I found the reason hygiene control is difficult here in Hong Kong, finally. People living here don't wash hands after toilet! Alas, Jesus Christ! Confucius should have taught them to wash hands after doing so. I could not figure out why I have diarrhea after working in the university until I red a news article that says people in China don't have a custom to wash hands before eating. This is the hint. Hmmm ... TV spot commercials urge them to wash hands or cover the mouths in cough, have masks in cold. I have never watched these fundamental instructions in TV programs in civilized countries. It's nice for me to learn the essential difference between China and other countries by long stay in Hong Kong. In Mainland, it should be much worse.
By the way, I found another article that says the British don't wash hands after toilets. Haven't they strengthened this bad feature of China? This is an enigma of hygiene level in Hong Kong, India, Egypt, and others once under the Union Jack.