Influenza, virus not identified

**Definition:** Any disease of the respiratory system, caused by an unidentified strain of influenza virus. These diseases are characterised by fever, cough, headache, myalgia, arthralgia, or malaise. Transmission is by inhalation of infected respiratory secretions.

**Inclusions:** - Influenza specific virus not stated to have been identified - Viral influenza specific virus not stated to have been identified

**Exclusions:** - Haemophilus influenzae [H. influenzae] meningitis - Haemophilus influenzae [H. influenzae] pneumonia