8-year-old Chinese girl vomits live worms for a month as doctors trace cause to household drains

An 8-year-old girl in China vomited worms for a month before doctors found drain fly larvae from household water were the cause.

In a disturbing incident, an eight-year-old girl from Yangzhou City in eastern China’s Jiangsu province spent nearly a month vomiting live worms, leaving both doctors and her family baffled — until the unusual culprit was finally identified, according to a report by the South China Morning Post (SCMP).

Doctors discovered a Chinese girl’s mysterious vomiting was due to larvae from drain flies, commonly found in damp home areas like toilets and kitchens. (Representational image/Unsplash)

Mystery illness stuns doctors and family

The unidentified girl had been repeatedly vomiting what her father described as “a handful of 1cm-long worms” each time, despite no one else in the family experiencing similar symptoms. Numerous visits to local doctors failed to explain her condition, leaving the family increasingly desperate for answers.

It wasn’t until the child was examined at the Children’s Hospital of Soochow University in Jiangsu that paediatrician Dr Zhang Bingbing made a breakthrough. She advised the family to take a sample of the worm to the local Centre for Disease Control and Prevention (CDC) for further analysis.

Rare diagnosis: Drain fly larvae

There, staff quickly recognised the specimen — it was the larva of a drain fly, also known as a moth fly. These insects are frequently found in damp, dark places such as household drains, bathrooms, and kitchens, particularly in southern regions of China during the humid summer months.

The girl's family later recalled noticing the presence of such small, fuzzy insects in their home, but never imagined they could pose a health risk.

How the worms entered the girl’s body

According to Xu Yuhui, a department chief at the Yangzhou CDC, the worms likely entered the girl's body through contact with contaminated water. “When the child brushes her teeth or flushes the toilet, the worms might enter her system through splashes of water,” he said.

While the larvae are not known to spread disease through blood, their presence in the human digestive tract can still cause serious distress.

Warnings and prevention measures

According to a report by SCMP, experts have cautioned against squashing drain flies with bare hands, as the bacteria they carry can be transferred to humans through contact with the eyes or mouth. Instead, they recommend eliminating the larvae by pouring boiling water mixed with salt and baking soda down the affected drains.

For long-term prevention, maintaining clean, dry kitchen and bathroom environments is key to ensuring these flies do not breed or spread.