Padronização de teste para quantificar anticorpos anti-poliovírus utilizando vírus vacinal / Standardization of a test for quantifying the antibodies against poliovirus using the vaccine virus

A poliomielite é uma doença endêmica no Afeganistão e no Paquistão, apesar dos esforços para ser erradicada, representando uma ameaça para outros países principalmente devido às viagens internacionais. A Organização Mundial da Saúde (OMS) tem como objetivo erradicar a poliomielite causada pelo poliovírus selvagem no mundo. O requisito essencial para a erradicação da poliomielite é a eliminação da cepa do poliovírus selvagem, que é empregada no teste padrão-ouro. Com o intuito de auxiliar na erradicação do poliovírus selvagem, o objetivo deste estudo foi modificar o teste padrão-ouro usando o poliovírus derivado da vacina oral atenuada. Foram testados 63 soros pelo ensaio de neutralização utilizando-se antígenos vacinais. A concordância do sorotipo 1 (k=0,74) foi considerada substancial, enquanto o sorotipo 2 (k=1,00) e sorotipo 3 (k= 0,95) foram consideradas quase perfeitas. A sensibilidade dos testes de soroneutralização utilizando os sorotipos 1, 2 e 3 foi de 94,83%, 100,00% e 100,00%, respectivamente. Em conclusão, o ensaio com antígenos vacinais pode ser usado como procedimento laboratorial seguro, especialmente em estudos de vigilância em larga escala.

Poliomyelitis is an endemic disease in Afghanistan and Pakistan in despite of the efforts to eradicate it, and it represents a threat to other countries mainly due to the international trips. The World Health Organization (WHO) aims at eradicating the polio disease worldwide. An essential requirement for eradicating the poliomyelitis is the elimination of the wild poliovirus strain, which is employed in the gold standard test. As a support for the eradication of wild poliovirus, the present study aimed at modifying the gold standard test by using poliovirus derived from the oral attenuated vaccine. Sixty-three sera samples were tested by neutralization assay using vaccine antigens. The degree of agreement of the serotype 1 (k=0.74) was considered substantial, while the serotype 2 (k=1.00) and 3 (k= 0.95) showed almost perfect agreement. The sensitivity of serotypes 1, 2 and 3 was 94.83%, 100.00% and 100.00%, respectively. In conclusion, the assay with the vaccine antigens can be used as a safe application, especially for large-scale surveillance studies.

Poliomielite no Brasil: do reconhecimento da doença ao fim da transmissão / Polio in Brazil: from recognition of the disease to the end of transmission

Neste livro se relata de forma clara, precisa e detalhada a evolução dos fatos e as circunstâncias em que eles se desenvolveram no Brasil, propiciando ao leitor uma visão ampla e integrada dessa aventura fascinante. Os aspectos técnicos e organizacionais das fases evolutivas dessa longa jornada na persecução sucessiva de objetivos de controle, eliminação e erradicação da doença revelam um processo de contínua aprendizagem nos campo político-institucional, tecnocientífico e social, que teve aplicação em outras áreas de atuação do setor Saúde

Nota Histórica / Historical Note

Resumen Una de las grandiosas experiencias a nivel mundial ha sido la vacunación contra la poliomielitis así como también lo fue en su momento la vacunación contra la viruela. Posiblemente con la ayuda de mejores condiciones sanitarias de las poblaciones (al ser una enfermedad de transmisión oral-fecal) estamos en las puertas de la erradicación, pero sobre todo gracias a la intervención con las vacunas contra la polio, tanto la inactivada como la oral. No serán tratados los temas técnicos de las vacunas utilizadas, ambas han sido extraordinarias herramientas para llegar a este momento. No puede ser más oportuna la cita de William Shakespeare: "el pasado es el prólogo", colocada en un mármol a la entrada de un edificio público en Washington DC.

