An (avian flu virus) can be deadly.Logical formLearned from17 sentences. A global (flu pandemic) may undergo an event.Logical formLearned from17 sentences. A vaccine can be for a (bird flu).Logical formLearned from17 sentences. A flu can be dangerous.Logical formLearned from17 sentences. (Bird flu) can be in persons.Logical formLearned from17 sentences. A (flu season) may arrive.Logical formLearned from17 sentences. A male may recover from flu.Logical formLearned from17 sentences. Some players may contract flu.Logical formLearned from17 sentences. Persons may die from flu.Logical formLearned from17 sentences. Signs may pertain-to a flu.Logical formLearned from17 sentences. A (winter flu vaccine) can be regular.Logical formLearned from17 sentences. Some persons may be suspected of having flu.Logical formLearned from17 sentences. A flu may be took from persons.Logical formLearned from17 sentences. A sign can be constituted-of-or-filled-with flu.Logical formLearned from17 sentences. A (bird flu strain) may mutate into a form.Logical formLearned from17 sentences.