I see no need for this government health censor to be sub-dermal. Perhaps shape it as a cameo brooch for formal female wear, or as an addition to the Apple watch?
I mean if sensoring the population is the goal. Just go full police state like they did to my friend on his second DUI the state put an ankle bracelet on him that had sensors to detect alcohol on the skin that was 8 years ago the sensor package is now small enough to fit on a dermal patch like the birth control patches that are 3 cm x 3 cm. Same tech could sense any number of blood parameters, alcohol,drugs, vivid, HIV, Ebola, TB, sodium, glucose the list is long and scary. The 4th should protect from this kinda abuse but ask any DUI offender it don’t mean diddly unless you want to never drive again or work so yeah about that 4th.