Estrategia regulatoria del desarrollo de Quimi-Hib®, vacuna conjugada semisintética contra Haemophilus influenzae tipo b

Introducción: Quimi-Hib®, una vacuna cubana obtenida por síntesis química y única en el mundo, requirió una estrategia regulatoria específica, porque no hay guía con las pautas requeridas para su producción y control. Objetivo: Caracterizar la estrategia regulatoria de la etapa precomercialización de Quimi-Hib® en Cuba. Material y Métodos: Estudio descriptivo-retrospectivo de requisitos para el registro sanitario de la vacuna cubana. Se establecieron siete pasos estratégicos para abarcar los estándares reguladores vigentes y futuros, con base en opiniones de expertos para la adopción de decisiones. El punto de partida fue la guía de la OMS, aplicable a vacunas anti-Hib de origen natural. Resultados: La estrategia regulatoria se desarrolló a partir de las 15 recomendaciones de esta guía, 11 de ellas se extrapolaron a la vacuna cubana y cuatro no, pero se consideraron sus fundamentos para desarrollar cuatro requerimientos aplicables a la vacuna semisintética. Se adicionaron otros seis, tres a solicitud de la Autoridad Reguladora Nacional de Cuba y tres obtenidos de la literatura relevante disponible. Estos 21 requerimientos completan el paquete regulador, resultado de la estrategia desarrollada para esta vacuna y la posterior aprobación de su registro sanitario y comercialización. Conclusiones: La estrategia regulatoria desarrollada en este trabajo permitió definir un conjunto de recomendaciones que suple la carencia de regulaciones internacionales y contribuyó a la obtención segura del registro sanitario de la vacuna Quim-Hib® que podría generalizarse a otras vacunas con características similares.

Introduction: Quimi-Hib®, a Cuban vaccine obtained by chemical synthesis and unique in the world, required its own regulatory strategy because there is no guideline on the requirements for its production and control. Objective: To characterize the regulatory strategy of the pre-launch phase of Quimi-Hib® in Cuba. Material and Methods: Descriptive-retrospective study of the requirements for the approval of the Cuban vaccine. Seven strategic steps were established to cover current and future regulatory standards based on expert advice for decision making. The starting point was the WHO´s guideline, which applies to anti-Hib vaccines of natural origin. Results: The regulatory strategy was developed based on the 15 recommendations of the aforementioned guideline, 11 of which were extrapolated to the Cuban vaccine and four of which were not, but served as the basis for the development of four requirements with similar rationale that apply to the semisynthetic vaccine. Six additional requirements were added, three of which were requested from the Cuba's National Regulatory Authority and three of which were obtained from the available relevant literature. These 21 requirements complete the regulatory package, the result of the strategy developed for this vaccine and the subsequent approval for marketing authorization and commercialization. Conclusions: The regulatory strategy compensates for the lack of specific guidelines for synthetic Haemophilus influenzae type b vaccines and thus contributed to the approval of the first vaccine of this type. The regulatory strategy is flexible because it includes update requirements throughout the vaccine life cycle, and expert consensus was considered in its development.

Pediatric bacterial meningitis and meningococcal disease profile in a Brazilian General Hospital

Abstract Objective To evaluate the clinical and epidemiological profile of bacterial meningitis and meningococcal disease in pediatric patients admitted to a Brazilian Secondary Public Hospital. Methods A descriptive observational study was conducted. Microbiologically proven bacterial meningitis or meningococcal disease diagnosed from 2008 to 2018 were included. Results A total of 90 patients were diagnosed with proven bacterial meningitis. There were 64 confirmed cases of meningococcal disease. The prevalence was higher in boys (n=38), median age 30 months (1-185). The main clinical manifestations were: meningococcal meningitis (n=27), meningococcemia without meningitis (n=14), association of meningococcemia with meningitis (n=13), and fever without a known source in infants (n=7).Admissions to intensive care unit were necessary for 45 patients. Three deaths were notified. Serogroup C was the most prevalent (n=32) followed by serogroup B (n=12).Pneumococcal meningitis was identified in 21 cases; out of the total, 10 were younger than two years. The identified serotypes were: 18C, 6B, 15A, 28, 7F, 12F, 15C, 19A and 14. Pneumococcal conjugate 10-valent vaccine covered four of the nine identified serotypes.Haemophilus influenzae meningitis serotype IIa was identified in three patients, median age 4 months (4-7). All of them needed intensive care. No deaths were notified. Conclusion Morbidity and mortality rates from bacterial meningitis and meningococcal disease remain high, requiring hospitalization and leading to sequelae. Our study observed a reduced incidence of bacterial disease over the last decade, possibly reflecting the impact of vaccination.

