ivermectin is typically used for tapeworm infection.
as the public starts using ivermectin more widely, it's inevitable that some people will discover they have had tapeworm for years.
In Southeast Asia, many countries have an annual 'national deworming day' where everyone is encouraged to take a dose of mebendazole.
In those same countries, you don't often see many fat people either… I think they might be on to something.