The 29-year-old woman had no idea why her eye was swollen shut. She was in unbearable pain. But when the woman, identified by her surname He, received treatment in Taiwan, doctors didn’t find a bacterial infection. While looking at He’s eyes through a microscope, Dr. Hung Chi-ting, the head of ophthalmology, witnessed something he hadn’t seen before. Insect legs were wiggling from one of her eye sockets. Hung yanked out a small bee, known as Halictidae or a “sweat bee.” And it was alive. Soon he extracted a second. And a third. And, finally, a fourth. Craving salt, the bees had been feeding off He’s tears, said Hung, who described it as a “world first.” “The woman will be fine. The bees will be fine,” said Matan Shelomi, an associate professor of entomology at National Taiwan University. “I don’t expect we’ll ever see it again.”