What is Ascariasis?
Ascariasis is a disease caused by the parasitic roundworm Ascaris lumbricoides. Infections have no symptoms in more than 85% of cases, especially if the number of worms is small. These may be followed by symptoms of abdominal swelling, abdominal pain and diarrhea. Children are most commonly affected, and in this age group the infection may also cause poor weight gain, malnutrition and learning problems.
Infection occurs by eating food or drink contaminated with Ascaris eggs from feces. The eggs hatch in the intestines, burrow through the gut wall, and migrate to the lungs via the blood. There they break into the alveoli and pass up the trachea, where they are coughed up and swallowed. The larvae then pass through the stomach for a second time into the intestine where they become adult worms. Ascariasis is classified as a neglected tropical disease as it is a type of soil-transmitted helminthiasis. These diseases are in turn part of a group of diseases called helminthiasis.
Prevention is by improved sanitation, which includes improving access to toilets and proper disposal of feces. Reoccurring infections are common. Treatments recommended by the World Health Organization are the medications albendazole, mebendazole, levamisole or pyrantel pamoate.
About 0.8 to 1.2 billion people globally have ascariasis with the most heavily affected populations being in sub-Saharan Africa, Latin America, and Asia.