Youngs and Hurrell were named in the starting XV, while Tonks appeared as a second-half replacement as England got the defence of their RBS 6 Nations title off to a winning start at an icy Sixways.
The one disappointment for the players was the game having to be played behind closed doors.
Worcester's staff had worked throughout the day to make the pitch playable but the surrounding area was beyond their control and concerns over the safety of the public getting to and from the ground led to a game originally scheduled for 8pm being played behind closed doors and starting at 5.30pm.
Tries came from centre pairing Henry Trinder and Luke Eves plus wing Seb Stegmann, with Rory Clegg adding a conversion.
England Under-20s: Charlie Sharples (Gloucester) (Rob Miller, Newcastle Falcons 58); Seb Stegmann (Harlequins), Henry Trinder (Gloucester), Luke Eves (Bristol) (Greig Tonks, Leicester Tigers 62), Will Hurrell (Leicester Tigers); Rory Clegg (Newcastle Falcons), Ben Youngs (Leicester Tigers) (Dan White, Leeds Carnegie 75); Ben Moon (Exeter Chiefs), Jamie George (Saracens) (James Clark, London Irish 67), Bob Baker (London Wasps) (Shaun Knight, Gloucester 54), James Gaskell (Sale Sharks) (Dan Williams, Gloucester 67), Graham Kitchener (Worcester Warriors), Courtney Lawes (Northampton Saints), Calum Clark (Leeds Carnegie, captain), Chris York (Harlequins) (Josh Ovens, Bath 62).
Italy U20: Alberto Benettin (Carrera Petrarca Padova); Giovanbattista Venditti (Almaviva UR Capitolina) (Luca Martinelli, GS Fiamme Oro Roma 59), Denis Majstorovic (Vibu Noceto) (Alberto Zorzi, Ruggers Tarvisium 70), Tommaso Benvenuti (Benetton Treviso), Michele Mortali (Plusvalore Gran Parma); Tommaso Iannone (Ruggers Tarvisium), Edoardo Gori (Consiag I Cavalieri Prato); Andrea Lovotti (Cammi Calvisano) (Edoardo Carugi, MPS Viadana 65), Andrea Manici (Plusvalore Gran Parma), Lorenzo Romano (Overmach Cariparma) (Carlo Fazzari, Cammi Calvisano 50), Lorenzo Contini (Plusvalore Gran Parma) (Stefano Scanferla, Cammi Calvisano 65), Joshua Furno (Antares Benevento), Filippo Ferrarini (Vibu Noceto) (Gabriele Cicchinelli, AlmavivA UR Capitolina 52), Emiliano Caffini (MPS Viadana), Luca Petillo (Mantovani Lazio, captain).
