Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Stress Movement speed from the start Warwick is an excellent jungler and can dominate lanes too. The key is in lifesteel items and being able to catch enemies and kill them before they reach turrets. Get a Black Cleaver after your first Bloodthirster. The cleaver syncs very well with Infinite Duress. Then just make more Bloodthirsters till the game is over. Their passives stack granting an additional 120 attack and 30% lifesteel. With this it is easy to run in and take on multiple champions and towers at the same time.