Question

When should I take precautions with regard to health, safety, and the like?

Answer:

Don't be paranoid! (Rosh Yeshiva Rebbi Yisrael Falk shlit"a). Hashem wants you to be "normal," just like everybody else. If something is not so common, don't worry about it at all. But more than anything, like Shlomo haMelech says (Mishlei 18:14), and the Vilna Gaon explains: A happy person is a healthy person, whereas a depressed person will not be helped by all the "health precautions" in the world!