According to the story:
"If a child has a really high fever, or is in significant discomfort, or won't eat or drink anything for days, that's a red flag for concern," said Dr. Paul Casamassimo, director of the American Academy of Pediatric Dentistry's Pediatric Oral Health and Research and Policy Center. The analysis didn't completely dismiss a parent's intuition. It found the most common symptoms of teething were swollen gums, drooling and crankiness. Symptoms shouldn't last for more than three to five days, Casamassimo said, but he did acknowledge that it can feel much longer. "By and large, symptoms are not a chronic thing. They come and go, and the job of the parent is to comfort the child, and keep their finger on the pulse of their child. Is the child eating? Staying hydrated?" Casamassimo said.
SOURCE: American Academy of Pediatric Dentistry