Unlike meat and milk, bugs don't "contaminate" the soup. We don't eat bugs but the soup itself doesn't get spoiled if the bug is removed. Therefore, if one is sure the bug is completely removed, the soup can be eaten.
See detailed halachot of bugs in food here at dinonline
For instance, if a gnat falls into a pot of potatoes and gets lost
therein, the potatoes may not be eaten unless one ensures (by cleaning
off each potato) that the gnat is not present in the food he is
putting into his mouth. Similarly, if the gnat falls into a pot of
soup, the soup will need to be strained through a fine strainer, to
ensure that the gnat is not in the soup, before it may be eaten
(Shulchan Aruch, Yoreh De’ah 100:2).