Estimación de la Relación Costo-Efectividad de las Vacunas Neumocócicas Conjugadas Prevenar-13 y Synflorix®, Utilizadas en Los Programas de Vacunación de Población Infantil Mexicana.

OBJECTIVE: To estimate the cost effectiveness associated with the use of pneumococcal conjugated vaccines, Prevenar-13 and Synflorix®, in the Mexican pediatric population. METHODS: The cost-effectiveness ratio of instrumenting vaccination programs based upon the use of Prevenar-13 and Synflorix® in the Mexican pediatric population was estimated by using a Markov's simulation model. The robustness of the conclusions reached on cost-effectiveness for both vaccines was assayed through an univariate and probabilistic sensitivity analysis that included all of the parameters considered by the model. RESULTS: Synflorix® was dominant over Prevenar-13 in the cost-utility analysis; the former generated more quality-adjusted life years at a lower cost and with a lower incremental cost-utility ratio. Based on the cost-effective analysis, Prevenar-13 generated more life years gained but at a higher cost. The use of Prevenar-13 originated a higher incremental cost-effectiveness ratio and, therefore, it was not cost-effective as compared with Synflorix®. CONCLUSIONS: Even though the simulations for Prevenar-13 and Synflorix® revealed both of them to be cost-effective when used to instrument pediatric vaccination campaigns in Mexico, Synflorix® had a better cost-utility/effectiveness profile. In addition, although Prevenar-13 and Synflorix® produced equivalent health outcomes, the overall analysis predicted that Synflorix® would save 360 million Mexican pesos, as compared with Prevenar-13.

Rhinovirus is an important pathogen in upper and lower respiratory tract infections in Mexican children.

BACKGROUND: Most of the studies characterizing the incidence of rhinovirus (RV) have been carried out in hospitalized children and in developed countries. In those studies, RV-C has been associated with more severe respiratory tract infections than RV species A and B. In this study we determined the frequency and diversity of RV strains associated with upper and lower respiratory tract infections (URTI, LRTI) in Mexico, and describe the clinical characteristics of the illness associated with different RV species. METHODS: A prospective surveillance of 526 and 250 children with URTI and LRTI was carried out. Respiratory samples were analyzed by RT-PCR for viruses. The 5' untranslated region of the RV genome was amplified and sequenced. RESULTS: In the case of URTI, 17.5% were positive for RV, while this virus was found in 24.8% of LRTI. The RV species was determined in 73 children with URTI: 61.6% were RV-A, 37% RV-C and, 1.4% RV-B; and in 43 children with LRTI: 51.2% were RV-A, 41.8% RV-C, and 7% RV-B. No significant differences in clinical characteristics were found in patients with RV-A or RV-C infections. A high genetic diversity of RV strains was found in both URTI and LRTI. CONCLUSIONS: Both RV-A and RV-C species were frequently found in hospitalized as well as in outpatient children. This study underlines the high prevalence and genetic diversity of RV strains in Mexico and the potential severity of disease associated with RV-A and RV-C infections.

Is there still room for novel viral pathogens in pediatric respiratory tract infections?

