Romain Crastes dit Sourd & colleagues – The path towards herd immunity: Predicting COVID-19 vaccination uptake through results from a stated choice study across six continents

Our paper on predicting COVID-19 vaccination uptake in 18 different countries and territories using stated choice surveys and latent class models has been accepted for publication in Social Science & Medicine (ABS4).

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.

Link to the paper: https://doi.org/10.1016/j.socscimed.2022.114800

Authors: 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 PY Loo, Hazvinei Tamuka Moyo, Malte Oehlmann, Vikki O'Neill, Juan de Dios Ortúzar, María José Sanz Sánchez, Olga L Sarmiento, Steven Tucker, Yacan Wang, Yu Wang, Edward Webb, Junyi Zhang, Mark Zuidgeest.