OBJECTIVES: To quantify preferences for a combination vaccine for influenza and coronavirus 2019 (COVID-19) compared with an influenza mono-vaccine among consumers in the United Kingdom (UK).
METHODS: Preference was assessed using a threshold technique series included in a broader stated-preference survey. In the initial threshold technique question, the combination and mono-vaccine had identical flu vaccine efficacy and side effect risks, while the combination also offered protection against COVID-19. Subsequently, the risk of moderate to severe systemic, flu-like symptoms (FLS) due to the vaccine was systematically varied (range, 0%-30%) to estimate respondents’ tolerance for FLS risk in exchange for the additional protection and convenience of the combination vaccine compared with the mono-vaccine. Choices were analyzed using descriptive statistics and interval regression.
RESULTS: Threshold technique data were collected from 600 UK consumers (200 aged 18-49 years, 200 aged 50-64 years, and 200 ≥ 65 years). Half of (298 [49.7%]) respondents had at least one non-age risk factor for severe influenza complications (as defined by the National Health Service). Most (448 [74.7%]) respondents preferred the combination vaccine to the mono-vaccine. On average, UK consumers were willing to accept a maximum FLS risk of 24.1% (95% confidence interval, 23.0-25.2) in exchange for a combination vaccine rather than a mono-vaccine. A minority of respondents (45 [7.5%]) would not accept any risk of FLS for a combination vaccine. Higher education and previous experience with flu and COVID-19 vaccination increase risk tolerance, while consumers with risk factors for serious flu complications are less risk tolerant.
CONCLUSIONS: The majority of UK consumers would likely prefer the added protection and convenience of a single shot combination influenza and COVID-19 vaccine compared with a flu mono-vaccine. Consumers would be willing to accept increased risks of FLS in exchange for the added protection and convenience of the combination vaccine.