In a medical case that sounds strange and scary at the same time, an eight-year-old girl from Yangzhou in China’s Jiangsu province spent nearly a month vomiting live worms before doctors could identify the source of the bizarre condition.
The child began experiencing persistent bouts of vomiting—only what she expelled was not food or bile but small, wriggling worms around a centimetre long. Her father, increasingly alarmed, described each episode as producing “a handful” of these creatures. No one else in the family reported similar symptoms, adding to the family’s distress as local doctors failed to provide a diagnosis.
Hope came when the girl was taken to the Children’s Hospital of Soochow University. The paediatrician who examined her suspected that the problem might not be internal at all. She asked the family to collect a sample of the worms and take them to the local Centre for Disease Control and Prevention (CDC) for analysis.
That decision proved pivotal.
At the CDC, experts quickly identified the squirming specimen as larvae of the drain fly, or moth fly—a common pest in damp environments such as bathrooms and kitchen drains. These tiny insects are often dismissed as harmless nuisances, but in this case, they had found their way into the girl's digestive system, possibly through contaminated water.
According to South China Morning Post (SCMP), Xu Yuhui, a department head at the Yangzhou CDC, explained how easily the larvae might have entered her body. “If water from a toilet splash or while brushing teeth contains the larvae, they could be accidentally ingested,” he said.
While these larvae are not known to transmit diseases via the bloodstream, their presence in the gut can cause significant discomfort and complications, especially in children. Vomiting them out was the body’s instinctive way of rejecting the intruders.
The expert urged caution in handling drain flies, warning against crushing them with bare hands, as they may carry bacteria that can enter the body through the eyes or mouth. Instead, proper cleaning methods—such as flushing drains with boiling water mixed with salt and baking soda—are recommended to eliminate their breeding grounds.
For lasting protection, maintaining dry, clean bathroom and kitchen spaces is essential. What appeared to be just an annoying bug problem turned into a medical mystery, proving how even the smallest household pests can pose unexpected health risks.
