Tests may detect a virus.Logical formLearned from18 sentences. Victims may pertain-to a virus.Logical formLearned from18 sentences. Some questions can be about a virus.Logical formLearned from18 sentences. Positive tests can be for virus.Logical formLearned from18 sentences. An attack may pertain-to a virus.Logical formLearned from18 sentences. A virus can be elusive.Logical formLearned from18 sentences. A virus may attack an immune system.Logical formLearned from18 sentences. A virus may undergo complications.Logical formLearned from18 sentences. Contact can be with a virus.Logical formLearned from18 sentences. Patients may have a virus.Logical formLearned from18 sentences. An infection can be with a virus.Logical formLearned from18 sentences. A mystery can be about a virus.Logical formLearned from18 sentences. A virus may spread against (ocean currents).Logical formLearned from18 sentences. A new type of virus can be a culprit.Logical formLearned from18 sentences. (Bone-marrow cells) may resist a virus.Logical formLearned from18 sentences.