Vaccination herd effect experience in Latin America: a systematic literature review.

BACKGROUND: National pediatric vaccination programs have been introduced in Latin America (LatAm) to reduce the burden of diseases due to pathogens such as rotavirus, Haemophilus influenzae type b (Hib) and pneumococcus. Vaccination health benefits may extend to unvaccinated populations by reducing pathogen transmission. Understanding herd effect is important for implementation and assessment of vaccination programs. The objective was to conduct a systematic review of published epidemiological evidence of herd effect with Hib, rotavirus and pneumococcal conjugate vaccines (PCV) in LatAm. METHODS: Searches were conducted in PubMed, Virtual Health Library (VHL), SciELO and SCOPUS databases, for studies reporting data on herd effect from Hib, rotavirus and PCV vaccination in LatAm, without age restriction. Searches were limited to articles published in English, Spanish or Portuguese (1990-2016). After screening and full-text review, articles meeting the selection criteria were included to be critically appraised following criteria for observational and interventional studies. The presence of a herd effect was defined as a significant decrease in incidence of disease, hospitalization, or mortality. RESULTS: 3,465 unique articles were identified, and 23 were included (Hib vaccine n = 5, PCV n = 8, rotavirus vaccine n = 10). Most studies included children and/or adolescents (age range varied between studies). Studies in adults, including older adults (aged > 65 years), were limited. Few studies reported statistically significant reductions in disease incidence in age groups not targeted for vaccination. Hib-confirmed meningitis hospitalization decreased in children but herd effect could not be quantified. Some evidence of herd effect was identified for PCV and rotavirus vaccine in unvaccinated children. Evidence for herd effects due to PCV in adults was limited. CONCLUSION: After introduction of Hib, PCV and rotavirus vaccination in LatAm, reductions in morbidity/mortality have been reported in children not targeted for vaccination. However, due to methodological limitations (e.g. short post-vaccination periods and age range studied), there is currently insufficient evidence to quantify the herd effect in adult populations. More research and higher quality surveillance is needed to characterize herd effect of these vaccines in LatAm.

Episodio Hipotonía-Hiporreactividad posterior a la inmunización con vacuna combinada con pertussis de células enteras. Reporte de un caso / Hypotonic-Hyporesponsive Episode after immunization with whole-cell pertussis combination vaccine. Clinical Case Report

Resumen Introducción: El Episodio Hipotonía-Hiporreactividad (EHH) es un efecto adverso tras la vacuna ción, asociado principalmente a vacunas anti-pertussis de células enteras. Se caracteriza por un inicio súbito de flacidez muscular, reducida respuesta a estímulos y palidez cutánea o cianosis. Aunque el EHH es infrecuente, está considerado como un efecto adverso severo. Objetivo: Reportar un caso de EHH posterior a la administración de la vacuna combinada pentavalente con: difteria, tétanos, pertussis celular, hepatitis B y Haemophilus influenzae tipo b (DTwP-HB-Hib), que está incluida en el Programa Nacional de Inmunizaciones (PNI) de Chile, con la finalidad de difundir esta infrecuente complicación de evolución benigna, auto-limitada y de carácter no recurrente. Caso clínico: Lactante de 6 meses de edad, 3 h post-vacunación con la tercera dosis de vacuna DTwP-HB-Hib, presentó compromiso del estado de conciencia interpretado como convulsión atónica y que finalmente se consideró como EHH. El lactante evolucionó favorablemente después de 2 h y fue dado de alta tras 24 h de vigilancia clínica; se cambió el esquema de inmunización del lactante con vacunas anti-per tussis acelulares como medida preventiva. Conclusiones: El desconocimiento sobre el EHH puede desalentar la inmunización infantil. Por lo tanto, es importante que el personal médico informe a los padres de los pacientes sobre este evento benigno, autolimitado y no recurrente. En estos casos, se re comienda continuar con el programa de inmunización del lactante con formulaciones que contengan componentes anti-pertussis acelulares.

