( ( Both parasites ) ( ( can ( originate ( from ( ( ( human and ) animal ) wastes ) ) ) ) . ) )
(ROOT (S (NP (DT Both) (NNS parasites)) (VP (MD can) (VP (VB originate) (PP (IN from) (NP (UCP (NN human) (CC and) (NN animal)) (NNS wastes))))) (. .)))
Both parasites can originate from human and animal wastes.
(ROOT (S (NP (NNS Nematodes)) (VP (MD can) (VP (VB be) (NP (NP (DT a) (NN parasite)) (PP (IN of) (NP (DT both)))))) (. .)))
Nematodes can be a parasite of both.