A country may have cases of (bird flu).Logical formLearned from14 sentences. Avian flu may be detected.Logical formLearned from14 sentences. (Bird flu) can be after some human deaths.Logical formLearned from14 sentences. A war can be on (bird flu).Logical formLearned from14 sentences. Surveillance can be for (bird flu).Logical formLearned from14 sentences. A strain of (bird flu) may kill millions.Logical formLearned from14 sentences. A (flu virus) may undergo a mutation.Logical formLearned from14 sentences. An extent may pertain-to a (bird flu outbreak).Logical formLearned from14 sentences. Transmission of (bird flu) can be an explanation.Logical formLearned from14 sentences. A (bird flu outbreak) can be regional.Logical formLearned from14 sentences. A country may have cases of (bird flu).Logical formLearned from14 sentences. A country may report a (flu outbreak).Logical formLearned from13 sentences. A (flu virus) may be identified.Logical formLearned from13 sentences. A country may report some deaths of a flu.Logical formLearned from13 sentences. (Flu vaccines) may undergo a development.Logical formLearned from13 sentences.