From the front line- a friend working on prevention.
....We know now that 50-75% of infected do not have symptoms so we were confused how anyone managed to track asymptomatic cases. (but this) virus changes the pH of your skin/eyes via intracellular Ca+ changes and infects the fine capillaries in the face regardless of fever, etc. It is very easy to identify the corona "blush": 3 rings: one sharp spot on each cheek and a pale ring of light skin around the mouth.
FLIR, military optics, etc can be used to do this long range.
We are working on a number of initiatives but...... (the vaccine programme) has not been fully government funded due to misspending, no western countries are investing in high throughput asymptomatic screening and the current plan seems to be just allow total infection so bio-security infrastructure is not required to carry on....