The symptoms of some travelers' diseases may be so mild and self-limited that they go unnoticed; many may be a miserable annoyance for a few days, and a few may cause an acute medical emergency. There are diseases that may not emerge until the traveler has returned home, with symptoms that may resolve, cycle, grow progressively worse, or linger. Left untreated, a few of the diseases can lead to blindness, organ failure, coma, and death.
The most frequently encountered symptoms of travelers' diseases are:
- Skin manifestations (e.g., rashes, sores, swelling)
Some diseases will cause:
- Hepatitis (liver inflammation) and its accompanying jaundice and headaches
- Meningitis and/or encephalitis
- Respiratory symptoms (coughing and/or difficulty breathing)
The World Health Organization (WHO) recommends that travelers have a medical exam upon their return if they experience symptoms in the weeks following their travel, or if they have a visited a country where malaria is present and returned with a fever. Those who have chronic diseases, such as cardiovascular disease or diabetes, or who may have been exposed to a serious infectious disease or spent an extended time traveling (more than 3 months) should also consult their doctor upon their return, even if they aren't having any symptoms.