Study on the failure time of the vaccine vial monitor used for oral poliovirus vaccine at 25 ℃ and 37 ℃ / 中华预防医学杂志

Objective@#To evaluate the failure time of vaccine vial monitor (VVM) used for oral poliovirus vaccine (OPV) at 25 ℃ and 37 ℃.@*Methods@#160 copies of VVM were produced by a company, the model was QM5D37A, samples were taken from different batches by using the method of random number table . 100 bottles of vaccine were produced by a domestic company, and samples were taken from different batches by using the method of random number table. 160 copies of labels were placed in the incubator at 25 ℃ and 37 ℃, which were used to measure the mutative color of the active region. When the values of color were equal to 40, the color of active region was the same with the reference color, and the VVM was failed. 100 bottles of vaccine were placed in the incubator at 25 ℃ and 37 ℃, which were used to measure the vaccine titer. When total vaccine titer was less than 6.12 CCID50 or vaccine titer of typeⅠ was less than 6.0 CCID50 or vaccine titer of type Ⅲ was less than 5.5 CCID50, the vaccine was failed. We drew the graph of mutative color to calculate the failure time range of VVM According to the graph , we can determine that whether the failure time of VVM was later than the time of vaccines by the data of OPV .@*Results@#The earliest failure time of OPV was 21 days at 25 ℃, and the number of samples was one; The earliest Failure time of VVM was 12.5 days at 25 ℃, and it was less than the earliest failure time of OPV. The earliest failure time of OPV was 4.0 days at 37 ℃, and the number of samples was one; The earliest Failure time of VVM was 3.1 days at 37 ℃, and it was equal to the earliest failure time of OPV.@*Conclusion@#We could know that the failure time of VVM was always earlier than the failure time of vaccines at the same temperatures . The latest failure time of VVM was equal to the earliest failure time of vaccines at 37 ℃. All of the failure times of samples were earlier than that of vaccines at 25 ℃.

Polio inactivated vaccine costs into routine childhood immunization in Brazil / Custos da vacina inativada de pólio na imunização infantil de rotina no Brasil

OBJECTIVE To analyze the costs of vaccination regimens for introducing inactivated polio vaccine in routine immunization in Brazil. METHODS A cost analysis was conducted for vaccines in five vaccination regimens, including inactivated polio vaccine, compared with the oral polio vaccine-only regimen. The costs of the vaccines were estimated for routine use and for the “National Immunization Days”, during when the oral polio vaccine is administered to children aged less than five years, independent of their vaccine status, and the strategic stock of inactivated polio vaccine. The presented estimated costs are of 2011. RESULTS The annual costs of the oral vaccine-only program (routine and two National Immunization Days) were estimated at US$19,873,170. The incremental costs of inclusion of the inactivated vaccine depended on the number of vaccine doses, presentation of the vaccine (bottles with single dose or ten doses), and number of “National Immunization Days” carried out. The cost of the regimen adopted with two doses of inactivated vaccine followed by three doses of oral vaccine and one “National Immunization Day” was estimated at US$29,653,539. The concomitant replacement of the DTPw/Hib and HepB vaccines with the pentavalent vaccine enabled the introduction of the inactivated polio without increasing the number of injections or number of visits needed to complete the vaccination. CONCLUSIONS The introduction of the inactivated vaccine increased the annual costs of the polio vaccines by 49.2% compared with the oral vaccine-only regimen. This increase represented 1.13% of the expenditure of the National Immunization Program on the purchase of vaccines in 2011. .

OBJETIVO Analisar os custos de esquemas de vacinação para a introdução da vacina inativada de pólio na imunização de rotina no Brasil. MÉTODOS Foi realizada análise de custos das vacinas de cinco esquemas de vacinação, incluindo vacina pólio inativada, comparados ao esquema apenas-vacina oral de pólio. Foram estimados custos das vacinas para rotina, para os “Dias Nacionais de Imunização”, quando a vacina de pólio oral é administrada para menores de cinco anos, independentemente da situação vacinal, e do estoque estratégico de vacina pólio inativada. Os custos estimados foram os de 2011. RESULTADOS Os custos anuais do programa apenas-vacina de pólio oral (de rotina e de dois Dias Nacionais de Imunização) foram estimados em US$19.873.170. Os custos incrementais da inclusão da vacina pólio inativada dependeram: do número de doses da vacina, da apresentação da vacina (frascos com dose única ou dez doses) e do número de “Dias Nacionais de Imunização” realizados. O esquema adotado, com duas doses de VIP seguidas de três doses de VOP e um “Dia Nacional de Imunização”, foi estimado em US$29.653.539. A concomitante substituição das vacinas DTPw/Hib e HepB pela vacina pentavalente permitiu a introdução da vacina pólio inativada sem aumento do número de injeções ou visitas necessárias para completar a vacinação. CONCLUSÕES A introdução da vacina pólio inativada aumentou os custos anuais das vacinas de pólio em 49,2%, comparado ao esquema apenas-vacina de pólio oral. Esse aumento representou 1,13% dos gastos do Programa Nacional de Imunização com a compra de vacinas em 2011. .

