A version of the street calculus for #covid19 might include face masks, hazmat suits, hand gel as well as physical signs 1/ 
Paul Slovic uses this cartoon in their paper on risk perception and the heuristics (mental shortcuts) we use to take decisions under uncertainty. You can read it here 2/ onlinelibrary.wiley.com/doi/full/10.11…
These mental shortcuts reflect the biases we have. Sometimes they work well. They are what behavioural insights aka nudge theory is based on 3/ bi.team
These biases in include things like loss aversion - we don’t like losing things we already have. This heuristic was used in messaging for another recent important event 4/ link.springer.com/article/10.100…
Other biases include: we do things that make us feel good about ourselves and others, or we do things that we see others doing (social norms). These are the kinds of behavioural insights are shaping messages around #covid19 at the moment - a national effort, helping others etc.
Nudge does not represent all of public health behavioural science. But neither do the founders of nudge think its always important 6/
Behavioural insights will therefore face two challenges. For governments, as cases continue to rise, it will be difficult to see how/whether these interventions are working. The emphasis placed on them will likely depend on trust between those experts working together 7/
For the public, continuing to follow advice could depend on their emotional reaction to #COVID19, and their perception of whether interventions are actually working or not. As cases rise, as predicted, and time goes on, money and food become increasingly important 8/
At that point, our understandings of disease (our own lay epidemiology) start to erode and override official advice. This is why it’s important for that advice to be sensible from the outset and take into account the way we will interpret it 9/
For example, the current guidance on self-isolation says don’t go out for a walk. Without strict enforcement (police/army on the streets) that conflicts with evidence on transmission (warm indoor environments with close contact) and the psychological challenge of isolation 10/
These lay epidemiologies will become increasingly important - and advice which doesn’t take them into account will be counterproductive /ends
