Ascaris lumbricoides

ascariasis, infection of humans and other mammals caused by intestinal A. suum, can also cause Ascaris worms often are asymptomatic, heavy infestation can cause severe complications, particularly in children, who may experience In humans, ascariasis involving A. lumbricoides develops following the ingestion of fertilized eggs that have contaminated foods or soil. In the

Ascariasis is a parasitic infection of the intestine caused by the roundworm Ascaris lumbricoides. Millions of people are infected with the worms, but often they do not have symptoms and will not have severe complications. Ascariasis is common in people who do not have access to clean water or proper sanitation. The Centers for Disease Control and Prevention (CDC) estimate that approximately 800 million to 1.2 billion people are infected with Ascaris lumbricoides. The highest rates of infection are in Asia. Ascariasis Causes People become infected with Ascaris lumbricoides by accidentally ingesting eggs found in human feces. Humans can also be infected with a roundworm from pigs called Ascaris suum. The symptoms are the same. It is unknown how many people worldwide are infected with this parasite, but it is not as common as infection with Ascaris lumbricoides. Ascariasis Treatment Several antiparasitic agents are effective against ascariasis. However, taking these medications does not prevent reinfection and, according to several studies, reinfection with the parasite happens quickly after treatment. This is why it's essential to practice proper hygiene and environmental sanitation. Ascariasis is not very common in the United States. But, if you have traveled to an area where the disease is common, have potentially come into contact with contaminated soil and water, and see worms in your stool, see your healthcare provider. Summary Ascariasis is a parasitic infection of th...

Geographic Range Ascaris lumbricoides infections have been reported in more than 150 countries across the globe, particularly in tropic, subtropic and temperate regions. Approximately 1.4 billion people worldwide are infected, 4 million of whom live in the United States. As an obligate internal parasite of humans, Ascaris lumbricoides can theoretically be found wherever humans are present. The highly durable eggs can remain dormant in the soil for up to 10 years and are resistant to many adverse conditions. ( • Biogeographic Regions • • • • • • • • Other Geographic Terms • Habitat The roundworm, Ascaris lumbricoides is an obligate internal parasite and adults usually reside in the small intestine of humans, specifically the jejunum. The worm produces a pepsin inhibitor to prevent host enzymes from digesting it and uses muscular activity to avoid being excreted. The life cycle involves no free-living stages or intermediate hosts, although fertilized eggs require up to 3 weeks of embryonation in soil before becoming infective and can survive for up to 10 years in soil under warm, moist conditions. As part of the life cycle, larva briefly migrate via the circulatory and lymphatic systems through the liver, heart and lungs. Rarely the worms may migrate to other regions of the body including the appendix, pancreas, kidneys or brain. Temporary infections can be induced in other mammals (rodents), but following migration through the liver and lungs the larvae are expelled from th...