The botfly is linked in dream books to something that has got under the skin — a worry or influence that grows unseen and is unpleasant to face.
When this appeared in your dream, what were you feeling?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.