LAUSR

Respiratory virus syndemics could burden the functioning of health care systems worldwide.1 How COVID-19 and influenza vaccine programs can promote each other is therefore highly important, especially if the COVID-19 vaccine becomes seasonal. Currently, there is a universal recommendation for flu vaccination in the United States,2 but not in China, Indonesia, and Malaysia, where it might be difficult or expensive to obtain a vaccine. It will be important to understand whether there are different decision-making processes that lead to the receipt of flu versus COVID-19 vaccines. Accordingly, using surveys from the United State, China, Malaysia, and Indonesia, this study characterizes the relationship between flu vaccine and COVID-19 vaccine uptake, and differentiates concerns about flu and COVID-19 vaccines, to better understand how adults make decisions about different vaccines.