Answer: Dermatobia hominis, the human botfly (3rd instar).
In this case, we see Dr. Chaccour applying an occlusive paste to 'suffocate' the botfly and facilitate its removal. Any type of thick paste will work - even bacon fat. Although we can't see the respiratory spicules, this fly larvae can be identified by the following features:
1. Robust (broad) body, often tapered at the terminal end (especially in earlier instars).
2. Concentric rows of spines on all but the terminal 3 body segments.
3. Found in Central and South America and the Caribbean
4. Causes furuncular myiasis (non-migratory boils)
Jon pointed out an excellent web page on this insect by the University of Florida. I'd encourage you to check it out - it has some beautiful images of the different instar stages.