Pediatric and adolescent COVID-19 vaccination side effects: A retrospective cohort study of the Iranian teenage group in 2021.

To determine the safety and efficacy profile of teenager COVID-19 vaccination. In this retrospective cohort study, contact numbers of parents of teenagers under 18 years of age referred to a teenager vaccination centers in Tehran-Iran to receive the corona vaccine were collected, and the following information was obtained via the phones: demographic information, type of vaccine, and the number of doses received, as well as additional information like complications and required treatments. Eleven thousand forty-two subjects aged 10-18 years, mean age 14.55 ± 1.83 year including 5374 boys and 5768 girls were investigated. 88.1% received the Sinopharm and 11.9% the Soberana vaccine. General side effects, including fatigue, fever and chills, injection site pain and dizziness, and so forth happened in 2978 cases; 7421 children presented with at least one general or organ-specific side effect following vaccination, including potentially critical side effects, such as vascular injuries, respiratory complication, and so forth. 0.1% of the subject needed hospital admission. The breakthrough infection happened in 200 individuals. Our study shows that Sinopharm and Soberana (PastoCoVac) COVID-19 vaccines are generally safe with no serious side effects in less than 18 years old. COVID-19 infection and reinfection can occur after vaccination, but the incidence is actually tolerable and significantly lower than in the unvaccinated group.

Prospects for liver fluke vaccines.

Fasciola spp., Opisthorchis spp. and Clonorchis sinensis are common liver flukes that can cause a variety of diseases, mainly cholangiocarcinoma induced by clonorchiasis and liver damage and associated pathology induced by fascioliasis. Because these trematodes are parasites of humans and domestic animals, they have greatly affected the economy of agricultural industries and public health worldwide. Due to the emergence of drug resistance and the living habits of flukes, among other reasons, a possibility of reinfection remains even when antiparasitic drugs are used. Therefore, developing a safe, efficient and cost-effective vaccine against trematodes is an important goal. Here, we briefly describe the progress in the development of vaccines against liver flukes. Related innovations may provide effective protection against these helminths and the diseases that they cause.

Review: Vaccine Myth-Buster - Cleaning Up With Prejudices and Dangerous Misinformation.

Although vaccines have already saved and will continue to save millions of lives, they are under attack. Vaccine safety is the main target of criticism. The rapid distribution of false information, or even conspiracy theories on the internet has tremendously favored vaccine hesitancy. The World Health Organization (WHO) named vaccine hesitancy one of the top ten threats to global health in 2019. Parents and patients have several concerns about vaccine safety, of which the ubiquitous anxieties include inactivating agents, adjuvants, preservatives, or new technologies such as genetic vaccines. In general, increasing doubts concerning side effects have been observed, which may lead to an increasing mistrust of scientific results and thus, the scientific method. Hence, this review targets five topics concerning vaccines and reviews current scientific publications in order to summarize the available information refuting conspiracy theories and myths about vaccination. The topics have been selected based on the author's personal perception of the most frequently occurring safety controversies: the inactivation agent formaldehyde, the adjuvant aluminum, the preservative mercury, the mistakenly-drawn correlation between vaccines and autism and genetic vaccines. The scientific literature shows that vaccine safety is constantly studied. Furthermore, the literature does not support the allegations that vaccines may cause a serious threat to general human life. The author suggests that more researchers explaining their research ideas, methods and results publicly could strengthen the general confidence in science. In general, vaccines present one of the safest and most cost-effective medications and none of the targeted topics raised serious health concerns.

Future considerations for the mRNA-lipid nanoparticle vaccine platform.

Vaccines based on mRNA-containing lipid nanoparticles (LNPs) pioneered by Katalin Karikó and Drew Weissman at the University of Pennsylvania are a promising new vaccine platform used by two of the leading vaccines against coronavirus disease in 2019 (COVID-19). However, there are many questions regarding their mechanism of action in humans that remain unanswered. Here we consider the immunological features of LNP components and off-target effects of the mRNA, both of which could increase the risk of side effects. We suggest ways to mitigate these potential risks by harnessing dendritic cell (DC) biology.

Anti-tick and pathogen transmission blocking vaccines.

