Public preferences and decision-making for mpox vaccination in the African region: a multinational discrete choice...

After the WHO prequalified the first vaccine against mpox, we aimed to identify the influence of vaccine attributes on mpox vaccination preferences among the African adults.

A discrete choice experiment was conducted among 1832 African adults across six countries. Respondents answered eight questions, each requiring them to choose between two hypothetical vaccines, with variations in distance from home to vaccination facilities, cost, effectiveness, duration of the protective effect, supply and side effects. A mixed logit model was employed to estimate vaccination preferences. Willingness to pay and changes in probability were also estimated from the regression coefficients.

The strongest vaccine attribute was the higher effectiveness of vaccines (≥90% vs <60%: b=1.196, 95% CI 1.089 to 1.303), then followed by a longer duration of protective effect (lifetime vs <6 months: b=1.053, 95% CI 0.920 to 1.186), a low risk of side effects (<30% vs ≥30%: b=0.495, 95% CI 0.427 to 0.562) and sufficient vaccine supply (sufficient vs limited: b=0.417, 95% CI 0.360 to 0.475). Although compared with a walking distance of 60 min, a walking distance of 45 min was significant (b=0.402, 95% CI 0.296 to 0.508), there was no significant difference for walking distance at 15 and 30 min. Scenario prediction analysis showed that higher vaccine effectiveness (≥90%: 53.55%; 80%-89.99%: 51.41%; 60%-79.99%: 25.85%), a longer duration of protective effect (lifetime: 48.28%; 12-36 months: 25.51%; 6-11 months: 14.39%), lower vaccine costs (US$0: 28.10%; US$20: 25.42%; US$100: 14.34%), a risk of side effects of less than 30% (24.24%) and sufficient vaccine supply (20.57%) all increased the probability of vaccine uptake. Populations living with children preferred vaccines with sufficient supply and lower cost, compared with those living without children.

In Africa, alongside providing more reliable mpox vaccines, offering sufficient vaccine free of charge, particularly to those living with children, would encourage higher vaccine uptake.