Abstract Introduction: Hypotonic-Hyporesponsive Episode (HHE) is an adverse event after vaccination, mainly associated with whole-cell pertussis vaccines. It is characterized by a sudden onset of muscle flaccidity, reduced response to stimuli and pallor or cyanosis. Although the HHE is infrequent, it is considered a severe adverse event. Objective: To report a case of HHE following the administration of the whole-cell pertussis combination vaccine (DTwP-HB-Hib), which is included in National Im munization Program (PNI) of Chile, and to contributing to the knowledge of this adverse event in the country. Case report: A 6-month-old infant, 3 hours post-vaccination with the third dose of DTwP-HB-Hib vaccine, presented a decreased level of consciousness that was interpreted as atonic seizure but finally considered as EHH. The infant progressed favorably after 2 hours of clinical observation and was discharged 24 hours later. Parents were suggested to continue the immunization schedule of the infant with acellular pertussis vaccines as a preventive measure. Conclusions: The lack of knowledge about the EHH may discourage childhood immunization. Therefore, it is important for the medical staff to inform parents of the patients about this benign, self-limited and non-recurrent adverse event. In these cases, it is recommended to continue the immunization schedule of the infant with acellular pertussis vaccines.

Experimental design and metabolic flux analysis tools to optimize industrially relevant Haemophilus influenzae type b growth medium.

Haemophilus influenzae type b (Hib), a Gram-negative capsulated bacterium, is a causative agent of meningitis worldwide. The capsular polysaccharide, a high molecular mass polymer consisting of the repeated units of the polyribosyl-ribitol-phosphate, is considered the main virulence factor and it is used as an antigen to vaccines, conjugated to a carrier protein. The industrial production of the polysaccharide requires the cultivation of Hib in rich medium, which impacts process costs and product recovery. In this study, a central composite rotational experimental design strategy was used to access the influence of key components of culture medium (soy peptone, yeast extract and glucose) on biomass formation and polysaccharide production in shake-flasks. The optimized medium formulation, containing half of the usual yeast extract and soytone concentrations, was further validated in batch bioreactor cultivations. High polysaccharide production (∼500 mg/L) was obtained in a cheaper and more competitive production process for use in Hib vaccine production. In addition, simulations of a metabolic model describing Hib central metabolism were used to assess the role of key amino acids on growth. A chemically defined medium supplemented only with amino acids from α-ketoglutarate and oxaloacetate families as well as phenylalanine was suggested as a promising alternative for reduced acetate accumulation and enhanced polysaccharide production in Hib cultures. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1508-1519, 2017.

Evaluation of Haemophilus influenzae type b carrier status among children 10 years after the introduction of Hib vaccine in Brazil

The aim of the present study was to assess the prevalence of Haemophilus influenzaetype b (Hib) nasopharyngeal (NP) colonisation among healthy children where Hib vaccination using a 3p+0 dosing schedule has been routinely administered for 10 years with sustained coverage (> 90%). NP swabs were collected from 2,558 children who had received the Hib vaccine, of whom 1,379 were 12-< 24 months (m) old and 1,179 were 48-< 60 m old. Hi strains were identified by molecular methods. Hi carriage prevalence was 45.1% (1,153/2,558) and the prevalence in the 12-< 24 m and 48-< 60 m age groups were 37.5% (517/1,379) and 53.9% (636/1,179), respectively. Hib was identified in 0.6% (16/2,558) of all children in the study, being 0.8% (11/1,379) and 0.4% (5/1,179) among the 12-< 24 m and 48-< 60 m age groups, respectively. The nonencapsulate Hi colonisation was 43% (n = 1,099) and was significantly more frequent at 48-< 60 m of age (51.6%, n = 608) compared with that at 12-< 24 m of age (35.6%, n = 491). The overall resistance rates to ampicillin and chloramphenicol were 16.5% and 3.7%, respectively; the co-resistance was detected in 2.6%. Our findings showed that the Hib carrier rate in healthy children under five years was very low after 10 years of the introduction of the Hib vaccine.

