But he is still thinking of his profession in some twisted, incredible sense. Even now, in his state, he means to try to help them (in his own definition of 'help') with their "infection."
It's that he seems to be thinking within the limits of his own definitions that make me skeptical as to whether or not he'd listen.

Do no harm, physician!

Pull a Captain Kirk by pointing out that Fil's rather freaky-looking arm is obviously unclean, and that therefore, he must remove it.