Ticks and tick-borne diseases are a challenge for medical and veterinary public health and often controlled through the use of repellents and acaricides. Research on vaccination strategies to protect humans, companion animals, and livestock from ticks and tick-transmitted pathogens has accelerated through the use of proteomic and transcriptomic analyses. Comparative analyses of unfed versus engorged and uninfected versus infected ticks have provided valuable insights into candidates for anti-tick and pathogen transmission blocking vaccines. An intricate interplay between tick saliva and the host's immune system has revealed potential antigens to be used in vaccination strategies. Immunization of hosts with targeted anti-tick vaccines would ideally lead to a reduction in tick numbers and prevent transmission of tick-borne pathogens. Comprehensive control of tick-borne diseases would come from successful anti-tick vaccination, vaccination preventing transmission of tick-borne diseases or a combination. Due to the close interaction with wildlife and ticks, with wildlife reservoirs enabling propagation of pathogens between ticks, the vaccination of these reservoirs is an attractive target to reduce human contact with ticks and tick-borne diseases through a one-health approach. Wildlife vaccination presents formulation and regulatory challenges which should be considered early in the development of reservoir-targeted vaccines.

Vaccinations in Patients with Rheumatic Disease: Consider Disease and Therapy.

Patients with rheumatic diseases are susceptible to infections due to their underlying disease states as well as from immunosuppressive medications, highlighting the importance of vaccination, these same factors also pose challenges to vaccine efficacy, safety, and uptake. This article reviews the impact of immunosuppressive therapies and rheumatic disease on vaccine efficacy in this vulnerable patient population as well as discusses best practices.

Resumen de los avances de la vacuna frente a SARS-CoV-2 / Summary on advances in the development of vaccines against COVID-19

Nos encontramos en plena carrera científica para frenar la expansión del SARS-CoV-2. Una de las formas más prometedoras es desarrollar una vacuna segura y eficaz, que permita la inmunización de la mayor parte de la población. En este sentido, son numerosos los estudios que se están llevando a cabo. No obstante, la información que nos llega puede ser abrumadora, por eso este artículo pretende esclarecer la situación. Actualmente existen más de 60 prototipos de vacunas frente a COVID-19 sometidos a ensayos clínicos y más de 170 prototipos en fases preclínicas. A pesar de que las propuestas actuales cubren casi todas las formas de investigación, las plataformas más prometedoras son los ácidos nucleicos, como el mRNA, que destaca por su alta potencia, cortos ciclos de producción, bajo coste y administración segura. De hecho, son el soporte de las dos vacunas aprobadas para su comercialización en Europa, Comirnaty(R) y la va-cuna de Moderna. Aunque dispongamos de vacunas seguras y efectivas comercializadas, los laboratorios deberán ampliar la información acerca del tiempo que permanece la protección, la prevención de casos graves, si previene infecciones asintomáticas, así como información en personas inmunodeprimidas, niños y embarazadas. No obstante, es importante considerar que la obtención de una vacuna no supone el control inmediato de la pandemia, sino más bien, un proceso gradual, puesto que se necesita un determinado porcentaje de población vacunada para frenar el contagio comunitario. Por eso, es de vital importancia cumplir las medidas higiénico-sanitarias y seguir siendo prudentes

We are attending a scientific race to stop the expansion of SARS-CoV-2. One of the most promising ways is to develop a safe and effective vaccine that will allow the majority of the population to be immunized. In this sense, numerous studies are in progress. However, the information that reaches us can be overwhelming, so this article aims to clarify the situation. Currently there are more than 60 prototypes of vaccines against COVID-19 submitted to clinical trials and more than 170 prototypes in preclinical phases. Although current proposals cover almost all forms of research, the most promising platforms are nucleic acids, such as mRNA, which stands out for its high potency, short production cycles, low cost and safe administration. In fact, they are the base for the two vaccines approved for commercialization in Europe, Comirnaty (R) and the Moderna vaccine. Even though we have safe and effective vaccines commercialized, laboratories should expand the information about the time that protection remains, the prevention of serious cases, if it prevents asymptomatic infections, as well as information in immuno-suppressed people, children and pregnant women. However, it is important to consider that obtaining a vaccine does not imply immediate control of the pandemic, but rather, a gradual process, since a certain percentage of the vaccinated population is needed to stop the community contagion. Therefore, it is of vital importance to comply with sanitary hygiene measures and to remain prudent

Y a final de año llegó la esperanza / At the end of the year, hope came

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Designing the Next Generation of Vaccines: Relevance for Future Pandemics.

