A method, system, and computer product for detecting an oral temperature for a human include capturing a thermal image for a human using a camera, detecting a face region of the human from the thermal image, detecting a mouth region on the face region, comparing a temperature value on the mouth region to a reference temperature value on a first other face region, detecting an open mouth region on the mouth region based on a comparison result of the temperature value on the mouth region to the reference temperature value of the first other face region, determining whether a mouth of the human is open enough for an oral temperature to be detected, and computing the oral temperature based on temperature values on the mouth region and at least one other face region, responsive to the determination of the mouth being open enough for the oral temperature to be detected.