Aerosol pandemics/Critical jobs

In a severe enough aerosol pandemic, societies would want to reduce contagion while keeping critical supplies and services. Exaggerating to make a point, if everyone stays in their own personal cupboard, no-one dies from flu but we all die from something else. So, which jobs are critical? Can some activities be redesigned? And how can societies think practically to minimise contagion while keeping whatever is vital?

Official lists may not be very helpful, as they lack a mechanism to determine priorities. Example from the UK: https://www.gov.uk/guidance/essential-workers-prioritised-for-covid-19-testing