Viruses are the most frequent cause of respiratory disease in children. However, despite the advanced diagnostic methods currently in use, in 20 to 50% of respiratory samples a specific pathogen cannot be detected. In this work, we used a metagenomic approach and deep sequencing to examine respiratory samples from children with lower and upper respiratory tract infections that had been previously found negative for 6 bacteria and 15 respiratory viruses by PCR. Nasal washings from 25 children (out of 250) hospitalized with a diagnosis of pneumonia and nasopharyngeal swabs from 46 outpatient children (out of 526) were studied. DNA reads for at least one virus commonly associated to respiratory infections was found in 20 of 25 hospitalized patients, while reads for pathogenic respiratory bacteria were detected in the remaining 5 children. For outpatients, all the samples were pooled into 25 DNA libraries for sequencing. In this case, in 22 of the 25 sequenced libraries at least one respiratory virus was identified, while in all other, but one, pathogenic bacteria were detected. In both patient groups reads for respiratory syncytial virus, coronavirus-OC43, and rhinovirus were identified. In addition, viruses less frequently associated to respiratory infections were also found. Saffold virus was detected in outpatient but not in hospitalized children. Anellovirus, rotavirus, and astrovirus, as well as several animal and plant viruses were detected in both groups. No novel viruses were identified. Adding up the deep sequencing results to the PCR data, 79.2% of 250 hospitalized and 76.6% of 526 ambulatory patients were positive for viruses, and all other children, but one, had pathogenic respiratory bacteria identified. These results suggest that at least in the type of populations studied and with the sampling methods used the odds of finding novel, clinically relevant viruses, in pediatric respiratory infections are low.

SCCmec types and pvl gene in methicillin-resistant Staphylococcus aureus strains from children hospitalized in a tertiary care hospital in Mexico.

BACKGROUND: The aim of this study was to determine the prevalence, SCCmec types, presence of the Panton-Valentine leukocidin (PVL) gene, and susceptibility to antibiotics of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from hospitalized children. METHODS: From August 2009 to September 2011, 291 S. aureus strains were isolated from normally sterile body sites, of which 190 (65%) were MRSA. One hundred and two of the MRSA strains were genetically evaluated. SCCmec genotypes were identified by M-PCR and the PVL gene (pvl) by end-point PCR. Resistance to erythromycin, rifampicin, clindamycin, and trimethoprim-sulfamethoxazole (SXT) was assessed by Kirby-Bauer disk diffusion method in accordance with the Clinical and Laboratory Standards Institute guidelines of 2012. RESULTS: Of the 102 strains evaluated, 97 (95%) were SCCmec type II, 5 (5%) were SCCmec type IVa, and all (100%) were pvl-negative. Resistance to erythromycin, clindamycin, rifampicin, and SXT was 97%, 95%, 0%, and 0%, respectively. CONCLUSIONS: The prevalence of hospital-acquired MRSA was high. SCCmec type II was predominant and the pvl gene appeared not to play any role in the virulence of the MRSA strains from hospitalized children.

Infecciones respiratorias en niños migrantes indígenas de familias jornaleras mexicanas / Respiratory tract infections in indigenous migrant Mexican day-laboring families' children

Objetivo Identificar factores asociados a infecciones de vías respiratorias en niños migrantes indígenas de familias jornaleras del sector cañero en Colima, México. Métodos Estudio transversal descriptivo. Previo consentimiento informado, se entrevistaron 71 madres sobre aspectos sociodemográficos y antecedentes de infecciones de vías respiratorias en sus niños, durante el período decosecha 2010-2011. Se realizó antropometría a 176 niños de 0-14 años y se revisaron clínicamente en busca de infecciones de vías respiratorias superiores e inferiores. Se calcularon frecuencias, porcentajes, Ji cuadrado,razones de momios (cruda y ajustada) e intervalos de confianza del 95 %. Resultados El 52,3 % de los niños tuvieron antecedentes de infecciones respi-ratorias en los últimos seis meses. Los porcentajes de infecciones respiratorias tuvieron diferencias significativas por albergues de residencia. Los factores asociados al antecedente de infección fueronla edad menor a cuatro años (RMA=4,06, IC 95 % (2,03-8,09)) y la residencia temporal en un albergue conmayor hacinamiento en sus cuartos y mayor uso de fogones de leña para cocinar (RMA=1,92, IC95 % (1,01-3,63)). Conclusión Los niños migrantes indígenas de familias jornaleras son vulnerables a las infecciones de vías respiratorias. Los programas preventivos deben segmentar sus acciones por grupos de edad, con énfasis en los niños menores, y favorecer la mejora en las condiciones de salubridad en los albergues.(AU)

