2021, Year of the vaccine challenge: the role of behavioral science

Industry Insights


We believe that successful roll-out of the COVID-19 vaccination will have a bigger impact on most people’s lives than anything else in 2021.

Good uptake of the COVID-19 vaccine will be important for bringing the pandemic under control and allowing some normality to return. Based on what is known about the transmission rate of the virus and efficacy of COVID-19 vaccinations1,2, it is estimated that at least 60-70% of the population would need to be vaccinated in order to achieve herd immunity1.

Will people accept the vaccination?

The vaccine route to herd immunity will not be effective if people do not accept the offer of vaccination. Recent studies suggest that around a third of people in the UK and US are either uncertain or do not intend to accept an offer of COVID-19 vaccination3,4. Intention varies by country: in a study conducted across 19 countries, more than 80% of respondents in China, Brazil, and South Africa, and fewer than 60% of respondents in France, Poland and Russia said they would be likely to accept a COVID-19 vaccination.5

These are studies of intention to get vaccinated, not actual behavior. As we know from personal experience, intending to do something does not always lead to action – contextual, environmental, or habitual factors can get in the way.  Studies have consistently found intentions towards vaccination are higher than actual rates of vaccination. For example, only 57% of parents who intended to vaccinate their children against HPV did so.6

In addition, the COVID-19 vaccinations currently licensed or awaiting approval are given in two doses; 21 or 28 days apart. This presents another challenge to ensure adherence to the second shot, with likely decreases in efficacy if adherence is inadequate.  We also do not yet know how long immunity will last. People may be required to return for further COVID-19 vaccinations for years to come.

How can we increase the likelihood of acceptance and adherence?    

Multiple studies have shown that intention to get the COVID-19 vaccination is influenced by people’s attitudes towards it4,7,8. For example, a UK study of more than 32,000 people found that mistrust of vaccine benefits, worries about unforeseen effects, concerns about commercial profiteering, and a strong preference for natural immunity predicted unwillingness to get a COVID-19 vaccination7.

These types of beliefs, which may be based on misconceptions or be unduly negative, are potentially modifiable using a range of different communications informed by behavioral science and tailored to the needs of different groups. And those who intend to get the vaccine may benefit from interventions to increase their capability to do so (e.g. issuing reminders, using prompts and cues) and opportunity (e.g. providing local and easily accessible vaccination centers). These interventions can be further developed and refined as we learn more, both about the virus itself and people’s beliefs and behavior in relation to vaccination and other COVID-19 related measures.

A call to action

Healthcare professionals, public health officials and others, are used to tackling these challenges and must once again rise to the occasion, making sure that communication meets the needs of the community and in particular supports people who are currently uncertain or ambivalent about COVID-19 vaccination to make informed choices.


1.  Anderson RM, Vegvari C, Truscott J, Collyer BS. Challenges in creating herd immunity to SARS-CoV-2 infection by mass vaccination. Lancet. 2020;396(10263):1614-1616.

2.  Polack FP, Thomas SJ, Kitchin N, et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. N Engl J Med. 2020. DOI: 10.1056/NEJMoa2034577

3.  Pew Research Center. Intent to Get a COVID-19 Vaccine Rises to 60% as Confidence in Research and Development Process Increases. 2020. Available from: Click here. (accessed 18th December 2020)

4.  Sherman SM, Smith LE, Sim J, et al. COVID-19 vaccination intention in the UK: results from the COVID-19 vaccination acceptability study (CoVAccS), a nationally representative cross-sectional survey. Hum Vaccin Immunother. 2020:1-10.

5.  Lazarus JV, Ratzan SC, Palayew A, et al. A global survey of potential acceptance of a COVID-19 vaccine. Nat Med. 2020.

6.  Rickert VI, Auslander BA, Cox DS, Rosenthal SL, Rupp RE, Zimet GD. School-based HPV immunization of young adolescents: effects of two brief health interventions. Hum Vaccin Immunother. 2015;11(2):315-321.

7.  Paul E, Steptoe A, Fancourt, D. Anti-vaccine attitudes and risk factors for not agreeing to vaccination against COVID-19 amongst 32,361 UK adults: Implications for public health communications. 2020. Pre-print available from: Click here.

8.  Fisher KA, Bloomstone, B.A., Walder, J. Attitudes Toward a Potential SARS-CoV-2 Vaccine. Annals of Internal Medicine. 2020. Click here.