Dr. Beck's field changes from caves, to bats, to "preventative medicine."
The second cave tour is several days after the first. Both tours contain the same tourists, wearing the same clothes.
A heavy rollbar-added for the rollover scene-is visible in the stolen ambulance.
There are palm fronds and leaved trees seen outside the hospital window when the doctor escapes, but during the car chase through the town you see the trees are all bare because its winter.