Objective Identifying factors associated with respiratory tract infection in indigenous migrant day-laborer families'children living inthe sugarcane sector in Colima, Mexico. Methods This was a cross-sectional study. Having given theirinformed consent, 71 mothers were interviewed for compiling pertinentsociodemographic data and a history of respiratory tract infection in their children during the harvest period 2010-2011. Anthropometry for 176 children aged 0-14 years was recorded and they were clinically examinedfor upper and lower respiratory tract infection. Frequencies, percentages, Chi-square, odds ratio (crude and adjusted) and 95 % confidence intervals were calculated for the resulting data. Results 52.3 % of the children in the sample had a history of respiratory infection occurring during the last six months. Respiratory infectionrates were statistically significant regarding temporary residence in shelters/hostels. The factors associated with a background of infection were being aged less than four years (AOR 4.06 (2.03-8.09) 95 % CI) and having been involved in temporary residence in a shelter,thereby leading tomore overcrowding and an increased use of wood stoves for cooking (AOR 1.92 (1.01-3.63) 95 % CI). ConclusionIndigenous migrant day-laboring families'children are vulnerable to respiratory infection. Prevention programs should target their activities by age-group, emphasizing younger children, and promote improved sanitary conditions in the shelters.(AU)

Sexual risk behavior and type of sexual partners in transnational indigenous migrant workers.

Indigenous migrant workers (IMWs) have a high vulnerability to HIV and STDs due to poverty and marginalization. This study examined factors associated with sexual risk behavior (SRB) according to type of partner in transnational young male IMWs at a sugar cane agro-industrial complex in western Mexico. A total of 192 sexually active IMWs were recruited from four laborer shelters to participate in a sexual partner survey. The IMWs were interviewed about their sexual partners and practices over the last 12 months during which it emerged that they had had a total of 360 sexual partners. Multiple linear regression analyses were performed to identify factors related to SRB in 222 main (spouse, mistress and girlfriend) and 138 casual partners (colleague, friend, casual encounter and sex worker). Results showed a significantly higher SRB score with casual partners. For the main partner regression model, prior exposure to HIV- and STD-preventive information and sexual intercourse with higher employment status partners (formal workers vs. self-employed in informal activities and unemployed) were associated with lower SRB scores, but if the sexual relations occurred in Mexico (vs. the U.S.), the SRB scores increased. For the casual partner model, the practice of survival sex (sex in exchange for basic needs), sexual relations in Mexico (vs. the U.S.), and being a circular migrant (person traveling for temporary work to return home when the contract is over) were related to higher SRB scores. Findings support the implementation of preventive interventions using different messages depending on the type of partners, main or casual, within the labor migrant context.

[Respiratory tract infections in indigenous migrant Mexican day-laboring families' children]. / Infecciones respiratorias en niños migrantes indígenas de familias jornaleras mexicanas.

OBJECTIVE: Identifying factors associated with respiratory tract infection in indigenous migrant day-laborer families'children living in the sugarcane sector in Colima, Mexico. METHODS: This was a cross-sectional study. Having given their informed consent, 71 mothers were interviewed for compiling pertinent sociodemographic data and a history of respiratory tract infection in their children during the harvest period 2010-2011. Anthropometry for 176 children aged 0-14 years was recorded and they were clinically examined for upper and lower respiratory tract infection. Frequencies, percentages, Chi-square, odds ratio (crude and adjusted) and 95 % confidence intervals were calculated for the resulting data. RESULTS: 52.3 % of the children in the sample had a history of respiratory infection occurring during the last six months. Respiratory infection rates were statistically significant regarding temporary residence in shelters/hostels. The factors associated with a background of infection were being aged less than four years (AOR 4.06 (2.03-8.09) 95 % CI) and having been involved in temporary residence in a shelter,thereby leading to more overcrowding and an increased use of wood stoves for cooking (AOR 1.92 (1.01-3.63) 95 % CI). CONCLUSION: Indigenous migrant day-laboring families'children are vulnerable to respiratory infection. Prevention programs should target their activities by age-group, emphasizing younger children, and promote improved sanitary conditions in the shelters.

