You statutory health insurance is also valid abroad. The condition is that a so-called social insurance agreement exists with that country (An agreement of this kind exists with most European countries).
Under tk.de: Travel you will find detailed information on what you need to know before your departure abroad: Does my statutory health insurance cover my country of destination? What must I do in case of illness? What if transport back to Germany is necessary? www.tk.de will give you answers to these and many other questions.