Encouraging vaccination using the creativity and wisdom of crowds

Low vaccine uptake is a global public health challenge. Millions of dollars per year are spent on public health communication but evidence suggests its impact is far from optimal. Here we evaluate an approach for increasing the impact of public health communication to encourage vaccination that leverages the creativity and wisdom of laypeople to first generate and then select high-impact public health messages. We evaluate this approach in the context of attitudes towards COVID-19 and Human Papillomavirus vaccination, using a series of large online survey experiments conducted in Brazil, Mexico, and the US (total N=53,900), and a social media campaign field experiment (35M impressions) conducted in partnership with a public health NGO in Brazil. We find consistent evidence that the crowd-based approach can yield messages encouraging vaccination that are of higher impact than “standard-of-care” messages which public health campaigns may otherwise use in their public outreach.