@Miller,
President Obama paid the price of having bad breath by eating burgers like crazy while doing his first campaign throughout the States when he run for president.
He might suffered of reflux then. Too much junk food at his age, plus the stress might have caused him that temporary condition. A condition that might become permanent later on.
With this in record, the current sore throat must require an examination other than the doctor looking at his throat.
The cause was reflux. This is a concern, the stomach acids might cause other than sore throat and can trigger other conditions as cancer.
I do not like president Obama at all, but I'll hope he receives the proper care to avoid more damage to his esophagus and throat.