What Causes High BP, Chronic Swelling In Feet, Flushing Face, Chest And Weakness?

My 31 year old son, who spent about a year in Brazil 10 years ago, has been having serious problems with high blood pressure, chronic swelling of feet and ankles, fast heart beat, sensitivity to heat, flushing face and chest, weakness. He recently had a seven day bout of fever, vomiting, and diarrhea. His fever eventually broke, and most of the symptoms above that he s experienced for the past three years appear to be gone. Could he have contracted some rare disease in Brazil or from mosquitoes, etc. in Florida?