Approximately 50% of people are willing to wait for over 21 months for an effective COVID-19 vaccine, according to findings of an online preference survey published in The Patient - Patient-Centered Outcomes Research.

A survey link was disseminated through social media posts in Twitter and LinkedIn in May 2020 to investigate the public's preferences with regard to willingness to wait over time periods ranging from less than 9 months to more than 21 months for a COVID-19 vaccine with 100% efficacy, compared with a 6-month wait for a vaccine with 50% efficacy. The survey included a brief sociodemographic questionnaire and a question on the participants' opinions on social distancing measures implemented by their governments.

Overall, 1069 adults in Europe (60%), North America (22.5%) or the rest of the world (17%) completed the survey; most were female (69%) and most were aged 18−44 years (68%).

Overall, 59% of participants were willing to wait at least 18 months for an effective vaccine and 51% were willing to wait for over 21 months. However, 10% participants were willing to wait for less than 9 months.

Men were willing to wait less time than women (odds ratio [OR] 0.59; 95% CI 0.46, 0.75), participants at higher risk of COVID-19 were willing to wait longer (OR 1.69; 95% CI 0.69, 2.27), and participants outside of Europe and North America were willing to wait less time than participants in Europe (adjusted OR 0.72; 95% CI 0.52, 0.99).

The most frequently endorsed government measures against COVID-19 were social distancing restrictions, hand hygiene and personal protective equipment, and restrictions on public mass gatherings.

"Despite the limitations of this study, our findings clearly suggest that governments and regulators should carefully consider the level of evidence required for vaccines to be granted marketing authorization, even if this prolongs clinical trial programs. Fast approvals of vaccines that result in suboptimal immunization of the general public may risk losing the public's trust in policy decisions," concluded the authors.