At least swearing can't pass on TB and the like.
It is absolutely disgusting, and without starting the whole immigrant/foreigner debate off again - I have noticed a lot of foreigners doing it.
However, the worst instance had to be a young girl I saw doing it the other week (I hasten to add she was white).
Horrid. they should have their faces rubbed in it, I agree.
Whilst spitting is an anti-social and disagreeable habit, it is very unlikely that diseases are spread via this route.
Tuberculosis and other respiratory diseases are spread through breathing infected aerosolised droplets in the air, which are produced when an infected person coughs or sneezes.