Measurement of Haemophilus influenzae type a capsular polysaccharide antibodies in cord blood sera.

We measured anti-Haemophilus influenzae type a capsular polysaccharide serum immunoglobulin G antibodies in cord blood sera from Mexican (n = 68) and Chilean mothers (n = 72) by enzyme-linked immunosorbent assay. Measurable antibodies were found in 79.3% of samples. Immunoglobulin G antibodies correlated with serum bactericidal activity (r = 0.66). This enzyme-linked immunosorbent assay can be used for the evaluation of adaptive immune responses to Haemophilus influenzae type a and serosurveillance studies in populations at risk.

Phenotypes and genotypes of erythromycin-resistant Streptococcus pyogenes strains isolated from invasive and non-invasive infections from Mexico and the USA during 1999-2010.

OBJECTIVE: To compare the prevalence, phenotypes, and genes responsible for erythromycin resistance among Streptococcus pyogenes isolates from Mexico and the USA. METHODS: Eighty-nine invasive and 378 non-invasive isolates from Mexico, plus 148 invasive, 21 non-invasive, and five unclassified isolates from the USA were studied. Susceptibilities to penicillin, erythromycin, clindamycin, ceftriaxone, and vancomycin were evaluated according to Clinical and Laboratory Standards Institute (CLSI) standards. Phenotypes of erythromycin resistance were identified by triple disk test, and screening for mefA, ermTR, and ermB genes was carried out by PCR. RESULTS: All isolates were susceptible to penicillin, ceftriaxone, and vancomycin. Erythromycin resistance was found in 4.9% of Mexican strains and 5.2% of USA strains. Phenotypes in Mexican strains were 95% M and 5% cMLS; in strains from the USA, phenotypes were 33.3% iMLS, 33.3% iMLS-D, and 33.3% M. Erythromycin resistance genes in strains from Mexico were mefA (95%) and ermB (5%); USA strains harbored ermTR (56%), mefA (33%), and none (11%). In Mexico, all erythromycin-resistant strains were non-invasive, whereas 89% of strains from the USA were invasive. CONCLUSIONS: Erythromycin resistance continues to exist at low levels in both Mexico and the USA, although the genetic mechanisms responsible differ between the two nations. These genetic differences may be related to the invasive character of the S. pyogenes isolated.

[Consensus on the clinical and microbiologic diagnosis of Bordetella pertussis, and infection prevention. Expert Group on Pertussis Vaccination]. / Consenso para el diagnóstico clínico y microbiológico y la prevención de la infección por Bordetella pertussis. Grupo de expertos en vacunación contra tos ferina.

Pertussis continues to be responsible for a significant disease burden worldwide. Although immunization practices have reduced the occurrence of the disease among children, waning vaccine- and infection-induced immunity still allows the disease to affect adolescents and adults who, in turn, can transmit the disease to non-immunized or partially immunized infants. This document is the result of a meeting in Mexico City of international experts who analyzed recent medical information in order to establish the current status of the epidemiology, diagnosis and surveillance of pertussis and, especially, the value of the dTpa booster dose in adolescents and adults as a pertussis prevention strategy in Mexico.

