Anxiety indicators were assessed through two closed-format questions assessing personal worries about catching the virus (measured on a 4-point scale, from very concerned to not at all concerned), as well as questions assessing friends and families' estimates of the risk (4 point scale, from very high to very low). We used closed format questions for two questions assessing the purchase, or intention to purchase, specific items, such as face masks ("Have you already bought (or are you intending to buy) anything in preparation for a swine flu epidemic (e.g. face masks, food, tissues, cleaning materials)?" (yes/no responses). We accompanied this with an open-ended question for those who indicated they had/intended to purchase an item ("what have you bought?") with responses categorised for frequency in Malaysia and Europe, with the most common categories reported below. We also assessed whether respondents expected to modify their public transport use as a result of the threat (3 point scale: increase transport use, decrease transport use, or remain the same, collapsed into the categories 'less' and 'much more or the same' for analysis), and whether respondents intended to cancel or delay travel plans (yes / no). An open-ended question asked 'how can you protect yourself from infection?' with the most frequent responses coded into categories by our research team in Malaysia and Europe.