Safety of a quadrivalent meningococcal serogroups A, C, W and Y conjugate vaccine (MenACWY-CRM) administered with routine infant vaccinations: results of an open-label, randomized, phase 3b controlled study in healthy infants.

BACKGROUND: The highest risk for invasive meningococcal disease (IMD) is in infants aged <1 year. Quadrivalent meningococcal conjugate vaccination has the potential to prevent IMD caused by serogroups A, C, W and Y. This phase 3b, multinational, open-label, randomized, parallel-group, multicenter study evaluated the safety of a 4-dose series of MenACWY-CRM, a quadrivalent meningococcal conjugate vaccine, concomitantly administered with routine vaccinations to healthy infants. METHODS: Two-month-old infants were randomized 3:1 to receive MenACWY-CRM with routine vaccines or routine vaccines alone at ages 2, 4, 6 and 12 months. Adverse events (AEs) that were medically attended and serious adverse events (SAEs) were collected from all subjects from enrollment through 18 months of age. In a subset, detailed safety data (local and systemic solicited reactions and all AEs) were collected for 7 days post vaccination. The primary objective was a non-inferiority comparison of the percentages of subjects with ≥1 severe systemic reaction during Days 1-7 after any vaccination of MenACWY-CRM plus routine vaccinations versus routine vaccinations alone (criterion: upper limit of 95% confidence interval [CI] of group difference <6%). RESULTS: A total of 7744 subjects were randomized with 1898 in the detailed safety arm. The percentage of subjects with severe systemic reactions was 16% after MenACWY-CRM plus routine vaccines and 13% after routine vaccines alone (group difference 3.0% (95% CI -0.8, 6.4%). Although the non-inferiority criterion was not met, post hoc analysis controlling for significant center and group-by-center differences revealed that MenACWY-CRM plus routine vaccinations was non-inferior to routine vaccinations alone (group difference -0.1% [95% CI -4.9%, 4.7%]). Rates of solicited AEs, medically attended AEs, and SAEs were similar across groups. CONCLUSION: In a large multinational safety study, a 4-dose series of MenACWY-CRM concomitantly administered with routine vaccines was clinically acceptable with a similar safety profile to routine vaccines given alone.

Post-authorization safety surveillance of a liquid pentavalent vaccine in Guatemalan children.

OBJECTIVE: Combination vaccines have improved the efficiency of delivery of new vaccines in low and middle-income countries. Post-authorization monitoring of adverse events (AEs) after vaccination with a liquid pentavalent DTwP-HepB-Hib combination vaccine was conducted in Guatemalan infants. METHODS: A prospective observational safety study of the incidence of medical attended events (MAEs) and serious adverse events (SAEs) in children who received pentavalent and oral polio vaccines at 2, 4 and 6 months of age was conducted in two clinics at the Institute of Guatemala. Parents were contacted by telephone after each dose. All outpatient, emergency department visits, and hospitalizations were monitored. A self-controlled analysis was conducted to determine if there was evidence of increased risk of MAEs or SAEs following vaccines as compared to control time windows. RESULTS: Of 3000 recruited infants, 2812 (93.7%) completed the third dose and 2805 (93.5%) completed follow-up. Ten AEs in eight infants, of which four SAEs in four infants, were classified as related to the vaccine. Thirteen deaths were reported due to common illnesses of infancy, and none were judged to be related to the vaccine. The mortality rate (4.4 per 1000) was lower than expected for the population. The incidence-rate-ratio for healthcare visits was lower in post-vaccination time windows than for control windows; after the first vaccine dose, the rate ratios for the risk periods of 0-1, 2-6, and 7-30 days post-vaccination were 0.3, 0.5, and 0.7, respectively (all statistically significantly different from the reference value of 1.0 for the 31-60 day control period). CONCLUSION: The liquid pentavalent vaccine was associated with lower rates of health care visits and not associated with increases in SAEs or hospitalizations. Systems can be set up in low to middle income countries to capture all health care visits to monitor the safety of new vaccines.

