An English adventurer named Will Millard went to the jungles of New Guinea to study the Korowai people who still live in tree houses and use stone tools. It ended up as a two-part series on the BBC called "My Year With the Tribe".
In one clip a tribesman inserts a grub into Will's ear to clear out the waxy buildup. And it works. He can actually hear it eating the wax. It eventually comes out on its own.
You can see visible male genitalia at 0:47.
The grub comes crawling out at 1:32