Tapeworm
At 6.2m long the tapeworm was three-and-a-half times the length of the average giraffe's neckEraxion/iStock

A 38-year-old Chinese man discovered a 6.2m-long tapeworm growing inside his stomach, after complaining to doctors of a severe stomach ache. The man had a diet rich in raw beef, and said he had been losing weight at an alarming rate.

The doctors in Shiyan, China found a tapeworm's egg in the man's faeces, which prompted them to prescribe him drugs until the huge worm fell out. It was only then that the doctors could confirm that the man had become infected by the taenia saginata – a worm that is transferred in raw beef.

Giant tapeworm
The tapeworm was measured at 6.m-longLi and Guo, The New England Journal of Medicine

"During the previous two years, he had been seen by several different doctors and had been given clinical treatment for stomach ache, abdominal pain, and chronic anaemia," write the authors in the report published in The New England Journal of Medicine. "Two- and-a-half hours after the administration of mannitol, the patient discharged a tapeworm that measured 6.2m."

During the two years prior to removal of the tapeworm, the doctors reported that nothing seemed unusual about the case. However, after a microscopic examination of the man's stool sample, they found an egg containing a tapeworm larvae.

They immediately prescribed him with the drug praziquantel, used when the human body has been infested with a living organism. Forty minutes later, the man was given mannitol, a cathartic drug used to induce cleansing – ie it made him use the loo, where the tapeworm was excreted.

After analysis, the beef tapeworm measured 6.2m long – three-and-a-half times the length of the average giraffe's neck. That measurement does not include the scolex either, the head of the tapeworm, which attaches to the intestine of the host.

Tapeworm egg
The doctors discovered the tapeworm egg in the stool of the patientLi and Guo, The New England Journal of Medicine

The man was seen again by doctors three months later at a follow-up visit. They reported that "the patient was asymptomatic, with recovery of appetite and weight."

Tapeworms are a type of parasitic flatworm that live in the stomach of their host. They are usually ingested as tiny eggs in undercooked or raw food, and can grow many metres long. There are few symptoms to suggest a tapeworm is present in a human, but diarrhoea, stomach ache and loss of weight have been reported.

Tapeworms are most common in developing countries, and are rare in the UK and the US. Fewer than 1,000 new cases are reported each year in the US.