Quality and Safety of Vaccines Manufacturing: An Online Survey on Attitudes and Perceptions of Italian Internet Users.

Background: Vaccination is a worldwide public health practice that requires high uptake levels in order to effectively reduce the incidence of vaccine-preventable diseases. The manufacturing of vaccines is a complex process, and little is known about people's feelings and opinions on that. Our study aimed at investigating perceptions and attitudes of the general population towards the vaccine production process before the availability of COVID-19 vaccines. Methods: We designed a 15-question online survey in the Italian language which was spread via Facebook and an Italian website "Vaccinarsintoscana" between January and May 2020. We performed a descriptive analysis and applied statistical tests to assess differences in the given answers according to participants' sociodemographic characteristics. Results: The collected responses (135 participants) about the perceptions on vaccine production process were largely positive: not being concerned about the vaccine production (70.3%); believing the vials did not contain harmful substances (75.6%) and considering the precautionary withdrawal of some batches as highly effective (83.7%). In contrast, a less positive perception was found for the question about the conflict of interest between manufacturing companies and the control systems (48.9%). Moreover, people's perceptions towards the vaccine components (i.e., microorganism, adjuvants and opinion on batches withdrawal) also showed a good level of confidence and trust. Conclusions: Our study highlighted a generally positive attitude towards the vaccine production process and showed people's confidence in the control systems, safety and high standards of quality of the vaccine production process.