should we not be allowed to know if they are walking around with HIV virus, or Hepatitis virus, or any other transmissible virus.

Privacy no longer matters. That passport will soon include more than medical information on it too and perhaps through some smart gadget, it will read the last time you were angry, if you swore and whether or not you separated your rubbish for recycling.

There are a lot of viruses that are transmissible by air, and or exchange of bodily fluids like sweat, spittle and blood.

Yes. But no one seems to be restricting movements on these. Just imagine the uproar if obese people were locked down because of their risk of normalizing obesity in the general population.