Ausencia de circulación de poliovirus en departamentos colombianos con coberturas vacunales inferiores a 80% / Absence of poliovirus circulation in Colombian departaments with vaccination coverage below 80%

El presente estudio se propuso explorar la posible circulación silente de poliovirus salvajes y derivados de la vacuna (VDPV, por sus siglas en inglés), en departamentos de Colombia con cobertura de vacunación para polio (OPV, por sus siglas en inglés) menor de 80%. Se colectaron 52 muestras de aguas residuales que se concentraron mediante precipitación con polietilenglicol y cloruro de sodio. La detección viral se realizó mediante aislamiento y la identificación por neutralización del efecto citopático, así como mediante reacción en cadena de la polimerasa convencional y en tiempo real, posterior a la transcripción reversa (TR-RCP y rTR-RCP). Los poliovirus aislados se caracterizaron por secuenciación del gen VP1. En dos de las 52 muestras hubo presencia de poliovirus Sabin 2 con más de 99% de similitud de secuencia con la cepa OPV Sabin 2. Se detectó circulación de enterovirus no polio en 17,3% de las muestras. Los serotipos identificados correspondieron a coxsackievirus B1, echovirus 30 y echovirus 11. No se detectaron evidencias de circulación de VDPV ni poliovirus salvaje en los departamentos de Colombia con coberturas de OPV inferiores a 80%.

This study aims to explore a possible silent circulation of wild and vaccine-derived polioviruses in departments of Colombia with polio vaccination coverage of below 80%. The study collected 52 samples of wastewater concentrated as a result of precipitation with polyethylene glycol and sodium chloride. The viral detection was carried out through isolation and the identification through neutralization of the cytopathic effect, as well as through a conventional polymerase chain reaction following reverse transcription. The isolated polioviruses were characterized by the VP1 gene sequence. In two of the 52 samples, there was a presence of the Sabin type 2 poliovirus with more than 99% sequence similarity with the Sabin type 2 strain polio. Circulation of the nonpolio enterovirus was detected in 17.3% of the samples. The serotypes identified corresponded to coxsackievirus B1, echovirus 30, and echovirus 11. No evidence of the spread of either vaccine-derived poliovirus or wild poliovirus was detected in the departments of Colombia with polio coverage lower than 80%

Vacina contra poliomielite: um novo paradigma: [revisão] / Polio vaccines: a new paradigma: [review]

OBJETIVO: Analisar as estratégias propostas pela Organização Mundial da Saúde (OMS) para controle da poliomielite. FONTES DE DADOS: Levantamento das publicações sobre poliomielite indexadas no Medline, Lilacs e sites da OMS e Ministério da Saúde de janeiro de 2000 a dezembro de 2006. SÍNTESEDOS DADOS: O reconhecimento da paralisia associada aos vírus vacinais e por vírus circulantes derivados da vacina oral não deixa dúvidas de que, em breve, será necessário interromper o uso da vacina oral para poliomielite. Após os vírus selvagens serem erradicados, a vacina oral para poliomielite deverá ser interrompida, de preferência de forma sincronizada em todos os países. Após a interrupção da vacinação, as populações voltarão a ser suscetíveis à poliomielite, podendo ocorrer surtos da doença por vírus selvagens (escape dos laboratórios de forma acidental ou por bioterrorismo). Nos países que já utilizam a vacina para poliomielite com vírus inativado é pouco provável que haja interrupção da vacinação. Países que atualmente utilizam exclusivamente a vacina oral ficarão na dependência da vigilância epidemiológica e dos estoques de vacina oral para controlar eventuais surtos de pólio. Se a vacina oral para poliomielite for reintroduzida nessas populações, haverá novamente o risco de paralisia associada aos vírus vacinais e por vírus circulantes derivados da vacina oral, que podem se disseminar rapidamente para outras regiões e países vizinhos. CONCLUSÕES: É necessário planejar a introdução da vacina para poliomielite com vírus inativado no calendário de rotina brasileiro, assim como adquirir tecnologia para sua produção, que atualmente é insuficiente para as necessidades globais.

OBJECTIVE: Review the World Health Organization (WHO) strategies for poliomyelitis control. DATA SOURCES: Retrieval of publications on poliomyelitis indexed in Medline, Lilacs and in the WHO and Health Ministry sites, from January 2000 to December 2006. DATA SYNTHESIS: Acknowledgement of vaccine-associated paralysis and oral vaccine-derived circulating viruses' paralysis shall certainly require discontinuation of oral vaccination for poliomyelitis use in a short time. After eradication of the wild viruses, oral vaccination for poliomyelitis should be discontinued, preferably in a synchronized manner in all the countries. After termination of vaccination programs, people will become susceptible again to poliomyelitis virus and disease outbreaks caused by wild viruses may occur (accidental escape from laboratories or bioterrorism). In countries already using inactivated poliovirus vaccine, it is unlikely that vaccination will be interrupted. Countries that currently use exclusively oral poliovirus vaccine will have to rely on epidemiological surveillance and on oral vaccine inventories to control potential polio outbreaks. If the oral poliovirus vaccine is reintroduced in those populations, there will be again a risk for vaccine-associated paralysis and oral vaccine-derived circulating viruses' that may spread rapidly to other regions and to nearby countries. CONCLUSIONS: Inactivated poliovirus vaccine introduction in the routine Brazilian vaccination calendar should be programmed as well as acquisition of technology for inactivated poliovirus vaccine production since the latter is currently insufficient to cover global demand.