Fever of unknown origin - could it be related to travel?

Could be: Fever of unkown origin is usually defined as fever (>100.5f)for longer than 6 weeks duration without a diagnosis after through investigation.

Of course: Depends upon where you have traveled and what you were exposed to. Less than 50% of true fuo's are due to infection. When they are due to infection, the most common disease likely to have been gotten by travel would be tuberculosis. Go see an infectious disease doctor. Modestly speaking, they are all good.