Adult worms can grow more than a foot long. Infection occurs from contaminated food or water. It’s rare in the United States but may occur in the rural Southeast. AscariasisĪscariasis is an infection of Ascaris lumbricoides and affects more than 800,000 million people in the world. Most people infected with hookworms have no symptoms. They were once common in the United States, particularly in the Southeast, but they’ve become less common as living standards have improved. It’s estimated that between 576 to 740 million people are infected with hookworms. They’re easily passed between people living in close quarters.

It’s estimated that more than 1 billion people in the world are infected with pinworms, and they’re the most common type of worm that infects humans in North America. Flukes are most common in East and Southeast Asia.

Humans can become infected by eating contaminated food or water. They range from a fraction of an inch to several inches long. More than 70 types of flukes can live in the human intestinal tract.

Tapeworms as long as 25 meters (82 feet) have been found in humans. It’s thought that fewer than 1,000 people in the United States are infected with tapeworms each year, although the exact number isn’t known. Humans get tapeworms by eating raw or uncooked pork or beef. roundworms, which cause ascariasis, pinworm, and hookworm infections.flatworms, which include tapeworms and flukes.Common types of intestinal worms that can infect humans include:

Black flat worms