Consenso para el diagnóstico clínico y microbiológico y la prevención de la infección por Bordetella pertussis / Consensus on the clinical and microbiologic diagnosis of Bordetella pertussis, and infection prevention

La tos ferina sigue siendo responsable de una carga de enfermedad importante en el mundo. Aunque la implementación del uso de la vacuna contra esta enfermedad ha disminuido en gran medida el número de casos en la población pediátrica, se ha observado que la inmunidad inducida por la vacuna y por la infeccion natural disminuye con el tiempo lo que hace nuevamente susceptibles a adolescentes y adultos jóvenes que pueden transmitir la enfermedad a lactantes no inmunizados o con esquema de vacunación incompleto. Este documento, resultado de la reunión de un grupo internacional de expertos en la Ciudad de México, ha analizado la información médica reciente para establecer el estado actual de la epidemiología, diagnóstico, vigilancia y, especialmente, el valor de la dosis de refuerzo con dTpa en adolescentes y adultos como estrategia de prevención de tos ferina en México.

Pertussis continues to be responsible for a significant disease burden worldwide. Although immunization practices have reduced the occurrence of the disease among children, waning vaccine- and infection-induced immunity still allows the disease to affect adolescents and adults who, in turn, can transmit the disease to non-immunized or partially immunized infants. This document is the result of a meeting in Mexico City of international experts who analyzed recent medical information in order to establish the current status of the epidemiology, diagnosis and surveillance of pertussis and, especially, the value of the dTpa booster dose in adolescents and adults as a pertussis prevention strategy in Mexico.

Clinical outcomes in Mexican children with febrile acute upper respiratory tract infections: no impact of antibiotic therapy.

OBJECTIVE: To compare the clinical outcomes (duration of signs and symptoms) and the microbiology in Mexican children with non-complicated febrile upper respiratory tract infections (URI), with and without the use of antibiotics. METHODS: We conducted a prospective cohort study from September 2006 to July 2007. The study population consisted of 880 children aged 6 months to 5 years 11 months, attending four community daycare centers run by the Instituto Mexicano del Seguro Social (IMSS) and three non-IMSS daycare centers. Children with a febrile URI were enrolled before receiving any antimicrobials and were followed up for two weeks. Duration of the fever, cough, runny nose, stuffy nose, irritability, loss of appetite, tiredness, and diarrhea, and isolation of Haemophilus influenzae,Streptococcus pneumoniae, and Streptococcus pyogenes were compared in those children who received antibiotic treatment and those who did not receive antibiotics. RESULTS: During the study period, a total of 145 out of 880 children were enrolled, and among those enrolled, 85/145 (59%) children received antibiotics. There was no significant difference in the duration of the signs and symptoms evaluated in the two groups. Although the proportions of S. pneumoniae, H. influenzae, and S. pyogenes isolated in children with and without antibiotics were comparable, those in whom we isolated S. pneumoniae had both a significantly longer episode of URI, as well as longer lasting diarrhea. Similarly, children receiving trimethoprim-sulfamethoxazole treatment experienced significantly longer durations of fever and diarrhea. CONCLUSIONS: The mean duration of signs and symptoms and the microbiological isolates of children with febrile URI were comparable among children treated with or without antibiotics, with the exception of a longer duration of URI and diarrhea in those children with an S. pneumoniae isolate. Our findings suggest that in our population, most cases of febrile URI are caused by viral infections, and demonstrate that antibiotics should not be used routinely in children with non-complicated febrile URI.

[Spread of S. pyogenes to the caretakers and relatives from nasopharyngeal carrier children attended in a day care center]. / Diseminación de S. pyogenes al personal y familiares de niños portadores nasofaríngeos de una guardería.

OBJECTIVE: to evaluate the prevalence of nasopharyngeal S. pyogenes (SP) carriers among children attending a day care center (DCC) and the spread of specific clones (SC) among caretakers and relatives. METHODS: nasopharyngeal cultures were performed in children with SP positive culture (306), family members (51) and caretakers (73) at time 0, and four and seven months later. Differences among SP strains were determined. Descriptive statistics and Fisher exact test were performed. RESULTS: SP prevalence in carrier children, caretakers and relatives was 10, 0 and 4 %. Three pairs of children, from two different classrooms, shared SP strains SC I, II and III. A clone VII was isolated from a relative. In the second survey, the SP prevalence was 4, 0 and 0 %. Two classmates shared clone I and other two from a different classroom shared clone V. In the third, the prevalence was 2, 4 and 14 %. Strains of clones II and VII were isolated from children. A sister of one child, who did not attend to DCC, was a carrier of clone II found in her brother. Clone III was isolated in one caretaker. CONCLUSIONS: the SP carrier prevalence was similar to other reports. The sharing of identical clones of SP was found among children in close physical contact.

