So there are so many diseases. Therefore eating is so important thing. And the germs, they come out from the mouth very easily. Very easily. Formerly there was politics. They were called viṣa-kanyā, "poison girl." The politicians used to keep. I do not know whether nowadays the politicians keep. But we find from Vedic literature, viṣa-kanyā. Viṣa-kanyā means a girl, from the childhood, is injected poison, little by little, little, little, little, little. So when she is grown up, she, whole body is poisonous. So the politician used to engage such girl to kill his opponent politician. Very nice, beautiful girl, and (s)he will go, and as soon as the kissing will be there, he will die. Just like poisonous. Yes, it is fact. It is not story. I read in medical journal. There was one... Not medical journal. In logic class. It is called some "Typhoid Mary." "Typhoid Mary." A girl whose name was Mary, wherever she would go, all the people associating with her will be attacked with typhoid. Then the medical board examined her blood, that she is full of typhoid germs. So therefore wherever she goes, people become infected. These are medical facts.
So therefore association is so important. Saṅgāt sañjāyate kāmaḥ. According to association we infect different qualities. That they do not know. But nature's law is so particular, as soon as you infect by association a particular type of quality, you have to suffer for that. Therefore Caitanya Mahāprabhu, He was asked by one devotee, gṛhastha devotee, householder, "Sir, what is the duty of a gṛhastha devotee, Vaiṣṇava?" Devotee means Vaiṣṇava. So He immediately informed him, asat-saṅga-tyāga ei vaiṣṇava-ācāra: (CC Madhya 22.87) "A Vaiṣṇava's behavior should be that he should give up the company of asat, nondevotee." That is his first business. He should give up the company of nondevotee. This is first business. Because he will be infected. Therefore we insist our students that "Don't go out." Even you are discomfortable, you should tolerate, but you should not go out of the society. Then you will surely fall down, surely fall down.