Which disease's major manifestations may consist only of fever, headache, muscle aches, and pains in the legs?

• A. Influenza
• B. Pneumonia
• C. Tuberculosis
• D. Malaria

Answer: (A)

Influenza often presents with a sudden onset of fever, headache, and prominent muscle aches, with fatigue and malaise that can be the dominant symptoms. The systemic inflammatory response to the influenza virus drives these fever and myalgia features, and in some cases respiratory symptoms (cough, sore throat) may be mild or even absent, so the major manifestations can be these constitutional symptoms alone.

Pneumonia typically adds cough, shortness of breath, and chest findings from lung involvement; tuberculosis tends to be a chronic disease with weight loss, night sweats, and a persistent cough; malaria classically features paroxysmal fever with chills and sweating and may show anemia and splenomegaly.