Seronegativity to polio viruses among previously immunized adult candidates to solid organ transplantation

ABSTRACT In the current effort to eliminate polio from the world, it is important to recognize and vaccinate susceptible groups, especially immunocompromised patients living in countries where attenuated polio vaccine is still used. In this report, we describe the frequency of protective antibodies in a small sample of adult SOT candidates in whom previous vaccination could be ascertained. Patients included in this report were selected among the participants of an ongoing prospective study carried out at the Reference Center for Special Immunobiologicals of the Evandro Chagas National Institute of Infectious Diseases in Rio de Janeiro, Brazil. Among the first 100 patients enrolled in this study, only seven adult SOT candidates had proven polio vaccination at childhood. Three of these seven patients (43%) had no protective antibody titers to one or more poliovirus subtype before solid organ transplant. Proven childhood vaccination against polio does not reliably provide lifelong protective antibody titers for adult SOT candidates and should not be used as a criterion to analyze the need for vaccination in this population.

What is the importance of vaccine hesitancy in the drop of vaccination coverage in Brazil? / Qual a importância da hesitação vacinal na queda das coberturas vacinais no Brasil?

ABSTRACT The successful Programa Nacional de Imunizações do Brasil (Brazilian National Immunization Program) has been experiencing a major challenge with regard to vaccination coverage for children, which has been dropping. Several aspects are related, but certainly vaccine hesitancy has been strengthening itself as one of the main concerns of Brazilian public administrators and researchers. Vaccine hesitancy is the delay in acceptance or refusal despite having the recommended vaccines available in health services, being a phenomenon that varies over time, over location and over types of vaccines. Hesitant individuals are between the two poles of total acceptance and refusal of vaccination. Vaccine hesitancy is nothing new in European and North-American countries, and even in Brazil, it has been studied even if under another name. The drop of vaccination coverage observed from 2016 on reiterates the relevance of the theme, which must be better understood through scientific research.

RESUMO O exitoso Programa Nacional de Imunizações do Brasil tem vivenciado grande desafio com relação às coberturas vacinais infantis, que têm apresentado queda. Diversos aspectos estão relacionados, mas certamente a hesitação vacinal vem se fortalecendo como uma das principais preocupações dos gestores e pesquisadores brasileiros. Hesitação vacinal é o atraso em aceitar ou a recusa das vacinas recomendadas quando elas estão disponíveis nos serviços de saúde, sendo um fenômeno que varia ao longo do tempo, do local e dos tipos de vacinas. Indivíduos hesitantes situam-se entre os dois polos de aceitação e recusa total da vacinação. A hesitação vacinal não é novidade em países europeus e norte-americanos e, mesmo no Brasil, ela já vem sendo estudada ainda que sob outra denominação. A queda das coberturas vacinais observadas a partir de 2016 reitera a relevância do tema, que deve ser mais bem compreendido por meio de investigações científicas.

Plano de Erradicação da Poliomielite: estratégia no Brasil / Plan for the Eradication of Poliomyelitis: strategy in Brazil

Segundo a resolução WHA41.28,da Assembleia Mundial da Saúde realizada em 1988, iniciou-se o programa global de erradicação da poliomielite. Vários progressos têm sido alcançados como a inexistência de casos pelo poliovírus selvagem tipo 2 desde 1999 e pelo poliovírus selvagem tipo3 desde 11 de novembro de 20121. Outro momento marcante para a erradicação global da poliomielite foi 68ª Assembleia Mundial da Saúde realizada no período de 18 a 26 de maio de 2015 em Genebra, que reuniu autoridades sanitárias de 194 países. Neste evento, foi definida a Resolução WHA68.3, na qual constam novos acordos sobre a erradicação global da poliomielite, reforçando que a erradicação só poderá ser alcançada por meio do compromisso global, que foi endossado pelos países membros2. Os acordos definidos na Resolução WHA68.3são frutos das conclusões da reunião do Grupo Consultor Estratégico de Especialistas (SAGE) da Organização Mundial da Saúde (OMS), realizada no período 21 a 23 de outubro de 2014. Destacaram que os preparativos para a retirada do componente tipo 2 da vacina poliomielite 1, 2 e 3 (atenuada), chamada de Vacina trivalente atenuada contra poliomielite soro tipos 1,2,3 (VOPt), encontram-se em processo e devem ser concluídos até abril de 2016. A partir desse período, todos os países deverão empreender esforços para a substituição da vacina trivalente pela vacina poliomielite 1 e 3 (atenuada), conhecida como Vacina atenuada bivalente soro tipo 1 e 3 contra poliomielite (VOPb), que continuará a proteger contra o poliovírus tipo 1 e 3. A partir dessa retirada, os fabricantes deixarão de fornecer a vacina trivalente e os países não poderão de utilizá-la em seus programas de imunização. Os paísesmembros incluindo o Brasil, na 68ª Assembleia Mundial de Saúde,endossaram o compromisso internacional de...

