Vacina TAK-003 tetravalente para a prevenção de infecção pelo vírus da dengue / Quadrivalent TAK-003 vaccine for the prevention of dengue virus infection

INTRODUÇÃO: A dengue é uma arbovirose que cursa com uma doença febril aguda transmitida pelo mosquito Aedes Aegypti. Possui elevada prevalência em regiões tropicais e subtropicais, sendo a mais frequente dentre as arboviroses no contexto mundial. Em 2022, 2.803.096 casos de dengue foram notificados na Região das Américas, com uma taxa de incidência cumulativa de 282 casos por 100.000 habitantes, sendo observado no Brasil o maior número de casos (2.383.001). Classificada como Desastre Natural Biológico, a dengue tem potencial para produzir surtos com grande impacto na rede de atenção de saúde pública. A infecção pelo vírus gera uma doença descrita como dinâmica e sistêmica, que pode ser assintomática, ou se apresentar em sua forma mais benigna com remissão dos sintomas, como também pode raramente agravar-se e levar ao óbito. Medicamentos antivirais não estão disponíveis como forma de tratamento. As medidas de controle dos vetores são efetivas na redução do número de casos. Em 2015 foi autorizada a primeira vacina contra dengue (Dengvaxia®), contudo só deve ser administrada em indivíduos que já foram infectados anteriormente, pois os indivíduos não previamente infectados possuem um risco

Alerta monitoramento do horizonte tecnológico: Vacinas Bivalentes para a prevenção da Covid-19 / Alert monitoring of the technological horizon: Bivalent Vaccines for the prevention of Covid-19

A TECNOLOGIA: Condição clínica: A Covid-19 é uma doença infecciosa causada pelo coronavírus 2 (SARS-CoV2), transmitido principalmente por meio de gotículas e aerossóis respiratórios de pessoa a pessoa. A infecção pode ser disseminada tanto por indivíduos assintomáticos quanto sintomáticos, e os sintomas podem aparecer de dois a 14 dias após a exposição ao vírus. A apresentação clínica da doença Covid-19 é variada. Os sintomas incluem febre, calafrio, tosse, dificuldade respiratória, fadiga, dores musculares, dor de cabeça, perda de paladar e olfato, dor de garganta, congestão nasal e sintomas gastrointestinais. Aproximadamente 5% dos pacientes com Covid-19 e 20% daqueles já hospitalizados apresentam um agravamento da doença, com necessidade de cuidados médicos intensivos. Em 11 de março de 2020, Organização Mundial de Saúde (OMS) declarou status de pandemia da Covid-196. Até o dia 25 de novembro de 2022, foram contabilizados 636.440.663 casos confirmados e 6.606.624 mortes7 pela doença no mundo. No Brasil, foram contabilizados 35.007.209 casos e 688.920 mortes até 19 de novembro de 2022. Após quase três anos de pandemia, o número de mortes devido à doença diminuiu, mesmo com ondas periódicas de aumento de casos que são observadas no mundo. Isso se deve, principalmente, ao avanço da vacinação. Até 23 de novembro de 2022, foram aplicadas, globalmente, um total de 12.959.275.260 de doses de vacina. No entanto, a pandemia de Covid-19 continua sendo um desafio de saúde global contínuo devido ao surgimento de múltiplas variantes do vírus SARS-CoV2. Destaca-se a rápida disseminação global da variante de preocupação ômicron (B.1.1.529, também referida como sublinhagem BA.1) e, mais recentemente, a predominância das sublinhagens ômicron BA.4 e BA.5 (referida como BA.4/BA.5 devido à estrutura similar de suas glicoproteínas spike). Diante da transmissão generalizada em todo o mundo, a OMS criou uma subcategoria de rastreamento, nomeada como sublinhagens de preocupação da variante ômicron. Dados de ensaios clínicos e de estudos de mundo real indicam uma diminuição da proteção após esquema vacinal primário e das doses de reforço ao longo do tempo, além de uma redução da eficácia contra variantes das vacinas originais disponíveis para prevenção da Covid-19. Assim, após o reconhecimento de que a variante ômicron se tornou a cepa circulante globalmente dominante em 2022, os fabricantes rapidamente passaram a desenvolver vacinas de segunda geração, chamadas de bivalentes ou adaptadas. Essas vacinas contêm o código do vírus SARS-CoV-2 original em associação com o código das variantes ômicron, com o objetivo de aumentar a eficácia para a prevenção da Covid-19. DESCRIÇÃO DA TECNOLOGIA: Os laboratórios Pfizer e Moderna desenvolveram e lançaram vacinas bivalentes formuladas com RNA mensageiro (mRNA) que codifica a proteína spike da cepa original do vírus SARS-CoV-2 e o mRNA da variante ômicron (BA.1 ou BA.4/BA.5) do vírus (Quadro 1). O mRNA da cepa original é utilizado para oferecer ampla proteção contra a Covid-19 enquanto o mRNA da ômicron é utilizado para melhorar a proteção contra essa variante. PANORAMA DE DESENVOLVIMENTO: Os ensaios clínicos com o uso das vacinas bivalentes para a profilaxia da Covid-19 foram identificados, inicialmente, na base de pesquisa clínica clinicaltrials.gov. Foram incluídos ensaios clínicos de fases 2, 3 e 4, em andamento ou completos, com o uso das tecnologias para a prevenção da Covid19. Além disso, foram consultadas as bases eletrônicas MEDLINE (via PubMed), EMBASE (via Periódicos Capes) e o Cortellis da Clarivate Analytics para buscar os resultados dos ensaios clínicos. As estratégias de busca foram elaboradas com os termos relacionados à doença e à tecnologia, assim como seus sinônimos e códigos de pesquisa. Todas as buscas foram realizadas em 09 de novembro de 2022. CONSIDERAÇÕES FINAIS: Diante do cenário de disseminação das principais variantes de preocupação estão em desenvolvimento no momento ensaios clínicos com vacinas de diferentes variantes do vírus SARSCoV-2, sozinhas ou associadas à cepa original. As vacinas bivalentes mais adiantadas no seu desenvolvimento são as vacinas dos laboratórios farmacêuticos Pfizer e Moderna, as quais contêm tanto o código da cepa original quanto da variante ômicron BA.1 ou da variante ômicron BA.4/BA.5. Essas vacinas bivalentes já têm aprovação de uso emergencial nas agências sanitárias internacionais e já estão sendo utilizadas como dose de reforço nos respectivos países. No Brasil, ambas as vacinas bivalentes do laboratório Pfizer receberam autorização de uso emergencial pela Anvisa no final do mês de novembro de 2022. Essa aprovação visa ampliar a cobertura vacinal da população como uma ferramenta atualizada de resposta às variantes emergentes, uma vez que dados de mundo real indicam que, na presença da ômicron, a efetividade da dose inicial de reforço com a vacina Comirnaty® monovalente é mais baixa e desaparece mais rapidamente. As evidências indicam que as vacinas bivalentes podem ser utilizadas na população de modo seguro, além de produzir níveis superiores de títulos de anticorpos neutralizantes para as variantes de preocupação mais prevalentes no atual cenário. Os resultados preliminares dos ensaios clínicos mostram que as vacinas bivalentes apresentaram perfis de segurança e reatogenicidade semelhantes àqueles da vacina monovalente, já utilizada em grande escala. As reações adversas comuns foram leves (como dor e inchaço no local de injeção, fadiga, febre e dores de cabeça e nas articulações), sem ocorrência de eventos adversos graves ou miocardite. Quanto à eficácia, os dados de imunogenicidade indicam uma maior neutralização para a variante ômicron BA.1 e BA.4/BA.5. Para dirimir as incertezas existentes e obter dados mais robustos sobre a imunogenicidade e segurança dessas tecnologias, os laboratórios continuarão conduzindo os estudos clínicos com ambas as cepas variantes.

