All right fine, you guys win, okay? When I said that, I meant that for my personal experience, TD is something I can get over in a day or 2, a more serious "bacterial infection" is something that makes me violently ill, requiring treatment by a dr and several rounds of antibiotics and generally lasts for a few weeks. In that event, the Cipro I originally inquired about is an emergency med to get me through until I can see a dr, either at home or in Coz. Better? Sheesh!
Nope, still not right.
If you have a bad ETEC infection, the antibiotics should do the job completely in 3-5 days; a single 500mg Cipro and you'll already start feeling some relief as the bugs are killed off, the full course is the "scorched earth" policy necessary so none survive to regroup (and with greater resistance).
CDC says (same cite as before): "Travelers who develop three or more loose stools in an 8-hour period---especially if associated with nausea, vomiting, abdominal cramps, fever, or blood in stools---may benefit from antimicrobial therapy. Antibiotics usually are given for 3-5 days."
If you've got something that lasts for a few weeks, requiring 'several rounds' of antibiotics, and you're violently ill, I strongly, strongly suggest you don't self-medicate, but see a doctor. No need to take the Cipro 'until you can see a doctor', go see a doctor right away.
Three or more loose stools is one thing, but if you've got blood in them stools and vomiting, you might have something far worse than ETEC. If the Cipro self-medication doesn't work, you might find yourself hooked up to an IV in a Mexican emergency room and that doesn't sound like any fun.
That's why I think the "emergency Cipro" is only a good idea if you're somewhere without doctors and hospitals, like a liveboard, or where the doctors and hospitals might be worse than the cure, such as PNG or Truk. On Cozumel, medicine is modern enough and you'll be fine with a locally-recommended doc.