The development of vaccines is one of the greatest medical interventions in the history of global infectious diseases and has contributed to the annual saving of at least 2 to 3 million lives worldwide. However, many diseases are not preventable through currently available vaccines, and the potential of modulating the immune response during vaccination has not been fully exploited. The first golden age of vaccines was based on the germ theory and the use of live, attenuated, inactivated pathogens or toxins. New strategies and formulations (e.g., adjuvants) with an immunomodulatory capacity to enhance the protective qualities and duration of vaccines have been incompletely exploited. These strategies can prevent disease and improve protection against infectious diseases, modulate the course of some noncommunicable diseases, and increase the immune responses of patients at a high risk of infection, such as the elderly or immunocompromised patients. In this minireview, we focus on how metabolic and epigenetic modulators can amplify and enhance the function of immunity in a given vaccine. We propose the term "amplifier" for such additives, and we pose that future vaccines will have three components: antigen, adjuvant, and amplifier.

How vaccines work: immune effector mechanisms and designer vaccines.

Introduction: Three major advances have led to increase in length and quality of human life: increased food production, improved sanitation and induction of specific adaptive immune responses to infectious agents (vaccination). Which has had the most impact is subject to debate. The number and variety of infections agents and the mechanisms that they have evolved to allow them to colonize humans remained mysterious and confusing until the last 50 years. Since then science has developed complex and largely successful ways to immunize against many of these infections.Areas covered: Six specific immune defense mechanisms have been identified. neutralization, cytolytic, immune complex, anaphylactic, T-cytotoxicity, and delayed hypersensitivity. The role of each of these immune effector mechanisms in immune responses induced by vaccination against specific infectious agents is the subject of this review.Expertopinion: In the past development of specific vaccines for infections agents was largely by trial and error. With an understanding of the natural history of an infection and the effective immune response to it, one can select the method of vaccination that will elicit the appropriate immune effector mechanisms (designer vaccines). These may act to prevent infection (prevention) or eliminate an established on ongoing infection (therapeutic).Literature search: The primary literature source is Pub Med. Secondary source is Wikipedia.

Progress, challenges and opportunities in fish vaccine development.

In 2014 the contribution of aquaculture to supply food for human consumption overtook wild-caught fish for the first time. Despite improvements in the aquaculture industry, it has been estimated that as much as 10% of all cultured aquatic animals are lost because of infectious diseases, amounting to >10 billion USD in losses annually on a global scale. Vaccination to prevent disease is used routinely in finfish aquaculture, especially for Atlantic salmon (Salmo salar), while in a limited capacity (or not at all) in many other fish species due to lack of vaccines, poor performance or cost. There has, nevertheless, been impressive progress in fish vaccine development over the last 4 decades with 24 licenced fish vaccines now commercially available for use in a variety of fish species. These comprise whole killed, peptide subunit, recombinant protein, DNA and live attenuated vaccines. Challenges do, however, still exist as the majority of commercial vaccines are killed whole cell pathogen preparations administered by intraperitoneal injection. This may not be the optimal route to deliver some vaccines, but lack of effective adjuvants and basic knowledge on immune response has hindered progress in the development of mucosal vaccines. The cost of injecting fish may also be prohibitive in some countries leading to disease treatment (e.g. with antibiotics) rather than using preventative measures. It is important that these issues are addressed as the industry continues to grow globally. Exciting opportunities exist for rapid development of fish vaccines in the future, with continued reduction in cost of technologies (e.g. of whole genome sequencing), regulations changing (e.g. DNA vaccines can now authorised in Europe), the introduction of novel antigen expression and delivery systems (such as virus-like particles, VLPs), development of novel adjuvants and advancements in the elucidation of basic mechanisms of mucosal immunity. Development of effective mucosal vaccines and optimisation of their delivery will facilitate novel vaccine development, and enable the aquaculture industries in LMIC to use vaccination routinely in the future. In addition, effective use of emergency (autogenous) vaccines will assist in tackling emerging disease challenges.

Imperfect vaccine and hysteresis.