Timeliness of immunisation with the pentavalent vaccine at different levels of the health care system in the Lao People's Democratic Republic: A cross-sectional study.

BACKGROUND: The timely administration of vaccines is considered to be important for both individual and herd immunity. In this study, we investigated the timeliness of the diphtheria-tetanus-whole cell pertussis-hepatitis B-Haemophilus influenzae type b (pentavalent) vaccine, scheduled at 6, 10 and 14 weeks of age in the Lao People's Democratic Republic. We also investigated factors associated with delayed immunization. METHODS: 1162 children aged 8-28 months who had received the full course of the pentavalent vaccine at different levels of the health care system were enrolled. Vaccination dates documented in hospital records and/or immunisation cards were recorded. Age at vaccination and time intervals between doses were calculated. Predictors for timely completion with the pentavalent vaccine at 24 weeks were assessed by bivariate and multivariable analyses. RESULTS: Several discrepancies in dates between vaccination documents were observed. In general, vaccination with the pentavalent vaccine was found to be delayed, especially in health care settings below the provincial hospital level. Compared to the central hospital level, less participants who were vaccinated at the district/health center level received the third dose by 16 (48% at the central hospital level vs. 7.1% at the district and 12.4% at the health center level) and 24 weeks of age (94.4% at the central hospital level vs 64.6% at the district-outreach and 57.4% at the health center level) respectively. In logistic regression analyses, lower education level of the mother as well as vaccination by outreach service, were independently associated with delayed completion of vaccination. CONCLUSION: We observed a general delay of vaccination, especially at lower ranked facilities, which correlated with indicators of poor access to health services. This highlights the need for further improving health equity in rural areas. Age-appropriate vaccination should become a quality indicator for the national immunization programme. In addition, we recommend further training of the health care staff regarding the importance of reliable documentation of dates.

Varicella vaccination in Italy and Germany - different routes to success: a systematic review.

INTRODUCTION: Italy (in pilot regions) and Germany (nationwide) were the first European countries to introduce universal varicella vaccination (UVV) programs. AREAS COVERED: A systematic review was performed to assess varicella epidemiology before UVV programs and the impact of 1-dose and 2-dose UVV programs in Italy and Germany. EXPERT OPINION: Italy implemented 1- or 2-dose UVV programs successively in eight pilot regions between 2003 and 2011 and nationwide in 2017. Germany implemented 1- and 2-dose UVV programs in 2004 and 2009, respectively. While Italy had two nationwide surveillance systems in place for varicella in the pre-vaccination era, in Germany, a mandatory notification system for varicella was only introduced in the New Federal States 2 years before the 1-dose UVV implementation. Substantial reductions in moderate/severe varicella and varicella-related hospitalization incidence occurred during the 1-dose era. Further reductions were reported in Italy and Germany after the recommendation of a second dose in a long or short schedule, respectively. Different benefit-risk evaluations of a tetravalent varicella-containing vaccine (MMRV) used as a first dose led to different recommendations (MMRV versus MMR+V) in these countries. Vaccination strategies in both countries tailored to country-specific needs and goals led to a reduction in varicella-related health care hospitalization costs.

