( This ( ( would ( have ( ( an ( immediate impact ) ) ( of ( inhibiting ( ( the spread ) ( of ( viruses ( like Melissa ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This)) (VP (MD would) (VP (VB have) (NP (NP (DT an) (JJ immediate) (NN impact)) (PP (IN of) (S (VP (VBG inhibiting) (NP (NP (DT the) (NN spread)) (PP (IN of) (NP (NP (NNS viruses)) (PP (IN like) (NP (NNP Melissa)))))))))))) (. .)))
This would have an immediate impact of inhibiting the spread of viruses like Melissa.
(ROOT (S (NP (NNP Tamiflu)) (VP (VBZ inhibits) (NP (NP (NN spread)) (PP (IN of) (NP (NN virus))))) (. .)))