63 of the 91 episodes); at least one pathogen (S. pneumoniae, H. influenzae, S. pyogenes or M. catarrhalis) was cultured from 65.9% (60/91) of episodes. H. influenzae (55.5%; 35/63 episodes) and S. pneumoniae (34.9%; 22/63 episodes) were the most frequently reported bacteria. Among H. influenzae isolates, 62.9% (22/35 episodes) were non-capsulated (NTHi) and 31.4% (11/35 episodes) were capsulated including types d, a, c and f, across all age groups. Low antibiotic resistance for H. influenzae was observed to amoxicillin/ampicillin (5.7%; 2/35 samples). NTHi was isolated in four of the six H. influenzae positive samples (66.7%) from recurrent episodes. CONCLUSIONS: We found H. influenzae and S. pneumoniae to be the main pathogens causing AOM in Venezuela. Pneumococcal conjugate vaccines with efficacy against these bacterial pathogens may have the potential to maximize protection against AOM.

Laboratory-based surveillance of Streptococcus pneumoniae invasive disease in children in 10 Latin American countries: a SIREVA II project, 2000-2005.

BACKGROUND: For the last 14 years the Pan American Health Organization has been promoting surveillance of invasive pneumococcal disease in Latin American children for better understanding of the disease tendencies regarding capsular types circulation in each country and susceptibility to antimicrobials. METHODS: Laboratory-based surveillance data from 10 Latin American countries collected from 2000 to 2005 were analyzed, including serotype distribution and susceptibility to beta-lactam antibiotics. RESULTS: Although 61 different capsular types were identified during the 6-year surveillance, 13 serotypes accounted for 86% of all isolates. These were consistently the most prevalent throughout the study period with serotype 14 predominating. Diminished susceptibility to penicillin was detected in 38% of all Streptococcus pneumoniae isolates, with the highest prevalence in Dominican Republic and Mexico. Decreased susceptibility to penicillin increased in Brazil and Colombia whereas decreased high resistance rates was recorded in Chile. CONCLUSIONS: These data indicate that 10 countries of the Region continue to have high quality laboratory-based surveillance for pneumococcal disease thus generating valuable information so that healthcare decision makers may prioritize interventions. The heptavalent vaccine will potentially cover from 52.4% to 76.5% of strains causing invasive pneumococcal disease and the 13 valent from 76.7% to 88.3%.

[Resistance to non-beta-lactam antibiotics in the clinical isolates of Streptococcus pneumoniae of children in Latin America. SIREVA II, 2000-2005]. / Resistencia a antibióticos no betalactámicos de aislamientos invasores de Streptococcus pneumoniae en niños latinoamericanos. SIREVA II, 2000-2005.

OBJECTIVE: To examine the development of resistance to erythromycin, chloramphenicol, trimethoprim-sulfamethoxazole (TMP-SMZ), and vancomycin of the invasive isolates of Streptococcus pneumoniae obtained from children in 10 Latin American/Caribbean countries during six years of surveillance. METHODS: Analysis of 8 993 isolates of S. pneumoniae recovered in 2000-2005 from children with invasive infections, who were less than 6 years of age, and from Argentina, Brazil, Chile, Colombia, Cuba, Dominican Republic, Mexico, Paraguay, Uruguay, or Venezuela. Antibiotic susceptibility was determined through the methods established and standardized by the SIREVA project. Multidrug resistance was defined as: resistance to three or more antibiotics of the same class; to the non-beta-lactams analyzed by this study; or, to the beta-lactams evaluated by a previous study, in which 37.8% of these isolates showed decreased susceptibility to penicillin. RESULTS: Some degree of resistance was found to TMP-SMZ and erythromycin (56.4% and 15.4% of the isolates studied, respectively), with 4.6% highly resistant to chloramphenicol. All isolates were susceptible to vancomycin. The highest prevalence of TMP-SMZ resistance was observed in the pneumonia isolates; and that of erythromycin, in cases of sepsis (61.6% and 25.5%, respectively; P < 0.01). The highest prevalence of TMP-SMZ resistance was found in Brazil (71.9%), and that of erythromycin, in Mexico (38.2%) and Venezuela (32.9%). The 14, 6B, 19F, and 23F serotypes were most often associated with resistance to the antibiotics in the study. CONCLUSIONS: High and increasing rates of isolates resistant to TMP-SMZ and erythromycin were observed, as well as a decreasing percentage of isolates resistant to chloramphenicol. These trends highlight differences among the countries studied.

Circulation of Streptococcus pneumoniae clone Colombia 5 ST289 in nine Latin American countries.