Valuing the cost of improving Chilean primary vaccination: a cost minimization analysis of a hexavalent vaccine.

BACKGROUND: The phased withdrawal of oral polio vaccine (OPV) and the introduction of inactivated poliovirus vaccine (IPV) is central to the polio 'end-game' strategy. METHODS: We analyzed the cost implications in Chile of a switch from the vaccination scheme consisting of a pentavalent vaccine with whole-cell pertussis component (wP) plus IPV/OPV vaccines to a scheme with a hexavalent vaccine with acellular pertussis component (aP) and IPV (Hexaxim®) from a societal perspective. Cost data were collected from a variety of sources including national estimates and previous vaccine studies. All costs were expressed in 2017 prices (US$ 1.00 = $Ch 666.26). RESULTS: The overall costs associated with the vaccination scheme (4 doses of pentavalent vaccine plus 1 dose IPV and 3 doses OPV) from a societal perspective was estimated to be US$ 12.70 million, of which US$ 8.84 million were associated with the management of adverse events related to wP. In comparison, the cost associated with the 4-dose scheme with a hexavalent vaccine (based upon the PAHO reference price) was US$ 19.76 million. The cost of switching to the hexavalent vaccine would be an additional US$ 6.45 million. Overall, depending on the scenario, the costs of switching to the hexavalent scheme would range from an additional US$ 2.62 million to US$ 6.45 million compared with the current vaccination scheme. CONCLUSIONS: The switch to the hexavalent vaccine schedule in Chile would lead to additional acquisition costs, which would be partially offset by improved logistics, and a reduction in adverse events associated with the current vaccines.

Relative Effectiveness of Influenza Vaccines Among the United States Elderly, 2018-2019.

BACKGROUND: Studies among individuals ages ≥65 years have found a moderately higher relative vaccine effectiveness (RVE) for the high-dose (HD) influenza vaccine compared with standard-dose (SD) products for most seasons. Studies during the A(H3N2)-dominated 2017-2018 season showed slightly higher RVE for the cell-cultured vaccine compared with SD egg-based vaccines. We investigated the RVE of influenza vaccines among Medicare beneficiaries ages ≥65 years during the 2018-2019 season. METHODS: This is a retrospective cohort study using inverse probability of treatment weighting and Poisson regression to evaluate RVE in preventing influenza hospital encounters. RESULTS: Among 12 777 214 beneficiaries, the egg-based adjuvanted (RVE, 7.7%; 95% confidence interval [CI], 3.9%-11.4%) and HD (RVE, 4.9%; 95% CI, 1.7%-8.1%) vaccines were marginally more effective than the egg-based quadrivalent vaccines. The cell-cultured quadrivalent vaccine was not significantly more effective than the egg-based quadrivalent vaccine (RVE, 2.5%; 95% CI, -2.4% to 7.3%). CONCLUSIONS: We did not find major effectiveness differences between licensed vaccines used among the elderly during the 2018-2019 season. Consistent with prior research, we found that the egg-based adjuvanted and HD vaccines were slightly more effective than the egg-based quadrivalent vaccines.

Eficacia y seguridad de la vacuna hexavalente que contiene la forma acelular en comparación a la vacuna pentavalente (con componente de células completas) en niños que presentan problemas neurológicos / Efficacy and safety of the hexavalent vaccine containing the acellular form compared to the pentavalent vaccine (with a whole cell component) in children with neurological problems