[Risk factors associated to neonatal cross-infection]. / Factores de riesgo asociados a sepsis neonatal nosocomial.

BACKGROUND: Late-onset sepsis (occurring after 3 days of age) either cross-infection (CI) or perinatal is the first cause of morbidity and mortality in neonatal intensive care units (NICU) around the world. Our objective was to determine the current incidence of CI risk factors in neonates admitted to the NICU of the Hospital Civil de Guadalajara during a 9-month period. METHODS: A case-control study with 114 newborns; 38 with CI and 76 controls. Odds ratio with 95 % confidence interval were calculated. RESULTS: Associated risk factors were total parenteral nutrition (OR = 16.54, CI = 6.30-43.39, p < 0.001); weight < 1000 g (OR = 7.33, CI = 2.15-25.01, p < 0.001); intravascular catheter (OR = 6.79, CI = 2.68-17.00, p < 0.001); gestational age < 30 weeks (OR = 4.54, CI = 1.61-12.81, p < 0.003); intratracheal intubation and mechanical ventilation with (OR = 6.98, CI = 2.94-16.5, p < 0.001). CONCLUSIONS: Total parenteral nutrition and weight < 1000 g showed the greatest association with cross-infection; in this study, male gender was not a risk factor.

Parámetros clínicos y de laboratorio asociados a sepsis neonatal nosocomial / Clinical and laboratory parameters in neonatal nosocomial sepsis

Objetivo: Evaluar la utilidad de signos, síntomas y parámetros laboratoriales para predecir sepsis neonatal nosocomial. Métodos: De marzo de 2002 a junio de 2003 se identificaron 343 recién nacidos con sospecha de sepsis neonatal nosocomial, de los cuales 60 reunieron los criterios de inclusión. Se tomaron dos hemocultivos, biometría hemática, proteína C reactiva (PCR) seriada y un frotis de leucocitos teñidos con naranja de acridina o buffy coat. Los signos clínicos y laboratoriales fueron comparados en neonatos con y sin hemocultivo positivo, mediante χ2. Se calculó sensibilidad, especificidad, valores de predicción y razón de momios. Resultados: En 35/60 (58.3%) recién nacidos se aislaron bacterias patógenas. No se identificaron signos o síntomas asociados a sepsis neonatal nosocomial. Plaquetopenia (χ2=4.8 d.f. 1,p=0.03, RM=3.2, IC 95%=1.1-9.6); PCR positiva inicial (χ2=9.1 d.f. 1, p=0.003, RM=15.1, IC 95%=1.7-130.6) y buffy coat positivo (χ2=6.7 d.f.1,p=0.009, RM=11, IC 95%=1.3-91.9) se asociaron significativamente a sepsis neonatal nosocomial. Staphylococcus epidermidis y Serratia marcescens fueron las bacterias más aisladas. Conclusiones: Nuestros resultados fueron consistentes con otros informes, los signos y síntomas clínicos no son de utilidad para predecir sepsis neonatal nosocomial, mientras que la plaquetopenia, PCR y buffy coat positivos resultaron buenos predictores de esta patología.