OBJECTIVE: To determine genetic relatedness of clone Colombia(5) ST289 with invasive Streptococcus pneumoniae serotype 5 isolates recovered in nine Latin American countries. METHODS: Forty-four invasive S. pneumoniae serotype 5 isolates recovered from children under 5 years of age in Bolivia, Chile, Dominican Republic, Ecuador, Nicaragua, Panama, Paraguay, Peru, and Venezuela were studied. Pulsed-field gel electrophoresis patterns of DNA treated with SmaI restriction enzyme were classified using Tenover's criteria and analyzed with the Fingerprinting II program to determine their genetic relatedness with the Colombian clone. RESULTS: All isolates had a genetic similarity of 78.5% or more with the Colombian clone. Thirteen electrophoretic subtypes derived of pattern A were identified, and five of them (A5, A6, A8, A13, A27) comprised 61.4% of the isolates. CONCLUSIONS: Clone Colombia(5) ST289 is disseminated in Latin America. This is important because S. pneumoniae serotype 5 frequently causes invasive disease in the region and is associated with trimethoprim-sulfamethoxazole resistance.

Circulation of Streptococcus pneumoniae clone Colombia5 ST289 in nine Latin American countries / Circulación de Streptococcus pneumoniae clon Colombia5 ST289 en nueve países de América Latina

OBJECTIVE: To determine genetic relatedness of clone Colombia5 ST289 with invasive Streptococcus pneumoniae serotype 5 isolates recovered in nine Latin American countries. METHODS: Forty-four invasive S. pneumoniae serotype 5 isolates recovered from children under 5 years of age in Bolivia, Chile, Dominican Republic, Ecuador, Nicaragua, Panama, Paraguay, Peru, and Venezuela were studied. Pulsed-field gel electrophoresis patterns of DNA treated with SmaI restriction enzyme were classified using Tenover's criteria and analyzed with the Fingerprinting II program to determine their genetic relatedness with the Colombian clone. RESULTS: All isolates had a genetic similarity of 78.5 percent or more with the Colombian clone. Thirteen electrophoretic subtypes derived of pattern A were identified, and five of them (A5, A6, A8, A13, A27) comprised 61.4 percent of the isolates. CONCLUSIONS: Clone Colombia5 ST289 is disseminated in Latin America. This is important because S. pneumoniae serotype 5 frequently causes invasive disease in the region and is associated with trimethoprim-sulfamethoxazole resistance.

OBJETIVO: Determinar la relación genética del clon Colombia5 ST289 con los aislamientos invasores de Streptococcus pneumoniae serotipo 5 provenientes de nueve países latinoamericanos. MÉTODOS: Se estudiaron 45 aislamientos invasores de Streptococcus pneumoniae serotipo 5 procedentes de niños menores de 5 años de Bolivia, Chile, Ecuador, Nicaragua, Panamá, Paraguay, Perú, República Dominicana y Venezuela. Los patrones en electroforesis en gel de campo pulsante del ADN tratado con la enzima de restricción SmaI se clasificaron mediante el criterio de Tenover y se analizaron con el programa Fingerprinting II para determinar su relación genética con el clon colombiano. RESULTADOS: Todos los aislamientos tuvieron una similitud genética de 78,5 por ciento o mayor con el clon colombiano. Se identificaron 13 subtipos electroforéticos derivados del patrón A y cinco de ellos (A5, A6, A8, A13 y A27) constituyeron 61,4 por ciento de los aislamientos. CONCLUSIONES: El clon Colombia5 ST289 está diseminado por América Latina. Esto es importante ya que S. pneumoniae serotipo 5 es causa frecuente de enfermedades invasoras en la Región y está asociado con la resistencia a trimetoprim-sulfametoxazol.

First isolation of a VIM-producing Klebsiella pneumoniae from a seven-year-old child in Venezuela.