Addressing vaccine compliance problems is of particular relevance and significance to public health. Despite resurgence of vaccine-preventable diseases and public awareness of vaccine importance, why is it so challenging to boost population vaccination coverage to desired levels especially in the wake of declining vaccine uptake? To understand this puzzling phenomenon, here we study how social imitation dynamics of vaccination can be impacted by the presence of imperfect vaccine, which only confers partial protection against the disease. Besides weighing the perceived cost of vaccination with the risk of infection, the effectiveness of vaccination is also an important factor driving vaccination decisions. We discover that there can exist multiple stable vaccination equilibria if vaccine efficacy is below a certain threshold. Furthermore, our bifurcation analysis reveals the occurrence of hysteresis loops of vaccination rate with respect to changes in the perceived vaccination cost as well as in the vaccination effectiveness. Moreover, we find that hysteresis is more likely to arise in spatial populations than in well-mixed populations, even for parameter choices that do not allow for bifurcation in the latter. Our work shows that hysteresis can appear as an unprecedented roadblock for the recovery of vaccination uptake, thereby helping explain the persistence of vaccine compliance problem.

Knowledge and practices regarding infant vaccination: results of a survey of French physicians.

A prospective, observational, survey of pediatricians and general practitioners (GPs) was conducted to assess pediatric vaccination knowledge and practices. The survey was distributed by email to 1069 pediatricians and 1700 GPs and completed by 151 pediatricians (14.1%) and 201 GPs (11.8%). Knowledge of the vaccination calendar was very good (99% overall). Of the respondents, 98% were confident in vaccine efficacy. Eight-one percent of pediatricians and 62% of GPs agreed that recommended vaccinations should become obligatory; all prescribed hexavalent vaccines often or always. More pediatricians (88%) than GPs (75%) used anti-pyretics; the use of anesthetic cream/patches was similar in each group (79% and 75%, respectively). The ambience at vaccination was considered to be important by both groups, and was disturbed in 37% of cases. Seventy percent of pediatricians and 57% of GPs agreed that vaccine reconstitution (e.g., Hib pellet) is a complicating factor: overall, 28% reported occasionally omitting to reconstitute a pentavalent or hexavalent vaccine in error, and 60% reported having not fully reconstituted the vaccine. Almost all (93%) considered non-reconstitution as an important error.Conclusion: Overall, adherence to good vaccination practices was good, although errors in reconstitution were reported by physicians. These problems would be minimized by wider use of fully liquid vaccines. What is Known: • Pediatric vaccination schedules are crowded. • Good vaccination practices and the use of multivalent vaccines are essential to maintain good compliance to pediatric vaccination recommendations. What is New: • Overall good compliance to good vaccination practices by both pediatricians and GPs in France. • Omission of pentavalent or hexavalent vaccine reconstitution of Hib pellet and incomplete reconstitution reported by pediatricians/GPs. Awareness of pediatricians/GPs that omission and incomplete reconstitution are important errors.

Paediatric and adult bronchiectasis: Vaccination in prevention and management.

Bronchiectasis has received increased attention recently, including an emphasis on preventing infective exacerbations that are associated with disease progression and lung function decline. While there are several bacteria and viruses associated with bronchiectasis, licensed vaccines are only currently available for Streptococcus pneumoniae, Haemophilus influenzae (H. influenzae protein D as a conjugate in a pneumococcal vaccine), Mycobacterium tuberculosis, Bordetella pertussis and influenza virus. The evidence for the efficacy and effectiveness of these vaccines in both preventing and managing bronchiectasis in children and adults is limited with the focus of most research being on other chronic lung disorders, such as chronic obstructive pulmonary diseases, asthma and cystic fibrosis. We review the existing evidence for these vaccines in bronchiectasis and highlight the existing gaps in knowledge. High-quality experimental and non-experimental studies using current state-of-the-art microbiological methods and validated, standardised case definitions are needed across the depth and breadth of the vaccine development pathway.

Use of electronic immunization registry in the surveillance of adverse events following immunization.

OBJECTIVE: To describe adverse events following vaccination (AEFV) of children under two years old and analyze trend of this events from 2000 to 2013, in the city of Araraquara (SP), Brazil. METHODS: This is a descriptive study conducted with data of the passive surveillance system of AEFV that is available in the electronic immunization registry (EIR) of the computerized medical record of the municipal health service (Juarez System). The study variables were: age, gender, vaccine, dose, clinical manifestations and hospitalization. We estimated rates using AEFV as numerator and administered doses of vaccines as denominator. The surveillance sensitivity was estimated by applying the method proposed by the Centers for Disease Control and Prevention. We used Prais-Winsten regression with a significance level of 5.0%. RESULTS: The average annual rate of AEFV was 11.3/10,000 administered doses, however without a trend in the study period (p=0.491). Most cases occurred after the first dose (41.7%) and among children under one year of age (72.6%). Vaccines with pertussis component, yellow fever and measles-mumps-rubella were the most reactogenic. We highlighted the rates of hypotonic-hyporesponsive episodes and convulsion that were 4.1/10,000 and 1.5/10,000 doses of vaccines with pertussis component, respectively, most frequently in the first dose; 60,0% of cases presented symptoms in the first 24 hours after vaccination, however, 18.6% showed after 96 hours. The sensitivity of surveillance was 71.9% and 78.9% for hypotonic-hyporesponsive episodes and convulsion, respectively. CONCLUSIONS: The EIR-based AEFV surveillance system proved to be useful and highly sensitive to describe the safety profile of vaccines in a medium-sized city. It was also shown that the significant increase of the vaccines included in the basic vaccination schedule in childhood in the last decade did not alter the high safety standard of the National Immunization Program.

