Trichinella spiralis . It is a small, threadlike dioecious nematode that causes the disease trichinosis.
Summary
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- 1Habitat
- 2 Features
- 1 Infectious larva
- 2 Newborn larva.
- 3 Biological cycle
- 4 Infections in humans
- 5 Symptoms
- 6 Treatment
- 7 Fuente
Habitat
In any mammal that eats infested raw meat, mainly carnivores and to a lesser extent in pigs, rats, humans and herbivores. Man is not an important host, however it is common in some populations where raw pork is consumed. As in Europe and the United States, it is rare in Africa and Latin America.
Features
Trichinella spiralis is a small, threadlike dioecious nematode. Males measure 1.4 to 1.6 mm long by 40 µm in diameter and have two lobed caudal appendages without copulatory spicules. The females measure 3 to 4 mm in length by 60 µm in diameter and have a blunt and rounded posterior end, they have a single ovary that is located in the posterior part and produces ovules with three chromosomes, later the uterus and then the vulva. near the middle of the sticosome, its somatic cells have six chromosomes. Males produce non-flagellated sperm, with two to three chromosomes, their somatic cells have five chromosomes. Newly hatched larvae are 120 µm long by 7 µm in diameter and have a set of cells, perhaps germ cells, but no organs.
infective larva
It has a cuticular body, oral opening, esophagus, nerve ring, stichosome, midgut, hindgut, and cloaca.
Newly hatched larva.
They represent the muscle invasion phase. It lives in the cytoplasm of the muscle cell and induces the aggregation of mitochondria, elongation of the nucleus with prominent nucleoli, hypertrophy of the glycocalyx in a thick collagen cover formed by a complex network of venules that are believed to facilitate the transport of nutrients.
Biological cycle
The same animal organism acts as an intermediate host and as a definitive host, housing the adult parasite in a short period of only a few days and the larval form for long periods of months and even years. For this parasite to continue the cycle, another organism is required to ingest the muscle mass in which said larva is housed.
human infections
Trichinella spiralis larvae enter humans through ingestion of raw or undercooked meat that harbors larvae. Digestive enzymes in the stomach digest the meat and the larvae are released, pass into the small intestine and within 10 minutes invade the columnar epithelium and lamina propria of the duodenum. In the infection process, the cuticle, the hypodermic glandular cells, the muscular and nervous system, the digestive apparatus and the sticosome are remodeled, appearing the genital primordium. Five days after infection, the female simultaneously invades 425 epithelial cells, while the male occupies 152. Copulation takes place in this intramulticellular niche in the following 40 hours and it is probable that the male moves towards the female since these they produce pheromones. Each female produces approximately 500-1, 500 live worms over a period of 2-5 weeks.
The newly hatched larvae flow through the blood and can enter any cell but can only survive in musculoskeletal cells. The larvae seem to prefer active muscles such as the diaphragm and the tongue. Most cells die as a result of larval invasion, except muscle cells. Inside a muscle cell, the worm becomes encased in a capsule and the cell is now a cyst or nurse cell that feeds the worm. This parasite behaves like a virus Most cells die as a result of larval invasion, except muscle cells. Inside a muscle cell, the worm becomes encased in a capsule and the cell is now a cyst or nurse cell that feeds the worm. This parasite behaves like a virus Most cells die as a result of larval invasion, except muscle cells. Inside a muscle cell, the worm becomes encased in a capsule and the cell is now a cyst or nurse cell that feeds the worm. This parasite behaves like a virus
Symptoms
Abdominal discomfort, colic, diarrhea, muscle pain, fever and in some cases hypersensitivity to visual and auditory stimuli occur.
Treatment
Mebendazole can be used to treat infections in the intestines. In the same way, Thiabendazole can be used in early stages of the disease. There is no specific treatment for trichinosis once the larvae have invaded the muscles. Pain relievers can help relieve muscle pain.
