(S (S (PP (IN As) (PP (IN of) (BASENP (NN now)))) (COMMA ,) (S (BASENP (DT the) (NNP H5N1) (NN virus) (NN strain)) (VP (VP (VP (VBZ does) (RB not)) (VP (VP (VB pass) (ADVP (RB easily))) (PP (TO to) (BASENP (NNS humans))))) (CC and) (VP (VP (VBZ does) (RB not)) (VP (VP (VB spread) (ADVP (IN at) (DT all))) (PP (IN between) (BASENP (NNS humans)))))))) (PERIOD .))