Pete,
I am not a doctor but a friend of mine is a scientist in charge of a lab where they design these vaccines. I am in the process of getting my Rabies shots for trip to Mongolia! It is a judgement call but this is the whole story; the difference between being vaccinated or not does indeed provide you with a theoretical extra 24 hours... BUT (big BUT) when you are vacinated (3 shots), you only need two more similar vaccine shots 1 day and 3 days after the bite and you are good to go. These additional vaccine shot are (or should) be normaly available in any city! If you plan to go to Brazil, FYI, Brazil is a rabies hotspot.

If you are NOT vacinated you will need a shot with 15ml SERUM (something entirely different) within 24 hours directly into the wound (extremely painfull) and that serum is very difficult to come by in remote area's. A giant country such e.g. Indonesia has none of it! Even here in the Netherlands it is only stocked in three places. Expect that none of it will be available in coutries like Peru and Equador! This means you will need an emergency Medivac to a country where they have the Serum and you will be tied down for minimum 3 weeks for after treatment.

On top of that note that Rabies is the ONLY virus with a 100% mortality rate! No Cure Possible. (Ebola with a mortality rate of some 50% and Marburg with 70% are benigh compared to Rabies)

Now ask your self again! :confused1:

Cheers,
Noel