Doctors film microscopic worms dancing inside man's scrotum

A man suffering from pain and inflammation in his genitals had parasitic worms dancing inside his scrotum, and doctors caught them on video.

The man, a 26-year-old living in New Delhi sought medical attention after experiencing pain and swelling in his testicles, along with minor fevers, for around a month. After conducting a quick ultrasound scan, doctors spotted multiple parasitic worms packed inside his scrotal skin.

Blood analysis revealed that the beasties were juvenile Wuchereria bancrofti, a type of parasitic nematode, or roundworm,  found in tropical regions and transmitted between humans through mosquito bites. The worms have life spans of up to eight years and, upon developing into adults inside human lymphatic vessels, will mate to produce millions of wriggling offspring called microfilariae. 

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These young go on to migrate around the body, causing the inflammatory disease known as lymphatic filariasis, which can result in severe swelling of the legs, arms, breasts and genitals. 

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The researchers documented the discovery of the microscopic worms in a report published in The New England Journal of Medicine (opens in new tab) Dec. 8.

"The dance sign represents the undulations of live worms," the doctors wrote. "[They] have migrated into lymphatic channels, causing dilation and dysfunction of the channels."

More than 120 million people are infected by lymphatic filariasis worldwide at any given time, according to The Pan American Health Organization (opens in new tab), with 40 million disfigured or disabled by the disease. Infections tend to begin in childhood, with symptoms manifesting later in life that can lead to physical disabilities and mental, social and financial hardship such as depression, stigma and poverty.

Although in some cases surgery is needed to remove the worms, a three-week course of the antiparasitic drug diethylcarbamazine fortunately killed off the worms in this patient's case.