A situação vacinal das crianças que apresentaram eventos adversos com vacina tetravalente no município de Belém-PA, 2008 / The immunization status of children experiencing adverse events with tetravalent vaccine in Belem, PA, 2008

Alguns estudos que tem acompanhado a utilização da vacina tetravalente na rotina do PNI desde 2002 observaram uma incidência maior de eventos adversos associados à mesma em comparação com as demais vacinas do calendário vacinal. Este estudo teve como objetivo conhecer a situação vacinal das crianças que apresentaram eventos adversos após vacinação de tetravalente na rede pública do município de Belém no ano de 2008. Foi realizado um estudo transversal. A população estudada foi a de menores de um ano que apresentaram eventos adversos após vacinação tetravalente. Foram analisadas variáveis relacionadas às características sócio-econômicas dos responsáveis, à situação vacinal das crianças participantes e aos eventos adversos após a vacina. Verificou-se que 33,3 por cento das crianças participantes apresentaram algum atraso no esquema vacinal, e os principais motivos do atraso foram o esquecimento por parte da mãe (22,8por cento) e a falta de orientação dos profissionais de saúde (13,7 por cento). Concluiu-se que tais motivos podem indicar falhas na atenção primária em saúde no que se refere ao controle de doenças que, atualmente, são preveníveis por vacinação, assim, presume-se que tenham ocorrido oportunidades perdidas de vacinar estas crianças.

Pattern of functional antibody activity against Haemophilus influenzae type b (Hib) in infants immunized with diphtheria-tetanus-pertussis/Hib Brazilian combination vaccine

We evaluated the functional activity of Haemophilus influenzae B (Hib) antibodies elicited in a group of infants immunized with the diphtheria-tetanus-pertussis vaccine combined with an Hib vaccine produced totally in Brazil after technological transfer of Hib vaccine production from Glaxo SmithKline, Belgium. Blood samples from immunized infants (N = 985) were collected for the determination of Hib antibodies. Total Ig and IgM and IgG subclasses of antibodies against polyribosyl ribitol phosphate (PRP) were analyzed by ELISA. Almost all vaccinees (97.56 percent, 961/985) developed a strong anti-PRP IgG antibody response (¡Ý1.0 ¦Ìg/mL), while an anti-PRP IgM response was observed in 64.24 percent (634/985) of them (¡Ý0.15 ¦Ìg/mL). Only 18.88 percent (186/985) of the infants in the group with high PRP antibody IgG concentrations (¡Ý1.0 ¦Ìg/mL) developed a high IgM antibody response. Anti-PRP IgG antibody levels were significantly higher than anti-PRP IgM. These results demonstrate the predominance of IgG antibodies over IgM antibodies in response to PRP, with a ratio of 17:1. IgG antibodies were predominantly of the IgG1 subclass. An increase in IgG avidity was also observed during the course of immunization.

Análise da temperatura axilar e da febre verificadas em um ensaio clínico com vacinas / Analysis of axillary temperature and fever observed in a clinical trial of vaccines

Objetivos: Analisar a temperatura axilar no estudo da vacina contra difteria, tétano, o componente pertussis e hemófilo (DTP/Hib), a frequência de febre e a associação dos eventos adversos. Analisar a metodologia para verificação da temperatura corpórea e febre utilizada em diferentes estudos clínicos com a vacina DTP/Hib. Materiais e métodos: Este trabalho é baseado em dados obtidos do “Estudo de imunogenicidade e reatogenicidade de vacina combinada contra difteria, tétano, pertussis e hemófilo tipo b: validação clínica de produto produzido totalmente no Brasil”, com 1000 lactentes, realizado no município do Rio de Janeiro, no ano de 2006. Foi analisada a temperatura axilar nos tempos 3, 6, 12, 24, 48 e 72 horas após a vacinação. Foram analisadas as associações entre os eventos adversos locais e eventos adversos sistêmicos. Resultados: A freqüência de febre foi de 53,4 % após a primeira dose, 39,9 % após a segunda dose e 31,5 % após a terceira dose nas 24 horas após a vacinação. A freqüência de febre foi diminuindo com a aplicação das doses. Não houve padrão de associação entre os eventos adversos locais e sistêmicos. A mediana da distribuição da temperatura axilar foi maior nos tempos 6 e 12 horas após a vacinação. Conclusões: A definição de febre e as metodologias utilizadas nos estudos clínicos para verificar a temperatura corpórea ainda são heterogêneas, o que dificulta a comparabilidade entre eles.