INTRODUCCIÓN: El presente informe expone la evaluación del uso de la vacuna hexavalente (que contiene la forma acelular de pertusis) en comparación con la vacuna pentavalente utilizada actualmente a nivel nacional (que contiene la forma celular de pertusis), con especial énfasis en los eventos adversos de tipo neurológico en la población de niños con algún problema neurológico de fondo. La pertusis (tos ferina) sigue siendo un importante problema de salud pública en países de medianos y bajos ingresos. Esta enfermedad es causada por la infección de la bacteria Bordetella pertussis. Las manifestaciones más severas incluyen tos prolongada que dura varias semanas, que con frecuencia se presenta en paroxismos que finalizan con un "gallo" inspiratorio. La enfermedad puede ser fatal en niños y lactantes. El esquema nacional de vacunación infantil incluye la vacuna pentavalente, la cual protege contra las infecciones causadas por: Corynebacterium diphtheriae, Clostridium tetani, Bordetella pertussis, Haemophilus influenzae tipo b y el virus de la Hepatitis B (VHB). La combinación de la vacuna contra difteria, tétanos y pertusis se le conoce como DTP. Dependiendo del tipo de componente de la pertusis, se le denomina DTwP o DTaP. Esto debido a que la vacuna puede ser de célula entera, es decir, que incluye al organismo entero de la pertusis (i.e., DTwP o célular), o puede ser acelular, es decir, que la vacuna contiene solo una parte del organismo de la pertusis (i.e., DTaP). Actualmente, dentro del país la vacuna pentavalente utilizada incluye al organismo entero (i.e., DTwP o celular). Así, a la fecha la vacuna pentavalente está disponible dentro del esquema de vacunación nacional; no obstante, existe preocupación, por parte de algunos médicos pediatras de la institución, en que esta vacuna al incluir la versión celular de la pertusis (DTwP) podría aumentar el riesgo de presentar eventos adversos neurológicos en aquellos niños con una condición neurológica de base. Por lo tanto, se ha enviado al IETSI la solicitud de evaluación de la vacuna hexavalente como una alternativa. Esta vacuna aparte de proteger contra la polio, a diferencia de la pentavalente actualmente utilizada, incluye la versión acelular de la pertusis (DTaP). METODOLOGÍA: Se realizó una búsqueda de la literatura con respecto a la eficacia y efectos adversos de tipo neurológico del uso de la vacuna pentavalente (con wP) en niños con problemas neurológicos, respecto al uso de la vacuna hexavalente que contiene la forma aP. Esta búsqueda se realizó utilizando los meta-buscadores: Translating Research into Practice (TRIPDATABASE), National Library of Medicine (PubMed-Medline) y Health Systems Evidence. Adicionalmente, se amplió la búsqueda revisando la evidencia generada por grupos internacionales que realizan revisiones sistemáticas (RS), evaluación de tecnologías sanitarias (ETS) y guías de práctica clínica (GPC), tales como la Cochrane Group, The National Institute for Health and Care Excellence (NICE), the Agency for Health care Research and Quality (AHRQ), The Canadian Agency for Drugs and Technologies in Health (CADTH) y The Scottish Medicines Consortium (SMC). Esta búsqueda se completó ingresando a la página web www.clinicaltrials.gov, para así poder identificar ensayos clínicos en elaboración o que no hayan sido publicados aún y así disminuir el riesgo de sesgo de publicación. RESULTADOS: Se realizó la búsqueda bibliográfica y de evidencia científica para el sustento del uso de la vacuna hexavalente en niños con problemas neurológicos, respecto al uso de la vacuna pentavalente que contiene la forma wP. CONCLUSIONES: Existen disponibles dos tipos de vacunas contra pertusis: la de células enteras (wP) basadas en organismos muertos de B. pertusis y la acelular (aP) basada en uno o más antígenos de pertusis, individuales y altamente purificados. Las vacunas wP se introdujeron ampliamente en los países industrializados en la mitad del siglo XX y se incluyeron en el Programa Ampliado de vacunación (EPI, por sus siglas en inglés) desde 1974.  Las vacunas wP se producen en base al cultivo regular de cepas seleccionadas de Bordetella pertusis que luego son calentadas y tratadas con formalina para inactivarlas y no ser. capaces de replicarse, por lo que son consideradas bacterias muertas., La respuesta inmune a las vacunas wP están dirigidas a una variedad de antígenos de las células de bacterias completas. En este proceso no se pueden eliminar componentes no deseados como la endotoxina, por lo que un nivel aceptable de potencia esta inevitablemente asociado con una mayor incidencia de efectos adversos. Las vacunas de pertusis acelular (aP) se producen mediante la recombinación o aislamiento de antígenos purificados de B. pertusis. Uno o más de estos antígenos extraídos son incluidos en varias combinaciones para producir una vacuna. Los datos de eficacia disponibles favorecen las vacunas aP multi componente ( 3 componentes) sobre las vacunas de uno o dos componentes. La OMS afirma que se puede obtener protección con la inmunización primaria ya sea con la vacuna wP o aP. Aunque las vacunas que contienen wP están más comúnmente asociadas con reactogenicidad local y sistémica, ambas vacunas tienen excelentes registros de seguridad. La OMS recomienda que en caso de que un sistema de salud proponga el reemplazo de la vacuna wP por la aP en el esquema de vacunación primario, este solo debe ser considerado si está asegurado de manera sostenida un booster periódico o la inmunización materna. Esta recomendación procede de los resulados provenientes de los estudios realizados a raíz de un incremento de casos de pertusis en varios países. En una RS Cochrane, la aparición de convulsiones y HHE fueron significativamente menos comunes con las vacunas aP que las vacunas wP para la serie primaria de vacunación, así como para la dosis booster. No se reportaron casos de encefalopatías en los ECA incluidos en esta RS. Según un estudio de vigilancia en Canadá de efectos adversos serios, durante el periodo de 1998-2001 cuando la vacuna wP no estaba disponible, los casos de hospitalizaciones por convulsión y HHE se redujeron comparados con el periodo 1995-1996 en el que la vacuna wP era parte del esquema nacional de vacunación. El informe de la Dirección de Guías de Práctica Clínica, Farmacovigilancia y Tecnovigilancia del IETSI (DGPCFyT), Centro de referencia Institucional de Farmacovigilancia y Tecnovigilancia de EsSalud, concluye que se carece de evidencia suficiente que señale que la vacuna hexavalente (con aP) sea más segura que la pentavalente (con wP) en niños con antecedentes de problemas neurológicos. Existe evidencia de moderada calidad que la vacunación con aP disminuya el riesgo de sufrir de convulsiones o HHE después de recibir la primera vacunación infantil, respecto a la vacuna wP. Esto tiene implicancia clínica importante en niños con condiciones neurológicas de base que podrían tener mayor susceptibilidad o menor umbral para las convulsiones. Considerando que la principal diferencia entre ambas vacunas evaluadas recae en el componente de pertusis, se tomó en consideración otras vacunas distintas a la hexavalente que también incluyen el componente de vacuna acelular (aP). Así, tomando en cuenta solo el costo de la vacuna según la lista de precios del fondo rotatorio de la OPS y asumiendo que se esperaría una eficacia similar entre ambas vacunas aP, se considera que la vacuna pentavalente acelular tendría un mejor perfil de costo-oportunidad que la hexavalente acelular en nuestro sistema de salud. Por lo expuesto, el IETSI, aprueba el uso de la vacuna pentavalente que incluye la pertusis acelular (aP) para niños que presentan problemas neurológicos.

