Description
Ascaridosis is the most common helminthiasis; according to various estimates, about 1 billion people worldwide are infected with it. The causative agent of ascaridosis is the human roundworm (Ascaris lumbricoides), belonging to the class of roundworms. The only source of infestation (helminth infection) is humans. Infection occurs by swallowing ascarid eggs along with food. Most often, poorly washed vegetables (especially root crops) or dirty hands act as the source of infection.
The entire life cycle of ascarids takes place in the human body. From the eggs swallowed by a human, larvae emerge in the small intestine, penetrate through the intestinal wall into the bloodstream, are carried to the liver, heart, and ultimately reach the lungs, where they penetrate the alveoli through the walls of pulmonary capillaries. From the respiratory tract, the larvae migrate to the oral cavity (more often at night) and, mixing with saliva, are swallowed again. The larva, once back in the intestine, matures into an adult individual in 2.5-3 months. The total lifespan of an ascarid is about one year. In addition to the intestines, liver, and lungs, ascarid larvae have been found in the brain, eye, and other organs. Larvae, located in internal organs, feed on blood serum and erythrocytes.
Clinical manifestations of ascaridosis depend on the localization of the parasite and the intensity of the infestation. In the clinical course of ascaridosis, two phases are distinguished – early (migratory) and late (intestinal).
Symptoms of the early phase can be weakness, malaise, sometimes fever up to 38°C, enlargement of the liver, spleen, lymph nodes, and the appearance of skin rashes. The first phase coincides with the period of migration of larvae from the intestine to internal organs.
Diagnosing ascaridosis in the migratory stage is possible with the help of serological tests that detect specific antibodies (IgG and IgM) in the patients' blood. In the intestinal stage, serological testing can be supplemented by a stool examination for ascarid eggs.
The intestinal phase of ascaridosis most often proceeds with the following symptoms: signs of gastrointestinal tract damage, decreased or perverted appetite, nausea, unstable stool, and abdominal pain. Many patients report symptoms related to the nervous system: weakness, malaise, memory loss, restless sleep. Some experience epileptiform convulsions.
Period of execution
Within 7 days. The specified time does not include the day of biomaterial collection
Biomaterial type