The symptoms Peralta experienced were similar to those of the Chikungunya virus, which include joint pain, headaches and fever.
"I've had a fever and pain in my joints," said Peralta by telephone on Monday. "Feels like all my joints are sore. That's how I feel."
The virus is spread by mosquitos and has recently become more common in Caribbean countries. Peralta vaguely remembers encountering some during his off-days in the Dominican.
"I think so," Peralta said. "I kind of remember getting bit by a mosquito. One or two times."
Peralta said the only treatment has been Advil and Tylenol for his fever.
"It's supposed to last a week, then it just goes away," he said. "I do feel better today. Able to walk better."
Peralta, who is 2-3 with a 4.15 ERA in 43 appearances this season, expects the Rays to put him on the disabled list.
"I don't know yet, but it's most likely because I need a couple of days to get back," he said.
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.