Budget impact analysis of introducing a non-reconstituted, hexavalent vaccine for pediatric immunization in the United Kingdom.

Objectives: Non-reconstituted, hexavalent vaccines (HV-NRs) can facilitate clinical practice by shortening vaccine preparation and administration time and by reducing the risk of vaccination errors compared to combination vaccines requiring reconstitution. The aim of this study was to determine the budget impact of introducing an HV-NR into the United Kingdom's (UK) pediatric immunization program, which currently uses a hexavalent vaccine requiring reconstitution (HV-R). Methods: Abudget impact model covering a 10-year time horizon was developed. The target population constituted closed UK birth cohorts from 2020 to 2029. Total direct costs from the payer's perspective consisted of four main categories: vaccine acquisition and management, healthcare provider's service provision, (non-)contaminated needle-stick and sharps injury (NSI), and non-NSI vaccination error costs. The net budget impact was calculated by comparing the costs in two different market share scenarios. Results: The use of HV-NR instead of HV-R was estimated to save £9,079,927 over a 10-year time horizon (i.e. £907,993 per year). Assuming all other vaccine criteria are equivalent the budget impact was most sensitive to changes in time spent by the healthcare provider and management costs. Conclusion: Results suggest, introducing an HV-NR into the UK's pediatric immunization program is potentially cost saving for the healthcare system.

Vaccinations in prison settings: A systematic review to assess the situation in EU/EEA countries and in other high income countries.

INTRODUCTION: In 2016, more than 600,000 persons were being held in EU/EEA correctional facilities on a given day. People in prison may be at risk of vaccine-preventable diseases. While vaccination recommendations for people in prison exist, little is known on coverage and implementation options. METHODS: We performed a systematic review on existing evidence on vaccination in prison settings in the EU/EEA. We searched peer-reviewed and grey literature following international methodology and reporting standards, to gather records published between 1980 and 2016 in all languages. We analysed quantitative (acceptance, uptake, cost-effectiveness) and qualitative (barriers) outcomes. RESULTS: Out of 7041 identified records, 19 full-text articles were included from peer-reviewed literature and two from grey literature. Of these, 18 reported on hepatitis A and/or B virus (HAV/HBV), two on influenza and one on MMR vaccination. Two studies on HAV vaccine reported varying acceptance (5-91%) and uptake rates (62.9-70.5%). Seven studies reported on HBV vaccination. A comparative study showed a significantly higher uptake of the third HBV vaccine dose with the very rapid (63%) compared to the standard schedule (20%). HBV vaccination was generally well accepted (54-100%), whereas uptake was variable (dose 1:23-100%, dose 2:48-92%, dose 3:19-80%). One study on the combined HAV/HBV vaccine reported an acceptance rate of 34%, and declining uptake following dose 1. One study on influenza vaccine showed an uptake of 42-46%, while another reported a MMR vaccine acceptance of 80% and an uptake of 74%. Overall, main reasons for non-vaccination included release from/or transfer between prisons, and refusal. CONCLUSIONS: This systematic review highlighted important knowledge gaps and operational challenges for vaccination in prison settings. Vaccination is an effective measure that warrants comprehensive and tailored implementation to reduce the preventable disease burden, avoid risks of large outbreaks of vaccine-preventable diseases, and contribute to health equity for people in prison.

Lessons learnt from implementing community engagement interventions in mobile hard-to-reach (HTR) projects in Nigeria, 2014-2015.

BACKGROUND: The year 2014 was a turning point for polio eradication in Nigeria. Confronted with the challenges of increased numbers of polio cases detected in rural, hard-to-reach (HTR), and security-compromised areas of northern Nigeria, the Nigeria polio program introduced the HTR project in four northern states to provide immunization and maternal and child health services in these communities. The project was set up to improve population immunity, increase oral polio vaccine (OPV) and other immunization uptake, and to support Nigeria's efforts to interrupt polio transmission by 2015. Furthermore, the project also aimed to create demand for these services which were often unavailable in the HTR areas. To this end, the program developed a community engagement (CE) strategy to create awareness about the services being provided by the project. The term HTR is operationally defined as geographically difficult terrain, with any of the following criteria: having inter-ward/inter-Local Government Area/interstate borders, scattered households, nomadic population, or waterlogged/riverine area, with no easy to access to healthcare facilities and insecurity. METHODS: We evaluated the outcome of CE activities in Kano, Bauchi, Borno, and Yobe states to examine the methods and processes that helped to increase OPV and third pentavalent (penta3) immunization coverage in areas of implementation. We also assessed the number of community engagers who mobilized caregivers to vaccination posts and the service satisfaction for the performance of the community engagers. RESULTS: Penta3 coverage was at 22% in the first quarter of project implementation and increased to 62% by the fourth quarter of project implementation. OPV coverage also increased from 54% in the first quarter to 76% in the last quarter of the 1-year project implementation. CONCLUSIONS: The systematic implementation of a CE strategy that focused on planning and working with community structures and community engagers in immunization activities assisted in increasing OPV and penta3 immunization coverage.

Hexavalent vaccines: increasing options for policy-makers and providers. A review of the data supporting interchangeability (substitution with vaccines containing fewer antigens) and mixed schedules from the same manufacturer.

