Spatial analysis of measles vaccination coverage in the State of São Paulo

Abstract

Background Measles is a contagious viral disease that seriously affects children. The measles vaccine is widely recommended in Brazil and in the world; however, the disease remains relevant for the health authorities. The aim of the present study was to evaluate first and second dose of measles vaccine coverage (VC) in the cities of São Paulo and its spatial dynamics between 2015 and 2020. Method: In this mixed-type ecological study, we used secondary, public domain data from 2015 to 2020, extracted from the Digital Information System of the National Immunization Program, Mortality Information System and the National Live Birth Information System. After calculating the VC, the following four categories were created: very low, low, adequate, and high, and the spatial autocorrelation of VC was analyzed using the Global and Local Moran’s statistics. Results A steady decline in adherence to the vaccination was observed, which dynamically worsened until 2020, with a high number of cities fitting the classification of ineffective coverage and being potentially harmful to the effectiveness of the immunization activities of their neighbors. Conclusion A direct neighborhood pattern was observed between the units with low vaccination coverage, which implied that the reduction in measles VC was somehow related to and negatively influenced by the geographic location and social culture of these areas.

Vaccination coverage and abandonment among children under two years old in Brazil: a time-series study

“… 13 In São Paulo, another Brazilian state, a number of researchers investigated VC specifically for measles, an infectious disease included in the country's basic vaccination schedule, and identified low VC between 2015 and 2020, with a greater reduction for the second dose of the vaccine against the disease. 14 Also in this regard, a research study that evaluated VC for agents that cause respiratory tract infections and the prevalence of childhood hospitalizations for these conditions in Brazil from 2015 to 2020 also found low VC and a significant increase in hospitalizations due to measles during the same period. 22 …”

“…6,7 Nonetheless, in recent years, several countries presented reductions in infant VC rates, such as Mexico, Colombia, Paraguay, Venezuela, Jordan and also Brazil, which may directly reflect on the increase in morbidity and mortality, as children's vulnerability is increased, especially in those under two years old. [7][8][9][10][11][12][13][14] The decrease in vaccination coverage is a process that preceded the COVID-19 pandemic, but has intensified during this period throughout the country. However, it is also influenced by access to vaccination services and by availability of products.…”

Imunização contra o sarampo: Uma revisão descritiva da literatura

“…O estudo de Pamplona et al (2023), que também se concentrou em dados do estado de São Paulo, buscando elucidar a dinâmica espacial entre 2015 e 2020, demonstrou que com o avanço dos anos houve declínio constante na adesão à vacinação, piorada no ano de 2020 e frente à segunda doseo que demonstra que a cobertura vacinal não é completa, logo, insuficiente para a erradicação da doença. Ainda, os autores evidenciaram que a queda na cobertura vacinal contra o sarampo está de alguma forma relacionada à localização geográfica e hesitação vacinal dessas áreas, influenciando negativamente a CV.…”