Objectives: To analyze the axillary temperature in the study of the vaccine DTP/Hib (Martins et al., 2008), the frequency of fever and the association of the adverse events. To analyze themethodology for checking of the corporal temperature and fever used in different clinical trial with the vaccine DTP/Hib. Materials and methods: This work is based on obtained data of the “Study of immunogenicity and reactogenicity of vaccine combined against diphtheria, tetanus, pertussisand haemophylus type b: clinical validation of product produced totally in Brazil ”, with 1000 infants, carried out in the local authority of the Rio of January, in the year of 2006. The axillary temperature was analyzed in the times 3, 6, 12, 24, 48 and 72 hours after the vaccination. The associations were analyzed between the adverse local events and adverse systemic events. Results: The frequency of fever was 53.4 % after the first dose, 39.9 % after the second dose and 31.5 % after the third dose in 24 hours after the vaccination. The frequency of feverwas lessening with the application of the doses. There was no standard of association between the adverse local events and systemic adverse events. The medium one of the distribution ofthe axillary temperature was bigger in the times 6 and 12 hours after the vaccination. Conclusions: The definition of fever and the methodologies used in the clinical studies to check the corporal temperature they are still heterogeneous what makes difficult thecomparability between them.

Immunogenicity, reactogenicity and consistency of production of a Brazilian combined vaccine against diphtheria, tetanus, pertussis and Haemophilus influenzae type b

A randomized, double-blinded study evaluating the immunogenicity, safety and consistency of production of a combined diphtheria-tetanus-pertussis-Haemophilus influenzae type b vaccine entirely produced in Brazil by Bio-Manguinhos and Instituto Butantan (DTP/Hib-BM) was undertaken. The reference vaccine had the same DTP vaccine but the Hib component was produced using purified materials supplied by GlaxoSmithKline (DTP/Hib-GSK), which is registered and has supplied the Brazilian National Immunization Program for over more than five years. One thousand infants were recruited for the study and received vaccinations at two, four and six months of age. With respect to immunogenicity, the vaccination protocol was followed in 95.6 percent and 98.4 percent of infants in the DTP/Hib-BM and DTP/Hib-GSK groups, respectively. For the Hib component of the study, there was 100 percent seroprotection (>0.15 µg/mL) with all three lots of DTP/Hib-BM and DTP/Hib-GSK. The geometric mean titer (GMT) was 9.3 µg/mL, 10.3 µg/mL and 10.3 µg/mL for lots 1, 2 and 3 of DTP/Hib-BM, respectively, and the GMT was 11.3 g/mL for DTP/Hib-GSK. For diphtheria, tetanus and pertussis, seroprotection was 99.7 percent, 100 percent and 99.9 percent, respectively, for DTP/Hib-BM, three lots altogether and 99.2 percent, 100 percent and 100 percent for DTP/Hib-GSK. GMTs were similar across all lots and vaccines. Adverse events rates were comparable among the vaccine groups. The Brazilian DTP/Hib vaccine demonstrated an immunogenicity and reactogenicity profile similar to that of the reference vaccine.

