Delays in the vaccination of infants between 2 and 18 months of age: associated factors in Chile.

INTRODUCTION: Infant vaccination has significantly reduced the morbidity and mortality of transmittable diseases worldwide. Its coverage is high (85%); however, partial or suboptimal vaccination has been an important public health problem. This study aimed (1) to design and explore the psychometric features of a questionnaire to determine the reasons for this partial or suboptimal vaccination; and 2) to determine the factors associated with delaying Diphtheria, Tetanus, Poliomyelitis (DTaP) vaccination. MATERIAL AND METHODS: This study contained two parts. In Part One, a questionnaire was created by the research team and then validated by a committee of experts in the field and a group of parents. It included the following contents: sociodemographic variables, features of the vaccination services, history of vaccination, and attitudes and perceptions about vaccination. Part Two was a cross-sectional study, recruiting private and public healthcare centers to explore the psychometrics features of the instrument, performing exploratory factor analysis, and determining the associated factors with DTaP vaccination delay throughout multivariable regression models. RESULTS: Initially, six experts validated the questionnaire. For instance, on a scale of 1 to 5, the general evaluation of the questionnaire was ≥ 4 for all the experts. Additionally, five experts considered that most of the questions were easy to understand, and all thought the questionnaire had a clear and logical organization. The resulting questionnaire included the "Trust and positive attitude towards vaccination" scale, which had a good structure of items and internal consistency (α = 0.7918). Six healthcare centers were recruited in the second part of the study, and 715 people answered the questionnaire. Not being the mother who brings the child to the health center, having more than one child, and having a history of previous vaccination delays increased the risk of delaying vaccination. Attending the healthcare center for a reason other than only vaccination, obtaining information about vaccines from the Internet, and having higher trust and positive attitudes to vaccination reduced the risk of delay. CONCLUSIONS: First study during the pandemic to explore the role of different factors on the risk of DTaP vaccination delay in Latin America. The findings highlighted the importance of trust in the vaccination system. The instrument presented in this article may help the scientific community evaluate future interventions to increase trust and positive attitudes toward the vaccination process.

[Seasonal influenza campaign 2020 in the context of SARS-CoV-2 pandemic: an unprecedented public health experience in Chile]. / Campaña influenza 2020 en contexto de pandemia por SARS-CoV-2: una experiencia inédita de salud pública en Chile.

In Chile, the Immunization Department of the Ministry of Health has carried out the seasonal influenza vaccination campaign annually since 1982 in collaboration with the national health services, regional health offices, and primary health care centres. With the aim of preventing deaths and serious morbidity in high-risk groups and preserving the integrity of health services, the seasonal influenza campaign had been the largest implemented in Chile until 2020, since in 2021 the vaccination campaign against SARS-CoV-2 is expected to become the largest ever implemented. In response to local demographic and epidemiological changes, and taking into account the new scientific evidence on the safety and immunogenicity of vaccines, the influenza vaccines available in Chile would increase annually as a result of campaign planning. In 2020, the influenza campaign had to be re-planned while in progress due to the addition of new high-risk groups to be vaccinated in accordance with the SARS-CoV-2 pandemic health alert modification of March 6th, 2020. Over the course of three weeks, the Immunization Department managed to increase the doses of available influenza vaccines from 6,799,800 previously agreed upon to 8,480,325 and thus serve high-risk groups, guaranteeing their access to state funded influenza vaccination.

Campaña influenza 2020 en contexto de pandemia por SARS-CoV-2: una experiencia inédita de salud pública en Chile / Seasonal influenza campaign 2020 in the context of SARS-CoV-2 pandemic: an unprecedented public health experience in Chile

Resumen Desde 1982, cada año el Departamento de Inmunizaciones del Ministerio de Salud de Chile lleva a cabo la campaña de vacunación contra influenza junto con las Secretarías Regionales Ministeriales-SEREMI, Servicios de Salud y centros de atención primaria de salud. Con los objetivos de prevenir mortalidad y morbilidad grave en grupos de mayor riesgo y de preservar la integridad de los servicios de salud, hasta el 2020 las campañas de vacunación contra influenza serían las más grandes implementadas en Chile, para dar paso, el 2021, a la vacunación contra SARS-CoV-2. Obedeciendo a cambios demográficos y epidemiológicos locales y acogiendo los avances científicos sobre seguridad e inmunogenicidad de la vacuna, el incremento de las vacunas influenza disponibles en Chile forma parte de la planificación anual de la campaña. El 2020, sin embargo, la Campaña Influenza tuvo que ser re-planificada en curso como consecuencia de la incorporación de nuevos grupos a vacunar según dispuso la modificación de la alerta sanitaria por brote de SARS-CoV-2 del 6 de marzo de 2020. Así, de 6.799.800 de dosis, el Departamento de Inmunizaciones logró en menos de dos meses aumentar la disponibilidad a 8.480.325, y cumplir con el compromiso de garantizar el acceso de los grupos de riesgo al beneficio de la vacunación estatal gratuita.

Abstract In Chile, the Immunization Department of the Ministry of Health has carried out the seasonal influenza vaccination campaign annually since 1982 in collaboration with the national health services, regional health offices, and primary health care centres. With the aim of preventing deaths and serious morbidity in high-risk groups and preserving the integrity of health services, the seasonal influenza campaign had been the largest implemented in Chile until 2020, since in 2021 the vaccination campaign against SARS-CoV-2 is expected to become the largest ever implemented. In response to local demographic and epidemiological changes, and taking into account the new scientific evidence on the safety and immunogenicity of vaccines, the influenza vaccines available in Chile would increase annually as a result of campaign planning. In 2020, the influenza campaign had to be re-planned while in progress due to the addition of new high-risk groups to be vaccinated in accordance with the SARS-CoV-2 pandemic health alert modification of March 6th, 2020. Over the course of three weeks, the Immunization Department managed to increase the doses of available influenza vaccines from 6,799,800 previously agreed upon to 8,480,325 and thus serve high-risk groups, guaranteeing their access to state funded influenza vaccination.

Heterogeneity in influenza seasonality and vaccine effectiveness in Australia, Chile, New Zealand and South Africa: early estimates of the 2019 influenza season.

We compared 2019 influenza seasonality and vaccine effectiveness (VE) in four southern hemisphere countries: Australia, Chile, New Zealand and South Africa. Influenza seasons differed in timing, duration, intensity and predominant circulating viruses. VE estimates were also heterogeneous, with all-ages point estimates ranging from 7-70% (I2: 33%) for A(H1N1)pdm09, 4-57% (I2: 49%) for A(H3N2) and 29-66% (I2: 0%) for B. Caution should be applied when attempting to use southern hemisphere data to predict the northern hemisphere influenza season.