User blog comment:AYET/Let's Discuss Chapter 733/@comment-5511729-20131227123427

This was DEFINETELY Haoshoku Haki. Sabo stated clearly on mangastream page 21: "I'd heard of this happening before, but...". With this sentence he refers to the fight between Luffy and Don Chinjao because both of them used Haoshoku Haki in order to knock out all the other contestants. Even when Akagami no Shanks entered Whitebeard's ship not all of Newgate's crew members became have slobber at their mouths. The symptons that you're talking about were not shown at this meeting too.