Siberian feline fluke: description, life cycle and treatment

There are more than 21 million people living on the Earth infected with Siberian cat litter. More than half of the total number of infected live in the post-Soviet space, including in Russia and Ukraine. Mass damage is typical for the inhabitants of the Siberian region and the Dnieper region. What is this parasite and how to avoid infection? And most importantly, how to get rid of "uninvited guests."

Short description

Medicine conventionally divided the parasites of the human body into three types. They are ribbon and round worms, as well as flukes. Siberian fluke is a subspecies of a lanceolate fluke, that is, a flat fluke (trematode). The Latin name of this parasite is Opisthorchis felineus and Opisthorchis viverrini. A small hepatic parasite causes a disease in humans and animals, opisthorchiasis, which affects the ducts of the liver, gallbladder and pancreas.

Siberian cat litter has a lanceolate shape. The length of the parasite does not exceed 18 mm, and the width - 2 mm. In the life cycle, two intermediate hosts are involved. The final host of a trematode can be a person or carnivore.

History of the discovery

The name "Siberian fluke" was first used in April 1891 in the city of Tomsk. Professor Vinogradov performed an autopsy and found in the liver an unknown kind of flukes. Somewhat later, information appeared, this parasite had already been described, but it was found in the liver of a deceased cat. However, the scientist who conducted the autopsy failed to determine the type of trematode.

Correctly systematized and described the parasite scientist Blanchard. This happened in 1885. This time the name "cat's fluke" was used. A disease called opisthorchiasis.

To determine the medical significance of the Siberian fluke, in parallel in different countries worked many famous scientists. For example, only for the proof that opisthorchiasis is associated with eating freshwater fish, it took almost 10 years. Various assumptions were also made about the first intermediate host of the parasite. Hans Vogel produced experimental evidence of gastropod snails. A Russian scientist Starobogatov found that these are mollusks from the genus Codiella.

Where is opisthorchiasis spread?

Siberian fluke, belonging to the subspecies of trematodes Opisthorchis viverrini, is most common in Southeast Asia. It causes opisthorchiasis in residents and visitors of Cambodia, Thailand, Laos, and Vietnam. Sometimes cases are recorded on the territory of Europe and America. They are all related to the supply of infected fish.

Siberian fluke, belonging to the subspecies of trematodes Opisthorchis felineus, is most common in the territory of the post-Soviet countries. It causes foci of opisthorchiasis in Russia, Ukraine, Kazakhstan, along the basins of large rivers. The maximum incidence rate is observed along the Ob and Irtysh rivers. Infected with a parasite pools of the Volga, the Urals, the Kama, the Don, the Dnieper, the Dvina and so on.

How the pathogen develops

Liver fluke Siberian fluke, the life cycle of which occurs in the body of several hosts, is able to develop only near fresh water bodies. The cycle of development in the organism of the first intermediate host begins, which is the freshwater gastropod mollusks-bitinids. Take these mollusks to the genus Codiella. A favorite habitat for such living creatures is a dry shoal in the floodplains of rivers. The gastropod mollusk swallows the eggs of the Siberian fluke from the contaminated water, into which the feces of the final host have fallen. Within two months in the body of the mollusk the parasite is transformed from eggs to cecaria.

Caulk of the fluke is a free-floating bisexual larva with a swimming tail. Leaving the first owner, the larvae are introduced into carp fish tissue. Here the next stage of development from the cecaria to the metacecarium occurs. The larva discards the now unnecessary tail, and creates around itself a protective capsular shell - a cyst. Inside the capsule, the larva remains mobile. From the moment of getting into the body of carp fish, until the ability to infect humans and carnivores occurs, it takes about six weeks. Only at the stage of metacycary the parasite can take root in the human body.

The final owner of the fluke becomes a person or any animal that has eaten the invasive fish. Getting into the initial department of the small intestine, metacycaria get rid of the cysts and penetrate the bile ducts, gall bladder and liver.

How does the infection occur?

Siberian fluke achieves sexual maturity in the body of the final host in 10-14 days. From this moment begins laying eggs, which with feces return to the environment. If the eggs hit the ground, they will die within 8-10 days. If in the water, then they will remain viable for almost a year. In the final host, opisthores live up to 20 - 30 years.

The next circle of the life cycle of the cat's fluke begins with the moment when a new gastropod with water and silt swallows the egg of the parasite. This vicious circle will not be interrupted while a person is eating lightly salted, half-baked or dried fish from fresh water.

Symptoms of opisthorchiasis in humans

Opisthorchias develop asymptomatically for a long time. All the symptoms of the disease in humans are associated with the mechanical and allergic effect of fluke. Allergies are caused by the products of vital activity of opisthorchia. A mechanical effect is associated with injuries to the walls of the ducts, to which the mouth and abdominal suckers of helminths are attached. In addition, the accumulation of trematodes complicates the flow of bile, causing inflammation.

The incubation period of opisthorchiasis is no more than three weeks. Further, the temperature may rise, there may be pain in the muscles and joints, vomiting and diarrhea will begin. The patient will increase the liver and spleen, there will be pain in these organs.

Symptoms will vary depending on the stage of the opisthorchiasis. In the acute stage, allergic reactions prevail. In the chronic stage - mechanical damage to the duodenum and liver, causing pain.

Symptoms of opisthorchiasis in cats

At the initial stage of helminthiosis, it is almost impossible to understand that a pet is ill. As the disease develops, the cats lose weight, the coat becomes disheveled and untidy, the mucous membranes and skin become icteric. There are also constipation or diarrhea and vomiting. The belly of a cat increases, with palpation of the liver there is pain and anxiety.

Siberian fluke: treatment

To confirm opisthorchiasis, examine the faeces and duodenal contents of the patient. In addition, appoint endoscopy, x-rays or ultrasound. For complex treatment, use anthelmintic drugs, funds for normalizing the work of the digestive tract and drugs to improve immunity. In the acute phase, the patient may be prescribed detoxification. Treatment is desirable in an outpatient setting.

Prevention of opisthorchiasis

To avoid infection with cat's Siberian fluke, you need to fulfill simple requirements:

• Do not use poorly processed freshwater fish.
• Do not feed domestic and wild animals raw fish.
• Do not pollute the water with feces.

As you can see, everything is simple. You can keep your health if you are careful and attentive.