Host Description: A. lumbricoides only host is humans, but mostly children. Children have a higher risk of getting infected because they are more likely to play in soil than adults. Also boys are more likely to get infected than girls. When comparing US to the rest of the world, 4 million Americans have been reported to have these worms. On an international level 1.4 billion people have been infected with these worms . Some patients have been known to have only a few worms which are easily treatable. But in some cases there can be hundreds of worms in patients causing extreme pain and gastrointestinal trauma .