Inactivated Poliovirus Vaccine Campaign in Kenya: Lessons Learned

Despite being free of polio since 2006 Kenya has suffered a number of wild poliovirus outbreaks in the subsequent years. In December 2013; in response to one such outbreak in Dadaab; inactivated poliovirus vaccine (IPV) was co-administered with oral poliovirus vaccine as a more effective measure in closing immunity gaps. A five-day vaccination campaign was staged followed by a vaccination coverage survey in the refugee camps of Dadaab and the surrounding host communities. A variety of operational challenges were faced - the number of health facilities; outreach sessions; human resources and cold chain logistics were suboptimal in the campaign area with its scattered population and nomadic living pattern. However; despite the challenges; the survey showed that excellent coverage was achieved. Lessons learned evidence that IPV can be administered in similar geographical settings; and that systematically tailored training; timely and capacity-based operational/micro-planning; and evidence-based communication and social mobilization can make for successful outcomes

Genetic Characteristics of Type 2 Vaccine-derived Poliovirus in Shanxi Province (China) in 2014 / 病毒学报

The World Health Organization redefined the type 2 vaccine-derived poliovirus (VDPV) in 2010. To study the genetic characteristics and evolution of type 2 VDPV under this new definition, we conducted genome sequencing and analyses of type 2 VDPVs isolated from one patient with acute flaccid paralysis in Shanxi province (China) in 2014. Nucleotide sequencing revealed that the full-length of type 2 VDPV is 7439 bases encoding 2207 amino acids with no insertion or deletion of nucleotides compared with Sabin2. One nucleotide substitution identified as a key determinant of the attenuated phenotype of the Sabin 2 strain (A-G reversion at nucleotide nt 481 in the 5-end of the untranslated region) had reverted in the Shanxi type 2 VDPV. The other known key determinant of the attenuated phenotype of the Sabin 2 strain (U-->C reversion at nt2909 in the VP1 coding region that caused a Ile143Thr substitution in VP1) had not reverted in the Shanxi VDPV. The Shanxi type 2 VDPV was S2/S1 recombinant, the crossover site of which mapped to the 3-end of the 3D region (between nt 6247 and nt 6281). A phylogentic tree based on the VP1 coding region showed that evolution of the Shanxi type 2 VDPV was independent of other type 2 VDPVs detected worldwide. We estimated that the strain circulated for approximately = 11 months in the population according to the known evolution rate. The present study confirmed that the Chinese Polio Laboratory Network could discover the VDPV promptly and that it played an important part in maintenance of a polio-free China.

Investigation of a Patient with Pre-vaccine-derived Poliovirus in Shandong Province, China / 病毒学报

