(S (S (NP (QP (NP (RB Between) (BASENP (NN three) (CC and) (NN six))) (NN million)) (NNS people)) (VP (VBP are) (VP (VBN thought) (S (VP (TO to) (VP (VB have) (VP (VBN been) (VP (VBN infected) (PP (IN in) (BASENP (NN 2005))))))))))) (PERIOD .))