(S (S (SBAR (WHADVP (WRB How) (RB precisely)) (S (BASENP (DT the) (NN infection)) (VP (VBD was) (VP (VP (VBN transported) (PP (IN from) (BASENP (DT the) (NN ranch)))) (PP (TO to) (BASENP (DT the) (NN spinach) (NN field))))))) (VP (VBZ is) (VP (ADVP (RB still)) (VBN unknown)))) (PERIOD .))