This young squirrel came into our clinic at about 5 weeks old, about 1 week after arrival a small lump started forming. At first it appeared to be an abscess, soon afterward it was apparent that this lump was actually a botfly warble. Warbles are larvae from the Botfly. They use the animal only as a host; once they mature they will exit on their own. Generally they do not hurt their host unless the animal has 7 or more warbles.
If I found a squirrel in my yard with two warble lumps than I would leave them be, the warbles will exit in time. The only time I would intervene with a wild squirrel would be if it had so many warbles on it that the squirrel was becoming debilitated. Many times trying to trap, handle, and treat a wild animal can be more dangerous to the animal than letting it be. Fright alone can kill a wild animal.

Enjoy the video, gruesome as it can be, I do feel that it is very educational for learning how to easily remove these little bugs that use other animals as their host, especially in this case where the squirrel is already in a rehab situation