OBJECTIVE: Assess if certain clinical and laboratorial data are associated with Neonatal Nosocomial Sepsis (NNS). METHODS: From March to June 2003, 343 premature neonates (PN) with clinical data suggestive of NNS were recruited; 60 fulfilled the inclusion criteria and were studied. Laboratory tests included two blood cultures from different peripheral veins, complete blood count (CBC), serial C reactive protein (CRP), and buffy coat (BC) smear stained with acridine orange. Clinical data and laboratory test results were compared among neonates with and without pathogenic bacteria isolated in the blood culture. Statistical analysis included chi-square tests (chi2), odds ratios (OR), sensitivity, specificity and predictive values. RESULTS: In 35/60 (58.3%) PN, a pathogenic bacteria was isolated in blood cultures. We did not identify signs and symptoms significantly associated with SNN. Thrombocytopenia (chi2 4.8 d.f. 1; p = 0.03; OR: 3.2, C.I. 95% 1.1-9.6); positive CRP (chi2 9.1 d.f. 1; p = 0.003; OR: 15.1 C.I. 95%. 1.7-130.6), and positive buffy coat smear (chi2 6.7 d.f. 1; p = 0.009; OR: 11 C.I. 95% 1.3-91.9) were associated with NNS. Staphylococcus epidermidis and Serratia marcescens were the most frequent isolated bacteria. CONCLUSIONS: The present study did not identify signs and symptoms associated with NNS. Nevertheless, thrombocytopenia, positive CRP and positive buffy coat smear were considered adequate predictive factors.

Serotypes and susceptibility of Streptococcus pneumoniae strains isolated from children in Mexico.

OBJECTIVE: To identify serotypes and susceptibility of S. pneumoniae strains from 48 children with invasive infections and 50 carriers. MATERIAL AND METHODS: Typing was performed by the Quellung reaction and susceptibility by Kirby-Bauer and Etest according to CLSI standards. RESULTS: Of 31 meningeal strains, serotypes 19F, 3, 6B, 14 and 23F were predominant. Resistance to penicillin and STX was 16 and 58%, respectively; of 17 invasive non-meningeal strains, serotypes 19F and 3 were predominant and resistance to penicillin and SXT was 0 and 82%, respectively; of carrier strains, serotypes 6A, 6B, 19F and 23F were predominant. CONCLUSIONS: A 10-valent conjugate vaccine could offer a better coverage for meningeal strains.

Serotypes and susceptibility of Streptococcus pneumoniae strains isolated from children in Mexico / Serotipos y susceptibilidad de cepas de Streptococcus pneumoniae aisladas de niños en México

Objective. To identify serotypes and susceptibility of S. pneumoniae strains from 48 children with invasive infections and 50 carriers. Material and Methods. Typing was performed by the Quellung reaction and susceptibility by Kirby-Bauer and Etest according to CLSI standards. Results. Of 31 meningeal strains, serotypes 19F, 3, 6B, 14 and 23F were predominant. Resistance to penicillin and STX was 16 and 58 percent, respectively; of 17 invasive non-meningeal strains, serotypes 19F and 3 were predominant and resistance to penicillin and SXT was 0 and 82 percent, respectively; of carrier strains, serotypes 6A, 6B, 19F and 23F were predominant. Conclusions. A 10-valent conjugate vaccine could offer a better coverage for meningeal strains.

Objetivo. Identificar serotipos y susceptibilidad en cepas aisladas de 48 niños con infecciones invasivas y de 50 portadores. Material y métodos. Serotipificación mediante reacción de Quellung y susceptibilidad mediante Kirby-Bauer y E-test. Resultados. De 31 cepas meníngeas, predominaron serotipos 19F, 3, 6B, 14 y 23F y la resistencia a penicilina (P) y trimetoprim-sulfametoxazol (SXT) fue de 16 y 58 por ciento. En 17 cepas invasivas no meníngeas, predominaron serotipos 19F y 3 y la resistencia a P y SXT fue de 0 y 82 por ciento, en cada caso. En portadores predominaron serotipos 6A, 6B, 19F y 23F. Conclusiones. La resistencia es similar a otros informes. La vacuna conjugada 10-valente podría ofrecer mejor cobertura para serotipos asociados a meningitis.