To thank you for taking part in my study, each time your name is quoted to me by email, you will automatically be entered into a prize draw to win a £20 voucher to Pizza Express.

However, you will have to answer 2 topical quiz questions before entering.

This means that the more you spread my disease, the more chance you have of winning! So wear the badge as often as you can to increase your chances.

The winner of the prize draw will be announced when the experiment finishes.