Stephane Hess, Emily Lancsar, Petr Mariel, Jürgen Meyerhoff, Fangqing Song, Eline van den Broek-Altenburg, Olufunke A. Alaba, Gloria Amaris, Julián Arellana, Leonardo J. Basso, Jamie Benson, Luis Bravo-Moncayo, Olivier Chanel, Syngjoo Choi, Romain Crastes dit Sourd, Helena Bettella Cybis, Zack Dorner, Paolo Falco, Luis Garzón-Pérez, Kathryn Glass, Luis A. Guzman, Zhiran Huang, Elisabeth Huynh, Bongseop Kim, Abisai Konstantinus, Iyaloo Konstantinus, Ana Margarita Larranaga, Alberto Longo, Becky P.Y. Loo, Malte Oehlmann, Vikki O'Neill, Juan de Dios Ortúzar, María José Sanz, Olga L. Sarmiento, Hazvinei Tamuka Moyo, Steven Tucker, Yacan Wang, Yu Wang, Edward J.D. Webb, Junyi Zhang, Mark H.P. Zuidgeest, University of Leeds, Australian National University (ANU), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), Technical University of Berlin / Technische Universität Berlin (TU), University College of London [London] (UCL), University of Vermont [Burlington], University of Cape Town, Norwegian University of Science and Technology [Trondheim] (NTNU), Norwegian University of Science and Technology (NTNU), Universidad del Norte, Barranquilla, Universidad de Chile = University of Chile [Santiago] (UCHILE), Universidad de Las Américas [Ecuador] (UDLA), Universidad Técnica del Norte (UTN), Aix-Marseille Sciences Economiques (AMSE), École des hautes études en sciences sociales (EHESS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Seoul National University [Seoul] (SNU), Universidade Federal do Rio Grande do Sul [Porto Alegre] (UFRGS), University of Waikato [Hamilton], IT University of Copenhagen (ITU), Universidad de los Andes [Bogota] (UNIANDES), The University of Hong Kong (HKU), Ndatara surveys, Namibia Institute of Pathology, Queen's University [Belfast] (QUB), Technische Universität München = Technical University of Munich (TUM), Pontificia Universidad Católica de Chile (UC), Basque Centre for Climate Change (BC3), Ikerbasque - Basque Foundation for Science, Beijing Jiaotong University (BJTU), Hiroshima University, CN Chinese National Natural Science Foundation (72071017), the joint project of the National Natural Science Foundation of China and the Joint Programming Initiative Urban Europe (NSFC – JPI UE) (‘U-PASS’, 71961137005)., CL Instituto Sistemas Complejos de Ingeniería (ISCI), through grant ANID PIA/BASAL AFB180003., ES FEDER/Ministry of Science, Innovation and Universities through grant PID2020-113650RB-I00, Basque Government through grant IT1359-19 (UPV/EHU Econometrics Research Group), BERC 2018–2021 programme, MICINN María de Maeztu excellence accreditation (MDM-2017-0714)., KR Creative-Pioneering Researchers Program through Seoul National University., NA Ndatara Surveys., NZ Waikato Management School., ANR-17-EURE-0020,AMSE (EUR),Aix-Marseille School of Economics(2017), ANR-11-IDEX-0001,Amidex,INITIATIVE D'EXCELLENCE AIX MARSEILLE UNIVERSITE(2011), and European Project: 615596,EC:FP7:ERC,ERC-2013-CoG,DECISIONS(2014)
Despite unprecedented progress in developing COVID-19 vaccines, global vaccination levels needed to reach herd immunity remain a distant target, while new variants keep emerging. Obtaining near universal vaccine uptake relies on understanding and addressing vaccine resistance. Simple questions about vaccine acceptance however ignore that the vaccines being offered vary across countries and even population subgroups, and differ in terms of efficacy and side effects. By using advanced discrete choice models estimated on stated choice data collected in 18 countries/territories across six continents, we show a substantial influence of vaccine characteristics. Uptake increases if more efficacious vaccines (95% vs 60%) are offered (mean across study areas=3.9%, range of 0.6%-8.1%) or if vaccines offer at least 12 months of protection (mean across study areas=2.4%, range of 0.2%-5.8%), while an increase in severe side effects (from 0.001% to 0.01%) leads to reduced uptake (mean=-1.3%, range of -0.2% to -3.9%). Additionally, a large share of individuals (mean=55.2%, range of 28%-75.8%) would delay vaccination by 3 months to obtain a more efficacious (95% vs 60%) vaccine, where this increases further if the low efficacy vaccine has a higher risk (0.01% instead of 0.001%) of severe side effects (mean=65.9%, range of 41.4%-86.5%). Our work highlights that careful consideration of which vaccines to offer can be beneficial. In support of this, we provide an interactive tool to predict uptake in a country as a function of the vaccines being deployed, and also depending on the levels of infectiousness and severity of circulating variants of COVID-19. We acknowledge financial support as follows: CN Chinese National Natural Science Foundation (72071017), the joint project of the National Natural Science Foundation of China and the Joint Programming Initiative Urban Europe (NSFC – JPI UE) (‘U- PASS’, 71961137005). CL Instituto Sistemas Complejos de Ingeniería (ISCI), through grant ANID PIA/BASAL AFB180003. ES FEDER/Ministry of Science, Innovation and Universities through grant PID2020-113650RB-I00; Basque Government through grant IT1359-19 (UPV/EHU Econometrics Research Group); BERC 2018–2021 programme; MICINN María de Maeztu excellence accreditation (MDM- 2017-0714). FR FR French National Research Agency Grants ANR-17-EURE-0020 and the Excellence Initiative of Aix-Marseille University - A*MIDEX. KR Creative-Pioneering Researchers Program through Seoul Na- tional University. NA Ndatara Surveys. NZ Waikato Management School. UK European Research Council through the consolidator grant 615596-DECISIONS; internal funding through the Choice Modelling Centre (CMC). We would also like to express our thanks to technical support from Aix-Marseille University, and thank Sofia Hern ́andez Benavides (CL), Simon Dec Pedersen (DK) and Robbie Maris (NZ) for help in data preparation and analysis.