INTRODUCTION: Combination vaccines improve vaccine uptake and open the infant immunization space for additional vaccines. Hexavalent vaccines have been marketed since 2000. Infanrix hexa (combined diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliovirus-Haemophilus influenzae type b conjugate vaccine, DTPa-HBV-IPV/Hib, GSK) is longest on the market, providing 16 years post-marketing experience. Each DTPa-HBV-IPV/Hib vaccine component is licensed alone and/or in smaller combination vaccines. Programmatic considerations sometimes require an interchange between vaccines due to unavailability, program change or mixed schedules (when the number of required antigens differs across scheduled primary vaccination visits). AREAS COVERED: Immunogenicity and safety data from 11 GSK-sponsored clinical trials support the interchangeability of DTPa-HBV-IPV/Hib within the same vaccines family, and use of DTPa-HBV-IPV/Hib in mixed primary vaccination schedules. EXPERT COMMENTARY: Data show acceptability of interchange of DTPa-HBV-IPV/Hib with other products within the same vaccines family and its use in mixed immunization schedules. This aligns with WHO recommendations that vaccines of the same family from the same manufacturer be used to complete the infant vaccination schedule. Interchangeability and suitability for use in mixed schedules is of interest for policy-makers/providers in the framework of vaccination recommendations as it provides flexibility. Given the complexity of larger combination vaccines, interchangeability or sequential use needs careful assessment.

A decision analytic model for prevention of hepatitis B virus infection in Sub-Saharan Africa using birth-dose vaccination.

OBJECTIVE: To compare prenatal maternal hepatitis B virus (HBV) screening and infant vaccination strategies to inform policy on HBV prevention in Sub-Saharan Africa. METHODS: A decision analytic model was created using previously published data to assess the ability of three intervention strategies to prevent HBV infection by age 10 years. Strategy 1 comprised of universal vaccination with a pentavalent vaccine (HBV, diphtheria, tetanus, pertussis, and Haemophilus influenzae) at age 6 weeks. Strategy 2 comprised of universal HBV vaccine at birth plus pentavalent vaccine. Strategy 3 comprised of maternal prenatal HBV screening and targeted HBV vaccine at birth for all exposed infants plus pentavalent vaccine. The reference strategy provided neither maternal screening nor infant vaccination. Rates of HBV infection and costs were compared. RESULTS: The reference strategy had an HBV infection rate of 2360 per 10 000 children. The HBV infection rate for strategy 1 was 813 per 10 000 children vaccinated (1547 cases prevented). Strategies 2 and 3 prevented an additional 384 cases and 362 cases, respectively. Inclusion of HBV vaccination at birth was the preferred approach at a willingness-to-pay threshold of US$150. CONCLUSION: Including a birth-dose HBV vaccine in the standard schedule was both cost-effective and prevented additional infections.

Vaccine adverse events in a safety net healthcare system and a managed care organization.

BACKGROUND: The Institute of Medicine, in a 2013 report, recommended that the Vaccine Safety Datalink (VSD) expand collaborations to include more diversity in the study population. Kaiser Permanente Colorado (KPCO), an established VSD site, partnered with Denver Health (DH), an integrated safety net healthcare system, to demonstrate the feasibility of integrating DH data within the VSD. Prior to incorporating the data, we examined the identification of specific vaccine associated adverse events (VAEs) in these two distinct healthcare systems. METHODS: We conducted retrospective cohort analyses within KPCO and DH to compare select VAEs between the two populations. We examined the following associations between January 1, 2004 and December 31, 2013: Measles, Mumps, and Rubella (MMR) vaccine and febrile seizures in children 2years and younger, intussusception after rotavirus vaccine in infants 4-34weeks, syncope after adolescent vaccines (Tetanus, Diphtheria, acellular Pertussis; Meningococcal and Human Papillomavirus) in adolescents 13-17years and medically attended local reactions after pneumococcal polysaccharide (PPSV23) vaccine in adults 65years and older. Both sites used similar data procurement methods and chart review processes. RESULTS: For seizures after MMR vaccine (KPCO - 3.15vs. DH - 2.97/10,000 doses) and syncope after all adolescent vaccines (KPCO - 3.0vs. DH - 2.37/10,000 doses), the chart confirmed rates were comparable at the two sites. However, for medically attended local reactions after PPSV23, there were differences in chart confirmed rates between the sites (KPCO - 31.65vs. DH - 14.90/10,000 doses). For intussusception after rotavirus vaccine, the number of cases was too low to make a valid comparison (KPCO - 0vs. DH - 0.13/10,000 doses). CONCLUSION: We demonstrated that data on important targeted VAEs can be captured at DH and rates appear similar to those at KPCO. Work is ongoing on the optimal approach to assimilate DH data as a potential safety net healthcare system in the VSD.

Statistical and Ontological Analysis of Adverse Events Associated with Monovalent and Combination Vaccines against Hepatitis A and B Diseases.

Vaccinations often induce various adverse events (AEs), and sometimes serious AEs (SAEs). While many vaccines are used in combination, the effects of vaccine-vaccine interactions (VVIs) on vaccine AEs are rarely studied. In this study, AE profiles induced by hepatitis A vaccine (Havrix), hepatitis B vaccine (Engerix-B), and hepatitis A and B combination vaccine (Twinrix) were studied using the VAERS data. From May 2001 to January 2015, VAERS recorded 941, 3,885, and 1,624 AE case reports where patients aged at least 18 years old were vaccinated with only Havrix, Engerix-B, and Twinrix, respectively. Using these data, our statistical analysis identified 46, 69, and 82 AEs significantly associated with Havrix, Engerix-B, and Twinrix, respectively. Based on the Ontology of Adverse Events (OAE) hierarchical classification, these AEs were enriched in the AEs related to behavioral and neurological conditions, immune system, and investigation results. Twenty-nine AEs were classified as SAEs and mainly related to immune conditions. Using a logistic regression model accompanied with MCMC sampling, 13 AEs (e.g., hepatosplenomegaly) were identified to result from VVI synergistic effects. Classifications of these 13 AEs using OAE and MedDRA hierarchies confirmed the advantages of the OAE-based method over MedDRA in AE term hierarchical analysis.

