This is #2 in the Extreme Travel Series. The first book was Get Me Out of Africa. In the first book, Kes was accidentally initiated into the CIA way of life with her boss, James.
In this second book, Kes and James go on another CIA trip, but this time, to Haiti (written before the big earthquake of 2010). After being the only survivors of a plane crash, they run into a voodoo clan, Kes is eaten by leeches, and someone wants James and her dead.
In other words, it's just another 'fun' day for Kes while helping the CIA in a job she doesn't even have.