Adaptación de los calendarios de vacunación en población pediátrica que ha recibido quimioterapia / Adapting immunisation schedules for children undergoing chemotherapy

Introducción: Los niños que son sometidos a quimioterapia en el contexto de un cáncer presentan necesidades especiales de vacunación una vez finalizado el tratamiento. El objetivo de este trabajo es evaluar la adaptación de los calendarios de vacunación posquimioterapia en una población pediátrica. Método: Estudio observacional de una cohorte retrospectiva. Se incluyeron todos los niños entre 0 y 14 años que recibieron quimioterapia en un hospital de tercer nivel entre 2009 y 2015. Se aplicaron criterios de inclusión/exclusión. Se siguieron las indicaciones oficiales del Comité Asesor de Vacunas de la Asociación Española de Pediatría para estas situaciones. Se consultó el registro de vacunación de Atención Primaria y el de la Unidad de Vacunas del Servicio de Medicina Preventiva y Salud Pública del centro sanitario. Resultados: De los 99 niños que recibieron quimioterapia, se incluyeron en el estudio 51. El 70,6% fueron varones. El 54,9% padecían un tumor de órgano sólido y el 45,1% un tumor hematológico. El 70,6% tenía registrada alguna vacuna tras el tratamiento. Las vacunas administradas con mayor frecuencia fueron: difteria-tétanos-tosferina o difteria-tétanos (54,9%), meningococo C(41,2%) y la gripe estacional (39,2%). La tasa de adaptación de calendario posquimioterapia fue del 9,8%. La vacuna frente a neumococo conjugada 7v o 13v fue administrada en el 21,6% de los niños evaluados, sin embargo, solo se completó con polisacárida 23v en el 17,6% de los casos. Ninguno recibió vacunación frente a hepatitis A. No se encontraron diferencias estadísticamente significativas entre el cumplimiento del calendario y el tipo de tumor (p=0,066), el sexo (p=0,304) o la edad (p=0,342). Conclusión: Existe un importante margen de mejora en la adaptación de la vacunación posquimioterapia en niños con cáncer. La participación de los profesionales en programas de formación y la derivación de estos pacientes a las Unidades de Vacunas podría mejorar la tasa de adaptación garantizando una correcta inmunización en estos niños (AU)

Introduction: Children undergoing chemotherapy for cancer have special vaccination needs after completion of the treatment. The aim of this study was to evaluate the adaptation of post-chemotherapy vaccination schedules. Method: An observational study was performed on a retrospective cohort that included all children aged from 0 to 14 years, who completed chemotherapy in a tertiary hospital between 2009 and 2015. Inclusion and exclusion criteria were applied. Immunisation was administered in accordance with the guidelines of the Vaccine Advisory Committee of the Spanish Association of Paediatrics. Primary Care immunisation and clinical records of the Preventive Medicine and Public Health Department were reviewed. Results: Of the 99 children who had received chemotherapy, 51 (70.6% males) were included in the study. As regards the type of tumour, 54.9% had a solid organ tumour, and 45.1% had a haematological tumour. Post-chemotherapy immunisation was administered to 70.6%. The most common vaccines received were: diphtheria-tetanus-pertussis or diphtheria-tetanus (54.9%), meningococcus C (41.2%), and seasonal influenza (39.2%). The rate of adaptation of the immunisation schedule after chemotherapy was 9.8%. The pneumococcal conjugate vaccine against 7v or 13v was administered to 21.6% of study subjects. However, only 17.6% received polysaccharide 23v. None received vaccination against hepatitis A. No statistically significant differences were observed between adherence to immunisation schedules and type of tumour (P=.066), gender (P=.304), or age (P=.342). Conclusion: Post-chemotherapy immunisation of children with cancer is poor. The participation of health professionals in training programs and referral of paediatric cancer patients to Vaccine Units could improve the rate of schedule adaptation and proper immunisation of this population (AU)