Incidência de episódios hipotônicos-hiporresponsivos associados à vacina combinada DTP/Hib usada no Programa Nacional de Imunizações / Incidence of hypotonic-hyporesponsive episodes associated to the combined DTP/Hib vaccine used in Brazilian National Immunizations Program

OBJETIVO: Avaliar a segurança da vacina combinada de difteria-tétano-coqueluche de células inteiras e Haemophilus influenzae tipo b usada no Programa Nacional de Imunizações, e em especial a incidência de episódios hipotônicos-hiporresponsivos. MÉTODO: Acompanhamento de uma coorte de 21.064 lactentes (20.925 ou 99,7 por cento aderiram ao protocolo de estudo), nas 48 horas após a aplicação da vacina de difteria, tétano, coqueluche de células inteiras e Haemophilus influenzae tipo b em centros de saúde na cidade do Rio de Janeiro, para determinar e investigar eventos adversos graves, espontâneos e solicitados. Cada criança foi monitorada durante somente uma dose. RESULTADOS: A incidência de episódios hipotônicos-hiporresponsivos foi de 1:1.744 doses (casos confirmados) e de 1:1.495 doses (casos confirmados mais casos suspeitos). A taxa de incidência de convulsões foi de 1:5.231 doses. Não foram detectados casos de apnéia. Esses resultados são comparáveis àqueles relatados na literatura para a vacina contra difteria-tétano-coqueluche de células inteiras. CONCLUSÃO: A vacina contra difteria, tétano, coqueluche de células inteiras e Haemophilus influenzae tipo b em estudo pode ser usada com segurança no Programa Nacional de Imunizações, de acordo com as precauções e contra-indicações correntes.

OBJECTIVE:To evaluate the safety of a combined diphtheria-tetanus-whole cell pertussis-Haemophilus influenzae type b vaccine used on the Brazilian National Immunizations Program, chiefly the incidence of hypotonic-hyporesponsive episodes. METHOD: Follow-up of a cohort of 21,064 infants (20,925 or 99.7 percent adhered to the study protocol), within 48 hours of vaccination with diphtheria-tetanus-whole cell pertussis-Haemophilus influenzae type b vaccine in health care units in the City of Rio de Janeiro, to ascertain and investigate spontaneous and solicited severe adverse events. Each child was followed-up for one dose only. RESULTS: The rate of hypotonic-hyporesponsive episodes was 1/1,744 doses (confirmed cases) and 1/1,495 doses (confirmed plus suspect cases). The rate of convulsions was 1/5,231 doses. No cases of apnea were detected. These results are comparable to those found in the literature with diphtheria-tetanus-whole cell pertussis vaccine. CONCLUSION: The diphtheria-tetanus-whole cell pertussis-Haemophilus influenzae type b vaccine under study can be safely used in the National Immunizations Program, according to the current precautions and contraindications.

Incidencia de meningitis y neumonías bacterianas agudas en menores de cinco años: Provincia del Guayas – Ecuador, años 2002 – 2005 / Incidence of meningitis or acute bacterial pneumonias in children less than 5 years old: Province of Guayas – Ecuador, year 2002-2005

Tipo de estudio: prospectivo, descriptivo, longitudinal. Objetivos: determinar la situación epidemiológica de meningitis y neumonías causadas por H. Influenzae tipo b (Hib) y documentar el impacto de la vacuna pentavalente en la incidencia de meningitis y neumonías causadas por Hib. Materiales y métodos: se incluyeron a los niños menores de 5 años que acudieron a la Emergencia del hospital del niño “Dr. Francisco de Ycaza Bustamante” con cuadro clínico sospechoso de meningitis y neumonías bacterianas agudas (MBA y NBA) entre los años 2002 – 2005, a quienes se le realizó punción lumbar con estudio citoquímico y cultivo de LCR; y rx standard de tórax con hemocultivo, respectivamente. Resultados: Se incluyeron 1355 pacientes (206 para meningitis bacteriana aguda y 1119 para neumonía bacteriana aguda) que cumplían con las definiciones de casos sospechosos; al final del período se confirmaron 47 casos de meningitis con aislamiento en laboratorio de haemophilus influenzae; y, de las 487 neumonías bacterianas confirmadas, se aisló en 12 de ellas, el Hib. Así mismo se observó la presencia importante del streptococo pneumoniae como agente causal de 9 casos de meningitis bacteriana y 21 casos de neumonías bacterianas agudas. Conclusiones: el impacto de la vacunación en la reducción de las patologías causadas por el Hib es evidente un año después, a partir del año 2004; así como la tendencia sostenida del streptococo pneumoniae como agente causal de MBA y NBA; la vacuna pentavalente no actúa sobre esta bacteria.