To analyze the genetic characteristics of a polio-I highly variant vaccine recombinant virus in Shandong Province (China) in 2011 and to identify isolates from healthy contacts, two stool specimens from one patient with acute flaccid paralysis (AFP) and 40 stool specimens from his contacts were collected for virus isolation. The complete genome of poliovirus and VP1 coding region of the non-polio enterovirus were sequenced. Homologous comparison and phylogenetic analyses based on VP1 sequences were undertaken among coxsackievirus (CV) B1, CV-B3 isolates, and those in GenBank. One poliovirus (P1/11186), CV-A4 and CV-A8 were isolated from the AFP patient; one CV-A2, Echovirus 3 (E-3), E-12 and E-14, ten CV-B1, and five CV-B3 strains were isolated from his contacts. These results led us to believe that there may be a human enterovirus epidemic in this area, and that surveillance must be enhanced. P1/11186 was a type-1 vaccine-related poliovirus; it combined with type-2 and type-3 polioviruses in 2A and 3A regions, respectively. There were 25 nucleotide mutations with 9 amino-acid alterations in the entire genome. There were 8 nucleotide mutations with 5 amino-acid alterations in the VP1 region compared with the corresponding Sabin strains. Homology analyses suggested that the ten CV-B1 isolates had 97.0%-100% nucleotide and 98.9%-100% amino-acid identities with each other, as well as 92.6%-100% nucleotide and 99.2%-100% amino-acid identities among the five CV-B3 isolates. Phylogenetic analyses on the complete sequences of VP1 among CV-B1 and CV-B3 isolates showed that Shandong strains, together with strains from other provinces in China, had a close relationship and belonged to the same group.

Infant polio immunization; time series modeling towards coverage in Pakistan

Poliomyelitis is a highly infectious disease but preventable by effective vaccines. Children under five year of age affected by this disease as a result a permanent paralysis. To uncover the trend of infant polio immunization coverage through modeling is a significant concern to formulate an adequate vaccination strategies and program after the outbreak of new cases of polio in a recent year in Pakistan. The reported data of monthly infant polio immunization coverage to National Institute of Health, Islamabad, Pakistan from January 2008 to July 2013 for the present study has been taken from Pakistan bureau of statistics with total time series entities 67. National Institute of Health, Islamabad took the record of per month number of doses administered [0-11 months] children by the registered health centre in pakistan. January 2008 - July 2013. Pakistan bureau of statistics [Statistics House]. A set of various short term time series forecasting models namely Box-Jenkins, single moving average, double moving average, single parameter exponential smoothing, brown, Holts and winter models were carried out to expose the infant polio immunization coverage trend. Among the several forecasting models ARIMA models are chosen due to lower measure of forecast errors namely root mean square error [RMSE], mean absolute error [MAE] and mean absolute percentage error [MAPE]. ARIMA [2,1,1], ARIMA [1,0,2], ARIMA [0,1,2] and ARIMA [2,1,1] models are established as an adequate models for the prediction of OPV-0, OPV-1, OPV-2 and OPV-3 respectively. With the exception of OPV-1 the infant polio immunization coverage is expected to rise in Pakistan

El camino hacia la erradicación de la poliomielitis a través de la Organización Panamericana de la Salud / The road to polio eradication via the Pan American Health Organization

OBJETIVO: Reconstruir las actividades del Programa Panamericano de Erradicación de la Poliomielitis, a través de los documentos generados por la Organización Panamericana de la Salud (OPS) entre 1985 y 1994 MÉTODOS: Se utilizaron, como fuentes primarias de información, los documentos sobre erradicación de la poliomielitis generados entre 1985 y 1994, a través del portal de acceso de publicaciones de la página oficial de la OPS. Se estableció una clasificación de los documentos y se estudiaron sus contenidos, contextualizándolos en el marco de la historia de salud pública internacional RESULTADOS: Se encontraron 260 documentos clasificados en boletines, resoluciones, artículos y libros. En 1985, la OPS puso en marcha la iniciativa de erradicación de la transmisión del poliovirus salvaje en las Américas para 1990. Se establecieron comisiones nacionales, un grupo técnico asesor, reuniones interfronteras y otros mecanismos de coordinación. El seguimiento de las acciones de erradicación por parte de la Comisión Internacional para la Certificación de la Erradicación de la Poliomielitis se llevó a cabo a través de cinco indicadores; obteniéndose la certificación oficial para la Región de las Américas en 1994 CONCLUSIONES: El camino que condujo a la erradicación de la poliomielitis en la Región de las Américas estuvo condicionado por las diferentes circunstancias políticas, sociales y económicas de los diferentes países integrantes y no estuvo exento de problemas. Aun así, se lograron importantes acuerdos de colaboración e intercambio de experiencias y recursos, que condujeron a alcanzar la meta final antes que otras regiones. La OPS jugó un papel central y lideró todo el proceso.

