Can intestinal parasites (worms) in feces transfer to humans through direct contact?

From the Guidelines

Yes, worms in poop can transfer to humans through contact with contaminated fecal matter, typically through the fecal-oral route. This transmission can occur when microscopic worm eggs present in feces contaminate hands, food, or surfaces that are then touched by another person who inadvertently ingests the eggs 1. Common intestinal parasites transmitted this way include pinworms, roundworms, and hookworms. The primary mode of transmission for enteric pathogens, including intestinal worms, is the fecal-oral route, where contaminated animal fur, hair, skin, and saliva can lead to transmission when persons pet, touch, feed, or are licked by animals 1.

To prevent transmission, thorough handwashing with soap and water after using the bathroom and before handling food is essential, as recommended by the MMWR Recommendations and Reports 1. If worm infection is suspected, medications like albendazole (400mg single dose for most adults) or mebendazole (100mg twice daily for 3 days) are typically prescribed, though specific treatment depends on the parasite type. Family members of infected individuals often require simultaneous treatment to prevent reinfection. Regular cleaning of bathroom surfaces, washing bedding in hot water, and maintaining good personal hygiene are important preventive measures.

Key factors that increase the risk of disease transmission include lack of awareness of the risk for disease, inadequate hand washing, lack of close supervision, and hand-to-mouth activities, especially in children 1. The layout and maintenance of facilities and animal exhibits can also increase or decrease the risk for infection, with inadequate hand-washing facilities, inappropriate flow of visitors, and incomplete separation between animal exhibits and food preparation and consumption areas being significant risk factors 1.

Overall, preventing the transmission of intestinal worms through human-to-human contact involving fecal matter requires a combination of good personal hygiene, proper handwashing, and awareness of the risks associated with contact with contaminated fecal matter.

From the FDA Drug Label

PINWORM: Pinworms look like tiny white threads and live in the bowel. Usually at night, they travel to the rectal opening and lay eggs on the outside skin. This sometimes causes itching which may be very annoying. That is why restless sleep is a frequent sign of pinworms, especially in children. Scratching will cause pinworm eggs to stick to the fingers Reinfection will result if the fingers are placed in the mouth. The eggs, which are too small to see, contaminate whatever they come in contact with: bedclothes, underwear, hands, and food touched by contaminated hands. HOOKWORM, WHIPWORM AND ROUNDWORM: These worms also live in the bowel. Eggs from the worms are deposited in the soil if an infected person fails to use a toilet or bathroom. In the case of hookworms a pre-adult form of the worm actually penetrates the skin (usually the foot) and burrows its way into the bloodstream.

Yes, worms in poop can transfer to humans through contact.

• Pinworm eggs can stick to fingers and be transferred to the mouth, causing reinfection.
• Hookworms can penetrate the skin, usually through the foot, and enter the bloodstream. This information is based on the drug label for mebendazole 2.

From the Research

Worms in Poop and Human Contact

• The transfer of worms from poop to human contact is a complex issue, and there are several factors to consider.
• According to 3, humans can be exposed to pathogens from poorly managed animal feces, which can include worms.
• The study 3 also identifies routes of contamination by animal feces, including water, sanitation, and hygiene (WASH)-related pathways.
• Another study 4 emphasizes the importance of hand hygiene in preventing the spread of disease, which can include worms.

Prevention and Control

• Effective hand hygiene practice is crucial in preventing and controlling infection, as stated in 4.
• The use of anthelmintics, such as albendazole, mebendazole, and ivermectin, can help treat and control worm infections, as discussed in 5, 6, and 7.
• However, the reliance on a few drugs creates a dangerous situation for the development of resistance, as mentioned in 7.

Transmission and Health Risks

• Exposure to animal feces has been associated with various health risks, including diarrhea, soil-transmitted helminth infection, and growth faltering, as reported in 3.
• The study 6 provides information on the treatment options and considerations for intestinal helminthic infections, which can be transmitted through human contact with contaminated feces.
• It is essential to note that the transmission of worms from poop to human contact can occur through various routes, including contaminated food, water, and soil, as mentioned in 3.