what causes a low grade fever and a headache for weeks at a time?
A headache and fever may be a sign of an infection that is localized to your brain and/or spinal cord, which forms your central nervous system. Examples include: meningitis, encephalitis, or a brain abscess. Systemic or whole body infections, such as the flu or early HIV symptoms, may also cause a headache and fever. This all being said, sometimes a headache and fever is a sign of a viral infection that needs to run its course. It can be hard to distinguish, though, so be sure to get it checked out.