OBJECTIVE: Reconstruct the activities of the Pan American Poliomyelitis Eradication Program, through documents produced by the Pan American Health Organization (PAHO) from 1985 to 1994 METHODS: Documents on polio eradication produced from 1985 to 1994, obtained through the publications portal at the official PAHO website, were used as primary sources of information. Documents were categorized by type and their contents studied, revealing their context in the framework of the history of international public health RESULTS: Two hundred sixty documents were found and categorized as bulletins, resolutions, articles, and books. In 1985, PAHO implemented an initiative to eradicate transmission of wild poliovirus in the Americas by 1990. National commissions, a Technical Advisory Group, cross-border meetings, and other coordination mechanisms were established. Eradication activities were monitored by the International Commission for the Certification of Polio Eradication, using five indicators. The Region of the Americas was officially certified in 1994 CONCLUSIONS: The road to polio eradication in the Region of the Americas was affected by different political, social, and economic circumstances in the different member countries and was not problem-free. Nonetheless, important collaboration agreements were reached and experiences and resources were shared. This led to achieving the final goal before other regions. PAHO played a key role and spearheaded the entire process.

Knowledge, attitude and practice of polio prevention among people in Khyber Pakhtunkhwa

To assess the knowledge, attitude and practice of polio among people in Khyber Pakhtun Khwa and to recommand measures in order to improve the awareness of disease. Descriptive cross sectional study. This study was conducted at CMH nowshera, CMH mardan and Kohat General Hospital from March to June 2013. Persons presenting for consultation to tertiary care hospitals at medical reception rooms were approached by convenience sampling. Structured questionnaire was developed and data was collected by interviews. The findings of the study revealed that out of 296 persons participated in study 57.4% were males while 42.2% were females. They were residents of Mardan, Nowshera, Kohat and Swabi districts of Khyber Pakhtunkhwa. Persons who believed that vaccine is prohibited in religion were 13.9%, 81.1% persons knew about polio disease and 84.5% persons believed that disease could be prevented by giving vaccines to children. Persons who gave vaccine to their children were 88.9% and 66.9% also knew the schedule of the vaccine. Pressure groups which included tribal elders' stopped 19.3%people from giving vaccine to their children and for 11.1% persons the facility of giving vaccine was not available. Persons who believed that Polio can cause infertility were 11.5% and 20.9% believed that Polio Vaccine cannot prevent Polio disease. Persons who have seen patient of polio were 38.9% and 88.5% persons wanted to eradicate disease from Pakistan. The results of the study revealed that people have adequate knowledge about polio and wanted to eradicate it from pakistan by participating in vaccination activities but still there are few people who believe that polio vaccine cannot prevent disease resulting in failure to administer vaccine for their children

An investigation on a case of hand-foot-mouth disease caused by coxsackie-virus A6 associated with a vaccine-derived poliovirus co-infection / 中华流行病学杂志

