A spread may pertain-to a (respiratory virus).Logical formLearned from15 sentences. Protection can be against a virus.Logical formLearned from15 sentences. Foot-and-mouth can be a virus.Logical formLearned from15 sentences. A carriers may pertain-to a virus.Logical formLearned from15 sentences. Viruses may be knowned to man.Logical formLearned from15 sentences. A virus may cause cancer.Logical formLearned from14 sentences. A virus can be serious.Logical formLearned from14 sentences. Virus may undergo an infection.Logical formLearned from14 sentences. A (flu virus) may cause some infections.Logical formLearned from14 sentences. A virus may take root.Logical formLearned from14 sentences. A country can be free of a virus.Logical formLearned from14 sentences. (Child transmission) may pertain-to a virus.Logical formLearned from14 sentences. Birds can be with a virus.Logical formLearned from14 sentences. A virus may cause polio.Logical formLearned from14 sentences. A virus can be destructive.Logical formLearned from14 sentences.