Birds may be infected with a strain.Logical formLearned from2 sentences. Swans may be infected with h5n1.Logical formLearned from2 sentences. A pair may be infected with a virus.Logical formLearned from2 sentences. Humans may be infected by a strain.Logical formLearned from2 sentences. (Flu viruses) may infect persons.Logical formLearned from2 sentences. Tens of thousands of persons may be infected through an industry.Logical formLearned from2 sentences. Some members of a family may be infected by a virus.Logical formLearned from2 sentences. A duck may be infected with (bird flu).Logical formLearned from2 sentences. (Bird flu) may infect a duck.Logical formLearned from2 sentences. Some birds may be infected with a (bird flu strain).Logical formLearned from2 sentences. Birds may be infected with a (bird flu strain).Logical formLearned from2 sentences. Chickens may be infected with a type of (bird flu).Logical formLearned from2 sentences. (Backyard chickens) may be infected with (bird flu).Logical formLearned from2 sentences. Swans may be infected with a (h5n1 bird flu strain).Logical formLearned from2 sentences. A parrot may be infected by birds.Logical formLearned from2 sentences.