When is flu not flu?

An otherwise fit and healthy physiotherapy student presents with symptoms that seem like pneumonia

Sara is a 21-year-old physiotherapy student who presents with a 10-day history of dry cough, lethargy, headache and fever.

She initially saw her GP one week ago who diagnosed her with influenza and treated her with paracetamol and ibuprofen.

However, her symptoms worsened, she was seen by another GP and sent to the ED.

Sara is a non-smoker, denies exposure to birds and does not recall exposure to patients with tuberculosis while attending her clinical placement.

Her past medical history is unremarkable and she does not take any medications.

On physical