disease has primary infectious agent disease has feature disease has infectious agent Muscle weakness Headache infectious disease influenza https://www.malacards.org/card/influenza influenza infection ICD9:487 Influenza with other manifestations flu icd11.foundation:145723401 ICD9:487.8 orthomyxoviridae disease or disorder An acute viral infection of the respiratory tract, occurring in isolated cases, in epidemics, or in pandemics; it is caused by serologically different strains of viruses (influenzaviruses) designated A, B, and C, has a 3-day incubation period, and usually lasts for 3 to 10 days. It is marked by inflammation of the nasal mucosa, pharynx, and conjunctiva; headache; myalgia; often fever, chills, and prostration; and occasionally involvement of the myocardium or central nervous system. MESH:D009976 UMLS:C0021400 orthomyxoviridae infectious disease DOID:8469 MONDO:0005812 MEDGEN:9466 orthomyxoviridae caused disease or disorder EFO:0007328 SCTID:61700007 MESH:D007251 NCIT:C53482 viral respiratory tract infection primary viral infectious disease Orthomyxoviridae