Roundworm parasitic infection in humans

Roundworms or nematodes are long, thread-like parasites that can cause infection in humans. Roundworm parasitic infections occur all over the world but most commonly in warmer climates.

Roundworms infect human intestine. These infections are mainly caused by inappropriate personal hygiene and lack of proper sanitation measures. Eggs of a female roundworm can be picked up on hands when handling contaminated water or soil. If a person eats or touches his/her mouth without washing his/her hands first, parasites easily enter the digestive tract. Eating unwashed fruits and vegetables or uncooked meat and seafood can also cause the infection to spread. Types of Roundworm Parasitic Infection

There are many types of roundworm parasitic infections. Common roundworm infections are ascariasis, toxocariasis, trichuriasis, trichinosis and anisakiasis.

Ascariasis

The most common and most severe roundworm parasitic infection is ascariasis. This infection is caused by Ascaris lumbricoides, a parasite that may reach 14 inches in length. Once the eggs are swallowed they pass into the intestine where they hatch into larvae. The larvae exit through the intestinal wall, reach the liver and move to the lungs via bloodstream.

Ascariasis leads to Loeffler’s syndrome which causes inflammation of the lungs accompanied by chest pain, shortness of breath and cough with bloody sputum. Ascariasis also causes abdominal pain, cramps, nausea and diarrhea. Toxocariasis

Toxocariasis is a roundworm infection caused by Toxocara canis and Toxocara cati, parasites that live in the intestine of cats and dogs. These pets contaminate soil when defecate and a person gets easily infected when handling this soil. Children are susceptible to this infection since they often play in sandboxes and mud.

When swallowed, eggs of the parasite release larvae in the intestine which then travel throughout the body via the blood and lymphatic system. This infection affects the lungs, heart, brain, liver and eyes. Symptoms of toxocariasis include skin rash, high fever, coughing bouts and tissue swelling known as granulomas. Swelling of the liver, inflammation of the lungs and eye infection may also occur.

Trichuriasis

Trichuriasis or whipworm infection is caused by Trichuris trichiura, a parasite which is found in warm and humid climates. This infection affects more than 800 million people each year. Mild whipworm infection is asymptomatic. However, severe whipworm infection causes abdominal cramps and dysentery. In children it leads to anemia and developmental retardation.

Anisakiasis

Anisakiasis infection occurs due to anisakid roundworms which are found in marine fish. People can get infected when eating raw or undercooked seafood. Anisakiasis causes nausea, vomiting, diarrhea and severe abdominal pain.