Crisis

A crisis is a situation which is difficult, unexpected, or an emergency. It is often an important "turning point", where a decision must be taken, affecting many people. Very often, this decision must be taken in relatively little time. The word is related to the Greek "κρίσις" (krisis). Examples include the sudden threat of war, or the occurrence of a natural disaster.
According to Steven Fink, a crisis manager, crises may: 
Crises occur in different fields. People may develop post-traumatic stress disorder, because they cannot deal with a crisis situation. Many countries and associations offer help lines, which can help people deal with a crisis situation.