BACKGROUND: VIM-type metallo-betalactamases (MBLs) exhibit hydrolytic activity against most betalactam antibiotics, including carbapenems. So far, VIM-type-producing Klebsiella pneumoniae isolates had not been reported in Latin America. METHODOLOGY: In July 2005, a carbapenem-resistant Klebsiella pneumoniae was isolated from a urine sample collected from a 7-year-old girl hospitalized at the Hospital de Niños "J. M. de los Ríos" in Caracas, Venezuela. This strain was identified using conventional biochemical tests. The susceptibility analysis was conducted by disk diffusion, and MICs for Imipenem and Meropenem were performed by agar dilution. For the phenotypic detection of MBL we used the Imipenem-EDTA/SMA double-disk diffusion method. The hydrolytic activity against carbapenems was determined by the Masuda microbiological method. Purified protein was subjected to isoelectric focusing (IEF). Detection of antimicrobial resistance genes was performed by PCR amplification with specific VIM primers. RESULTS: The strain showed resistance to most betalactam antibiotics, quinolones and amynoglicosides, but remained susceptible to Aztreonam and Cefepime. The use of phenotypic and microbiological methods detected the presence of a metallobetalactamase. By IEF we visualized three bands at pI 5.4, 7.6 and 7.9, corresponding to reduced-spectrum betalactamases, and a band at pI 5.8 that corresponded to the metallobetalactamase. PCR screening of bla genes revealed the presence of blaVIM, with an amplicon of 261 bp. CONCLUSIONS: This is the first report of a MBL-mediated carbapenem-resistant Klebsiella pneumoniae in Latin America, which constitutes a public health concern in our region since their transference to other microorganisms with multiple antibiotic resistance mechanisms will increase the antimicrobial resistance problem.

Resistencia a penicilina y cefalosporinas de tercera generación en cepas de Streptococcus pneumoniae / Resistance to penicillin and third generation cephalosporins in streptococcus pneumoniae strains

La Streptococcus pneumoniae continúa siendo la bacteria que ocasiona el mayor número de infecciones adquiridas en la comunidad. En la actualidad las cepas de Streptococcus pneumoniae pueden ser resistentes a múltiples drogas, siendo la prevalencia de neumococos resistentes a Penicilina elevada tanto en países desarrollados como subdesarrollados. Algunos de ellos pueden ser también resistentes a cefalosporinas de tercera generación. Determinar la prevalencia de cepas de neumococo resistentes a Penicilina y cefalosporinas de tercera generación productores de enfermedad invasiva en el Hospital de Niños "J. M. de los Ríos". Se detectó un 17,86% de Neumococos resistentes a Penicilina por Método de Kirby-Bauer. El 40% de las cepas estudiadas en el Instituto Nacional de Higiene por concentración inhibitoria mínima fueron resistentes a Penicilina, pero ninguna fue resistente a Cefalosporinas de tercera generación.

Vibrio cholerae O1 en Venezuela 1997-1999: sensibilidad a los antibióticos / Vidrio cholerae 01 in Venezuela 1997-1999: sensitivity of antibiotics

El presente estudio reporta los resultados de la vigilancia de la sensibilidad antibióticos en 202 cepas de V.cholerae O1 aisladas en Venezuela, desde enero de 1997 hasta diciembre de 1999. Se muestran los registros de las primeras cepas con resistencia a algunos antibióticos en Venezuela (12,2 por ciento), cefotaxima (15,4 por ciento), ceftriaxona (3,2 por ciento) y tetraciclina (0,6 por ciento), las cuales fueron aisladas en el brote detectado en el estado Zulia y que expandió por 14 entidades federales en 1997. También se demuestra el surgimiento de multiresistencia a los antibióticos en cepas aisladas en un segundo brote que inició en el estado Delta Amacuro y se extendió a los estados Sucre, Nueva Esparta, Monagas, Anzoátegui y Miranda. Los aislamientos resultaron resistentes a la ampicilina, ampicilina-sulbactam, co-trimoxazol y al agente vibriostático 0129, permaneciendo sensibles al ácido nalidíxico, cefotaxima, cetriaxona, ciprofloxacina, cloranfenicol, doxiciclina, gentamicina, norfloxacina, tetraciclina y tobramicina. Posteriores estudios deberán realizarse para determinar los mecanismos genéticos para la adquisición de esta resistencia a antibióticos.

Prevalencia de portadores nasales de staphylococos aureus en el personal médico del Hospital Militar Dr. Carlos Arvelo / Prevalency of carrier nasal of staphylococos aureous in the personnel physician of the Hospital Militar Dr. Carlos Arvelo

Entre noviembre de 1998 y mayo de 1999 se realizaron 50 hísopados nasales a médicos pertenecientes a servicios médicos (29 participantes) y servicios quirúrgicos (21). Se aisló Staphylococo coagulasa positivo (SCP) en 16 de ellos (32 por ciento). De estos aislados, el 81,5 por ciento fueron oxacilino sensibles el 18,5 por ciento fueron cepas oxacilino resistentes. Mupirocín tópico fue efectivo en erradicar el estado de portador de SCP en el 100 por ciento de los casos con efectos adversos muy leves