The floating tip of the iceberg represents what the physician sees in the community as:

Health professionals see only a small part of the illness in the community, just as only a small part of an iceberg is visible above the surface of the water. This is what is called " the tip of the iceberg", as information on the submerged portion is not available.  But the inapparent cases are important for their role in transmission. Since many inapparent infections can be transmitted and can produce disease in others, it is not sufficient to direct disease management procedures solely to clinically apparent cases.