A tool for early estimation of influenza vaccination coverage in Spanish general population and healthcare workers in the 2018-19 season: the Gripómetro

BACKGROUND: Electronic vaccine registries are not yet widely established. There is a need to real-time monitor influenza vaccine coverage, which may raise awareness to risk groups and professionals, and eventually allow to adopt tailored measures during the vaccination campaign. To evaluate the utility of the "Gripómetro", a demographic study designed to monitor national and regional influenza vaccine coverage on a weekly basis in Spain. Quantitative study based on surveys of the Spanish population between 18-80 years and a sample of primary care doctors and nurses randomly selected. Pre-proportional fixation has been established by Autonomous Communities and age group to guarantee the representativeness of all the autonomies. Interviews were conducted in 3400 households of general population and 807 respondents among health care professionals. We found that the results of influenza vaccination coverage in the population ≥ 65 years obtained by the Gripómetro for 2018-2019 season were mostly comparable with the official data presented by the Ministry of Health after the end of the vaccination campaign. The Gripómetro is a robust research method that provides real-time data and trends for influenza vaccine coverage along with other useful information related to vaccination such as intention to vaccinate, motivation and barriers to vaccination.