[Economic evaluation on different two-dose-vaccination-strategies related to Measles, Mumps and Rubella Combined Attenuated Live Vaccine].

OBJECTIVE: To evaluate the economic effect of Measles, Mumps and Rubella Combined Attenuated Live Vaccine (MMR) under different two-dose vaccination programs. METHODS: A hypothetical birth cohort of 750 000 infants over their lifetime, was followed up from birth through death in Zhejiang province. The current MMR vaccination strategie would include three different ones: 1) Childlern were vaccinated with Measles-Rubella Combined Attenuated Live Vaccine and MMR, respectively at the age of 8 months and 18 months. 2) Children receive MMR at 8 months and 18 months, 3) Strategy 1 plus an additional vaccination of MMR at 4 years of age. Incremental cost-effectiveness ratio (ICER), incremental cost-benefit ratio (ICBR) and incremental net benefit (INB) were applied to calculate the health economic difference for Strategy 2 and Strategy 3 as compared to Strategy 1. Univariate sensitivity analysis was used to assess the robustness of results with main parameters, including the rate of immunization coverage, effectiveness of the vaccines, incidence and burdens of the related diseases, cost of vaccines and the vaccination program itself. RESULTS: ICER, ICBR and INB for Strategy 2 and Strategy 3 appeared as 2 012.51∶1 RMB Yuan per case and 4 238.72∶1 RMB Yuan per case, 1∶3.14 and 1∶1.58, 21 277 800 RMB Yuan and 9 276 500 RMB Yuan, respectively. Only slight changes (<20%) were found under the univariate sensitivity analysis, with varied values on main parameters. CONCLUSION: Based on the current national immunization program, infants vaccinated with MMR at 8 months of age, generated more health economic effects than the Strategy 3.

How a New Health Intervention Affects the Health Systems? Learnings from Pentavalent Vaccine Introduction in India.

OBJECTIVES: To summarize the findings from a Post Introduction Evaluation (PIE) of pentavalent vaccine in Tamil Nadu and Kerala state of India and to understand how the health systems could be prepared for (prior to) introducing a new intervention and how such introduction could affect the health systems (afterwards). METHODS: A post introduction evaluation (PIE) of Haemophilus influenzae type b (Hib) as pentavalent (DPT + HepB + Hib) vaccine was conducted in Tamil Nadu and Kerala states of India in July-Aug 2012. The PIE was conducted as per World Health Organization PIE methods and tools specifically adapted for India. This PIE adopted a 'mixed method approach' with qualitative data focus. RESULTS: The planning for the introduction of pentavalent vaccine provided opportunities to strengthen various functions of the health system i.e., piloting of Open Vial Policy, strengthening surveillance system, improving Adverse Events Following Immunization (AEFI) reporting system and formation of the technical expert groups. It provided opportunity for bringing attention on the immunization programme in general as well. After the vaccine introduction, the beneficial effects were noted on stewardship (increased oversight by top level policy makers and programme managers), creating resources (investment and trainings of staff in immunization), service delivery (increased coverage with the vaccines and improved quality of services) and financing (increased financial allocation and reduced out of pocket expenditures as more people started attending public health facilities). The vaccine introduction was found to be associated with improvement in the health equity, efficiency and service utilization (effective coverage). CONCLUSIONS: New vaccine introduction provides opportunities (both before and after) for strengthening the health systems in setting such as India. Preparing the health system for new challenges has potential to strengthen the health systems, if done in well-coordinated and planned manner. Considering that essential steps are largely similar, these lessons could be applicable for the introduction of other new health interventions in the similar settings.

Assessment of preparation time with fully-liquid versus non-fully liquid paediatric hexavalent vaccines. A time and motion study.

BACKGROUND AND AIMS: Simplified vaccine preparation steps would save time and reduce potential immunisation errors. The aim of the study was to assess vaccine preparation time with fully-liquid hexavalent vaccine (DTaP-IPV-HB-PRP-T, Sanofi Pasteur MSD) versus non-fully liquid hexavalent vaccine that needs reconstitution (DTPa-HBV-IPV/Hib, GlaxoSmithKline Biologicals). METHODS: Ninety-six Health Care Professionals (HCPs) participated in a randomised, cross-over, open-label, time and motion study in Belgium (2014). HCPs prepared each vaccine in a cross-over manner with a wash-out period of 3-5min. An independent nurse assessed preparation time and immunisation errors by systematic review of the videos. HCPs satisfaction and preference were evaluated by a self-administered questionnaire. RESULTS: Average preparation time was 36s for the fully-liquid vaccine and 70.5s for the non-fully liquid vaccine. The time saved using the fully-liquid vaccine was 34.5s (p≤0.001). On 192 preparations, 57 immunisation errors occurred: 47 in the non-fully liquid vaccine group (including one missing reconstitution of Hib component), 10 in the fully-liquid vaccine group. 71.9% of HCPs were very or somewhat satisfied with the ease of handling of both vaccines; 66.7% and 67.7% were very or somewhat satisfied with speed of preparation in the fully-liquid vaccine and the non-fully liquid vaccine groups, respectively. Almost all HCPs (97.6%) stated they would prefer the use of the fully-liquid vaccine in their daily practice. CONCLUSIONS: Preparation of a fully-liquid hexavalent vaccine can be completed in half the time necessary to prepare a non-fully liquid vaccine. The simplicity of the fully-liquid hexavalent vaccine preparation helps optimise reduction of immunisation errors.

