Tapeworm: the characteristics of the worm

The tapeworm is a flatworm of which there are several species all belonging to the flatworm family .

It is a segmented, hermaphroditic parasite with a great reproductive capacity. Its body, whose length can even reach 10 meters, is made up of scolex, neck and a succession of different segments.

In fact, we start from the immature ones, followed by others in the process of maturing to end up with completely mature segments. It is precisely to the latter that we owe the reproductive capacity of the tapeworm.

The eggs are found in these last segments and are capable of reaching the anus to be released into the external environment through the faeces, in order to be able to propagate in other humans or vertebrates through the infestation of the intestine of the herbivores, which represent the intermediate host.

Tapeworm: how to recognize it?

It is possible to identify the tapeworm inside the animal’s meat, which presents yellowish-white cysts of variable shape depending on the affected tissue.

In some cases, thanks to this feature, it is possible to identify already visually the meat that presents some problems and the one that can be eaten safely.

To identify the presence of the tapeworm in the human intestine , on the other hand, we proceed with a diagnostic examination of the feces , thanks to which we can also trace the species of tapeworm responsible for the infection.

Inside our feces we will find segments of the worm which have a length of 1-1.5 cm, are white in color and are found on the surface of our feces.

How is tapeworm transmitted?

The various species of tapeworm have quite similar life cycles which can be summarized in the following points:

• It all starts from the segments of tapeworm in the reproductive phase which are expelled from the host’s body together with the faeces and settle in the ground or on the grass which the pigs and cattle feed on, which represent the main intermediate hosts of this parasite;
• Once they enter the stomach of the intermediate host, these segments open, thanks also to the digestive processes of the animal, and release thousands of eggs which hatch releasing a larva which takes the name of oncosphere;
• Each larva has hooks thanks to which it anchors itself to the intestinal walls and reaches the underlying tissues and the blood circulation, to feed itself in order to be able to differentiate into cysticercus, which has a length of almost one centimetre;
• The cysticercus thus infects the whole organism of the intermediate host, spreading through the blood. For this reason, if raw or undercooked infected meat is consumed, the parasite is also assumed;
• This primitive form of tapeworm is digested together with the food and in this phase the scolex attaches to the walls of the intestine starting to lengthen producing various segments. After only three months from the infection the tapeworm will have already reached half of its total length and the first segments in the reproductive phase will begin to detach from the main body;
• These segments can reach the outside by migrating by themselves up to the anus, or they can be expelled with the faeces, starting a new cycle.

There are cases where humans ingest the eggs and not the cysticercus. This occurs mainly in underdeveloped countries of the world, where there are unfortunately not optimal hygienic conditions. The eggs are absorbed in the intestine and reach the peripheral tissues through the bloodstream. Once hatched, the cysticercus is formed which is able to reach and infect all organs, including the brain, causing an infection called cysticercosis, much more common in animals than in humans.

It is rare that eggs are ingested, generally man is infected by a premature form of tapeworm, which once established in the intestine can survive for several years, and this is evidence of the fact that there is no defense system in our body account this parasite, most likely because all the symptoms are confined to the intestine and no response from the immune system is triggered.

What are the symptoms of tapeworm infection?

The most common symptom that testifies to the presence of tapeworm in the intestine is excessive and unjustified weight loss .

Nausea is also associated with this symptom, often accompanied by constipation or even diarrhea with abdominal pain. Not infrequently it happens to notice the segments in the feces or on the undergarments, a phenomenon that creates considerable psychological discomfort for the patient.

Let’s not forget, however, that the ingestion of eggs causes cysticercosis, the symptoms of which differ according to the sites where the cysticercus settles. This type of infection is seen in animals, although it is rarely identified and its diagnosis is often accidental. The herbivores affected by the infection are irritable, have epileptic crises, paralysis especially of the retina, syncope in the terminal stages.

How do you cure tapeworm?

Once the presence of tapeworm in the intestine has been ascertained, the doctor will develop the most appropriate therapeutic scheme to eradicate this parasite.

Anthelmintics are used , which generally act in the intestine without creating unwanted systemic effects as they are not absorbed and therefore do not reach other tissues.

Niclosamide works by killing the scolex and first segments which are then excreted in the stool. Mebendazole , another drug used in tapeworm therapy, acts with a different mechanism because it blocks the entry of glucose into the parasite which stops feeding and dies.

Often laxatives are also associated in order to facilitate the expulsion of the worm fragments with the feces.

How to protect yourself from tapeworm infection?

As previously mentioned, the tapeworm infects humans who eat raw or undercooked meat. Therefore it would be advisable to consume cooked meat or previously placed in a blast chiller . Thanks to this method, the foods to be eaten raw are subjected to very low temperatures to favor the killing of bacteria and other parasites.

Another way to protect yourself from tapeworms is to buy meat from a trusted retailer or in any case check for the absence of visible cysts before consuming it.