Type of Study: Prospective, descriptive and longitudinal. Objectives: Determine the epidemiology of meningitis and pneumonias caused by H. influenzae type B and Document the impact of immunization in the incindence of meningitis and neumonia caused by Hib. Material and method: Children less than 5 years old who went to the emergency department of “Dr. Francisco de Ycaza Bustamente” Children’s Hospital with a clinical history suspected to be meningitis or acute bacterial pneumonia between the years 2002-2005. This patient underwent lumbar tap for citochemical study and culture of the CSF, a chest x-ray and blood culture. Results: A total of 1355 patients were included in the study in which 206 were diagnosed with acute bacterial meningitis and 1119 with acute bacterial pneumonia. At the end of the study 47 cases of meningitis by H. influnenzae was confirmed and 487 bacterial pneumonias were confirmed only 12 were produced by Hib. Streptococcus pneumoniae was the microorganism for 9 of the cases of bacterial meningitis and for 21 of cases of bacteria pneumonia. Conclusions: The impact of immunization in lowering the incidence of these pathologies caused by HiB is evident a year later during year 2004.

Nasopharyngeal colonization by Haemophilus influenzae in children attending day-care centers, in Ribeirão Preto, State of São Paulo, Brazil

Nasopharyngeal carriage of Haemophilus influenzae (Hi) was studied in 114 healthy children 3 years old, attending day-care centers (DCCs) in Ribeirão Preto, State of São Paulo, Brazil. Biotype, serotype (by specific antisera and PCR) and antibiotic susceptibility to 14 antibiotics of each isolate were determined. Carriage rates of Hi were 72.0%. Isolates belonged to biotype II (36.5%), I (21.5%), V (18.2%) and III (16.1%). The prevalence of encapsulated Hi carriers was 3.2% for type f, 1.0% for type b, 1.0% for type d and 1.0% for type e. Resistances to trimethoprim-sulphamethoxazole and ampicillin were 46.2% and 10.7% respectively. Multidrug resistance was found in 14 (15.0%) of the isolates tested. Among the isolates, 13.9% were beta-lactamase producers; there were no beta-lactamase negative ampicillin resistant isolates. DCCs are niches with a high potential for the spread of microorganisms and should be continuously monitored to detect elimination or replacement of H. influenzae type b colonization.

A colonização da nasofaringe por Haemophilus influenzae (Hi) foi estudada em 114 crianças saudáveis com menos de 3 anos de idade e que freqüentam creches (day-care centers DCC) em Ribeirão Preto, estado de São Paulo, Brasil. Para cada uma das cepas isoladas foram determinados o biótipo, o sorotipo (por antisoro especifico e PCR) e a sensibilidade a 14 antibióticos. A freqüência de colonização por Hi foi de 72,0%. As cepas isoladas foram identificadas como pertencentes aos biótipos II (36,5%), I (21,5%), V (18,2%) e III (16,1%). A freqüência encontrada de cepas encapsuladas foi de 3,2% para o tipo f, 1,0% para o tipo b, 1,0% para o tipo d e 1,0% para o tipo e. A resistência para trimetoprim-sulfametoxazole e ampicilina foi de 46,2% e 10,7% respectivamente. Resistência múltipla foi encontrada em 14 (15,0%) das cepas analisadas. 13,9% das cepas analisadas eram produtoras de beta-lactamase, e não foi recuperada nenhuma cepa beta-lactamase negativa e ampicilina resistente. DCCs são considerados locais de risco, com um alto potencial de disseminação de microrganismos e por isto devem ser continuadamente monitorados com a finalidade de detectar a eliminação da colonização da nasofaringe por cepas H. influenzae tipo b das crianças que freqüentam DCC, ou detectar a sua substituição por outro tipo de cepa.