Cost-effectiveness of routine varicella vaccination using the measles, mumps, rubella and varicella vaccine in France: an economic analysis based on a dynamic transmission model for varicella and herpes zoster.

PURPOSE: Each year in France, varicella and zoster affect large numbers of children and adults, resulting in medical visits, hospitalizations for varicella- and zoster-related complications, and societal costs. Disease prevention by varicella vaccination is feasible, wherein a plausible option involves replacing the combined measles, mumps, and rubella (MMR) vaccine with the combined MMR and varicella (MMRV) vaccine. This study aimed to: (1) assess the cost-effectiveness of adding routine varicella vaccination through MMRV, using different vaccination strategies in France; and (2) address key uncertainties, such as the economic consequences of breakthrough varicella cases, the waning of vaccine-conferred protection, vaccination coverage, and indirect costs. METHODS: Based on the outputs of a dynamic transmission model that used data on epidemiology and costs from France, a cost-effectiveness model was built. A conservative approach was taken regarding the impact of varicella vaccination on zoster incidence by assuming the validity of the hypothesis of an age-specific boosting of immunity against varicella. FINDINGS: The model determined that routine MMRV vaccination is expected to be a cost-effective option, considering a cost-effectiveness threshold of €20,000 per quality-adjusted life-year saved; routine vaccination was cost-saving from the societal perspective. Results were driven by a large decrease in varicella incidence despite a temporary initial increase in the number of zoster cases due to the assumption of exogenous boosting. In the scenario analyses, despite moderate changes in assumptions about incidence and costs, varicella vaccination remained a cost-effective option for France. IMPLICATIONS: Routine vaccination with MMRV was associated with high gains in quality-adjusted life-years, substantial reduction in the occurrences of varicella- and zoster-related complications, and few deaths due to varicella. Routine MMRV vaccination is also expected to provide reductions in costs related to hospitalizations, medication use, and general-practitioner visits, as well as indirect costs, and it is expected to be a cost-effective intervention in France (GSK study identifier: HO-12-6924).

Hidden efficiencies: making completion of the pediatric vaccine schedule more efficient for physicians.

The objective of this work is to demonstrate the potential time and labor savings that may result from increased use of combination vaccinations. The study (GSK study identifier: HO-12-4735) was a model developed to evaluate the efficiency of the pediatric vaccine schedule, using time and motion studies. The model considered vaccination time and the associated labor costs, but vaccination acquisition costs were not considered. We also did not consider any efficacy or safety differences between formulations. The model inputs were supported by a targeted literature review. The reference year for the model was 2012. The most efficient vaccination program using currently available vaccines was predicted to reduce costs through a combination of fewer injections (62%) and less time per vaccination (38%). The most versus the least efficient vaccine program was predicted to result in a 47% reduction in vaccination time and a 42% reduction in labor and supply costs. The estimated administration cost saving with the most versus the least efficient program was estimated to be nearly US $45 million. If hypothetical 6- or 7-valent vaccines are developed using the already most efficient schedule by adding additional antigens (pneumococcal conjugate vaccine and Haemophilus influenzae type b) to the most efficient 5-valent vaccine, the savings are predicted to be even greater. Combination vaccinations reduce the time burden of the childhood immunization schedule and could create the potential to improve vaccination uptake and compliance as a result of fewer required injections.

Combination vaccines in the South African setting.

The number of vaccines available and included as part of the national immunization schedules, has increased significantly over the past few decades. This impacts on patient/parent compliance and creates a challenge for health care providers for implementation of schedules necessitating training and infrastructure improvements. Use of combination rather than component vaccines offers advantages for compliance by single dose administration of various antigens, reducing stock costing as well as reducing cost of additional health care visits. Combination vaccines are often significantly more expensive than individual constituent vaccines. Concerns regarding an increased incidence of adverse events with use of combination vaccines have not been confirmed and rates may seem high as the adverse events seem to mimic the sum total of adverse event rates for each individual antigen used but may in fact be lower. Manufacturers typically advise against interchanging use of vaccine products. Despite this, health authorities advocate use of an alternative vaccine where the original vaccine in not available, to ensure continuity of vaccination. A notable exception is the acellular pertussis vaccine. Partly, because no serological correlates of immunity exist, but also a general lack of convincing follow up studies has prompted the recommendation for manufacturer fidelity for at least the first 3 vaccine doses. According to the South African Medicines Formulary, a variety of vaccines are available in South Africa. Although a large number are available in the private sector, the only true combination vaccine included in the current state EPI, modified in 2009, is the DTaP-IPV/Hib vaccine (Diphtheria, Tetanus, acellular Pertussis, inactivated Poliomyelitis virus and Haemophilus influenzae type b). There are many reasons justifying the use of combination vaccines rather that the individual constituent formulations. Implementation of use in the South African setting at this point is still limited, but may offer an exciting avenue of expanding the antigen repertoire without impacting on side-effects, efficacy or complexity of scheduling.