Can horsehair worms parasitize the human body?

Under normal circumstances, horsehair worms (Gordian worms) may parasitize the human body, but the probability of infection is low and most cases present with mild symptoms. If there has been unusual exposure or related symptoms appear, prompt medical attention is recommended. A detailed analysis is as follows:

Adult horsehair worms typically live in aquatic environments, while their larvae may enter the human body through water or food. Drinking untreated raw water, consuming undercooked insects or fish, or contact with contaminated water sources may allow the larvae to enter the digestive tract via the mouth or invade the urinary system through the urethra. Due to anatomical differences, women are at relatively higher risk of urinary tract infection.

When parasitizing the urinary tract, patients may experience frequent urination, urgency, painful urination, hematuria (blood in urine), and lower abdominal pain. When residing in the digestive tract, symptoms are mostly indigestion, abdominal pain, and diarrhea. In rare cases, the parasite may affect the eyes, external auditory canal, or throat, causing local redness, swelling, pain, or a foreign body sensation. Symptoms usually resolve after the worm is expelled.

To prevent horsehair worm infection, avoid drinking raw water or eating inadequately cooked aquatic organisms, clean the skin promptly after contact with water, and minimize direct exposure to unclean water sources during outdoor activities.