Use of electronic immunization registry in the surveillance of adverse events following immunization / Uso de registro informatizado de imunização na vigilância de eventos adversos pós-vacina

ABSTRACT OBJECTIVE To describe adverse events following vaccination (AEFV) of children under two years old and analyze trend of this events from 2000 to 2013, in the city of Araraquara (SP), Brazil. METHODS This is a descriptive study conducted with data of the passive surveillance system of AEFV that is available in the electronic immunization registry (EIR) of the computerized medical record of the municipal health service (Juarez System). The study variables were: age, gender, vaccine, dose, clinical manifestations and hospitalization. We estimated rates using AEFV as numerator and administered doses of vaccines as denominator. The surveillance sensitivity was estimated by applying the method proposed by the Centers for Disease Control and Prevention. We used Prais-Winsten regression with a significance level of 5.0%. RESULTS The average annual rate of AEFV was 11.3/10,000 administered doses, however without a trend in the study period (p=0.491). Most cases occurred after the first dose (41.7%) and among children under one year of age (72.6%). Vaccines with pertussis component, yellow fever and measles-mumps-rubella were the most reactogenic. We highlighted the rates of hypotonic-hyporesponsive episodes and convulsion that were 4.1/10,000 and 1.5/10,000 doses of vaccines with pertussis component, respectively, most frequently in the first dose; 60,0% of cases presented symptoms in the first 24 hours after vaccination, however, 18.6% showed after 96 hours. The sensitivity of surveillance was 71.9% and 78.9% for hypotonic-hyporesponsive episodes and convulsion, respectively. CONCLUSIONS The EIR-based AEFV surveillance system proved to be useful and highly sensitive to describe the safety profile of vaccines in a medium-sized city. It was also shown that the significant increase of the vaccines included in the basic vaccination schedule in childhood in the last decade did not alter the high safety standard of the National Immunization Program.

RESUMO OBJETIVO Descrever os eventos adversos pós-vacina ocorridos em crianças com até dois anos de idade e analisar a tendência desses eventos, entre 2000 e 2013, em Araraquara, SP, Brasil. MÉTODOS Estudo descritivo com dados da vigilância passiva de eventos adversos pós-vacina, disponíveis no registro informatizado de imunização do prontuário eletrônico do serviço municipal de saúde (Sistema Juarez). As variáveis de estudo foram: idade, sexo, vacina, dose, manifestações clínicas e hospitalização. As taxas foram estimadas tomando-se os casos de eventos adversos pós-vacina como numerador e as doses aplicadas, como denominador. Estimou-se a sensibilidade da vigilância de eventos adversos pós-vacina aplicando-se o método proposto pelo Centers for Disease Control and Prevention. Para análise de tendência utilizou-se a regressão de Prais-Winsten, considerando o nível de significância de 5,0%. RESULTADOS A taxa anual média de eventos adversos pós-vacina foi de 11,3/10.000 doses aplicadas, porém, sem tendência no período estudado (p = 0,491). Houve predomínio de casos após a primeira dose (41,7%) e entre menores de um ano de idade (72,6%). As vacinas com componente pertussis, de febre amarela e de sarampo-caxumba-rubéola foram as mais reatogênicas. Destacou-se a frequência de episódio hipotônico hiporresponsivo e convulsão, com taxas de 4,1/10.000 e 1,5/10.000 doses de vacinas com componente pertussis, respectivamente, mais elevadas na primeira dose; 60,0% dos casos apresentaram sintomas nas primeiras 24 horas após a vacinação e 18,6% apresentaram-se após 96 horas. A sensibilidade da vigilância foi estimada em 71,9% e 78,9% para episódio hipotônico hiporresponsivo e convulsão, respectivamente. CONCLUSÕES O sistema de vigilância de eventos adversos pós-vacina com base no registro informatizado de imunização mostrou-se útil e dotado de elevada sensibilidade para descrever o perfil de segurança das vacinas em um município de médio porte. Adicionalmente, a expressiva ampliação, na última década, das vacinas incluídas no esquema básico de vacinação na infância não alterou o elevado padrão de segurança do Programa Nacional de Imunizações.