I've only used wet hops in the boil, never dry hopped, so I have no direct experience, but I've heard others have allegedly gotten infections from them, probably due to the increased water content making it easier to bacteria to get past the antiseptic properties. Counterposed to all the folks who've done it without out a problem, and I'd say there's a risk of contamination, but not a guarantee.
It's also (from what I understand) been established that those old beers traveling to India already had some Brett and/or wild yeast character.
Up Next: Pale Mild, Coniston Bluebird Bitter clone v1.0
Primary: ESB, Ordinary Bitter, Mild
Secondary: Sour Stout
Bottled: Düsseldorf Altbier, Sticke Altbier, Doppelsticke Altbier, Weizenbock, Berliner Weisse, Spruce Brown Ale, Arrogant Bastard Clone
Bottle "cellar": Brett B. Tripel, Imperial Red, Tripel, Quadrupel, Brett C. Oaked English Barleywine, Lamebic