<p><b>OBJECTIVE</b>To identify the pathogen and characteristics on a case of hand-foot-mouth disease (HFMD) caused by coxsackie-virus A6 (CA6) associated with vaccine-derived poliovirus (VDPV) co-infection.</p><p><b>METHODS</b>Field epidemiological study at the epidemic area was conducted and 16 stool samples including from the patient and close contacts were collected for isolation and identification of the enterovirus (EV). 21 stool samples from patients diagnosed as HFMD were collected in the same hospital at the same month to detect CA16,EV71, CA6 and PV by real-time RT-PCR or RT-PCR. The VP1 gene of the CA6 was amplified by RT-PCR and PCR products were sequenced and analyzed.</p><p><b>RESULTS</b>The patient showed only HFMD symptoms, but no symptoms related to acute flaccid paralysis (AFP). No EVs were isolated from 16 samples collected from the patient and close contacts. And no AFP cases were found by an active search. A total of 21 samples from patients diagnosed as HFMD were collected in the same hospital at the same month and 4 were found to be EV71, 2 were CA16 and 15 (include the patient)were CA6. Only this patient was found to have had VDPV II infection. The CA6 VP1 gene was amplified from the HFMD patient and 9 other cases from the same hospital at the same month. Nucleotide sequences of the VP1 gene among the 9 strains shared 98.9%-100.0% in homology and 96.0%-100.0% in the deduced amino acid sequences. Phylogenetic analysis of the VP1 sequences categorized the 9 strains into the same branch. There were 6 nucleotides changes including U2909A between the VP1 region of the VDPV strain of the case and Sabin II. Results from phylogenetic analysis on the VP1 sequences indicated that the VDPV strain of the case was different from other VDPVs strains isolated in the world.</p><p><b>CONCLUSION</b>This case was a HFMD which caused by CA6 co-infection with VDPV II and the VDPV was newly discovered. HFMD symptoms of the case were caused by CA6. The reason why this case did not have AFP symptoms was probably due the protective effect of IPV vaccine. No AFP cases were found by the active search for AFP cases conducted in the area, which indicated that VDPV did not cause virus circulation in this area.</p>

Formation and identification of virus-like particles of poliovirus type I / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To establish a method to produce virus-like particles (VLP) of poliovirus type I in Saccharomy cescerevisiae to develop potential novel recombinant vaccine against poliovirus type 1.</p><p><b>METHODS</b>The genes of P1 and 3CD of poliovirus type I were optimized, synthesized and inserted into expression vector, which was further transfected into Saccharomy cescerevisiae. The extracts of yeast cells were purified by CsCl density gradient centrifugation after induction and cell lysis.</p><p><b>RESULTS</b>Electrophoresis and sequencing analyses showed that the genes P1 and 3CD of poliovirus type I were successfully inserted into expression vector and encode a protein whose amino acid sequences were identical with wide-type genes of poliovirus type I. Electronic microscopy analysis showed that the VLPs of poliovirus type I could be efficiently formed in Saccharomy cescerevisiae.</p><p><b>CONCLUSION</b>The VLPs of poliovirus type I could be efficiently produced by co-expression of P1 and 3CD genes in Saccharomy cescerevisiae.</p>

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%

Coverage and causes of non immunization in national immunization days for polio; a consumer and provider perspective study in Peshawar

Polio is a viral disease that may cause paralysis and infant death. Despite ongoing efforts, polio has not been eradicated from Pakistan. The purpose of this survey is to estimate the coverage of polio vaccine during National Immunization Days and to determine the factors associated with lack of immunization. A Cross-sectional survey was conducted in Peshawar, Pakistan, from 1[st] June to 9[th] June 2010. Confidence level of 95% and confidence interval of 4 was used to derive the sample size [for a population more than 20,000]. Parents of 600 children under 5 years were asked about immunization during NIDs of January - May 2010 [5 NIDs]. Questions regarding demographics, income, education, occupation, accessibility to health centers and frequency of visits from health workers was inquired. Knowledge and views on immunization were also asked. 40 health personnel involved in immunization were also interviewed and they were asked about hurdles faced in immunization. 83.7% children were vaccinated in all National Immunization Days, while 94.7% had at least, taken polio vaccine once. 5.3% had not taken polio vaccine during National immunization Days of 2010. Main reasons for not vaccinating were; Vaccinator absent/not visiting home/vaccine not available [63.36%], no awareness [17.4%], Child ill [5.8%], family problem/mother busy [3.3%] and wrong ideas/sterility [3.3%]. Many health personnel [32.5%] considered lack of awareness among people and low accessibility to vaccine as the main hurdles in immunization, besides the poor salaries and incentives. Polio vaccination during National Immunization Days 2010 was a partial success because some pockets of poor children and afghan refugees were poorly vaccinated. In order to eradicate polio, they must be vaccinated