Parasites of humans

definition

Parasites are small living things that attack another living thing in order to be able to feed and / or reproduce. In microbiology, in connection with humans or animals infested by the parasite, the "Host" spoken. The life of the host can be affected by the parasite, but there are usually no deaths. If a person is infected with a parasite, one speaks of a parasitosis. Parasites can also be transmitted from animals to humans. Then one speaks of one Zoonosis.

Parasites can settle in or on different areas of the body. As an ectoparasite, they are on the body, for example on the skin or hair, as an endoparasite, they are in the body, i.e. in the intestine or in the bloodstream. A parasite infestation in humans often goes unnoticed at first and the symptoms only appear after a while.

What types of parasites are there?

There are many different types of parasites. They can be broken down in several ways.

  • Structure in unicellular (Protozoa) and multicellular Parasites (Metazoa), to which the worms belong.
  • Breakdown by settlement location in living on the skin (Ectoparasites) and living in the body (Endoparasites) Parasites.
  • Breakdown into stationary and temporary parasites according to the duration of the infestation. Stationary parasites live continuously on or in their host, like lice. Mosquitoes, on the other hand, are among the temporary parasites that only visit the host at certain times, for example to eat.

Causes of Parasites

The most common cause of transmission is contaminated food or drinking water. Raw meat in particular is often responsible for transmission. However, the parasites can also be passed on from person to person, as well as from animals to people. The risk of parasitic transmission increases precisely where there is close contact between humans and animals and where there are poor hygienic conditions.

People with poor intestinal flora are more likely to be infected if they come into contact with parasites, e.g. in the form of spoiled raw meat or contaminated drinking water. Likewise, a sugary diet provides the parasites with plenty of food and promotes their settlement in the human intestine.

A strong immune system should actually prevent parasites from nesting through the formation of special antibodies. However, some parasites have developed survival strategies that make it impossible for the immune system to act against them. For example, they change their surface structure so that they are no longer recognized as a parasite or they release certain substances that suppress the immune system. So they can nestle in people undisturbed and use them as hosts.

Symptoms

Parasites can affect almost any region of the body. They can appear in the bloodstream, settle in muscles, or affect organs. Even the brain can be affected. Often the symptoms are not directly associated with a parasite infestation because they are very unspecific. The symptoms usually only appear some time after the parasite infestation.

Depending on the place of settlement, the most varied of symptoms can occur. Inflammation can occur in the organs, which can even become chronic and lead to an overreaction of the immune system, which can damage the organ.

Since the parasites feed on humans, the infected person usually suffers from a lack of nutrients. Parasites also excrete toxic metabolic products that can put a strain on the digestive system or the immune system.

  • Intestinal infestation: If the intestine is infested with worms, for example, this often leads to flatulence, constipation or diarrhea.
  • Skin involvement: this often leads to redness and itching
  • Respiratory tract infection: possible symptoms are coughing or shortness of breath
  • Urinary tract involvement: this can lead to incontinence
  • CNS attack: seizures or impaired consciousness can occur here

Find out more about the topic: Typhus

diagnosis

Since most parasites affect the intestines, the diagnosis is often by one Stool sample deliver. As a rule, if a parasitic infestation is suspected, a stool sample is examined. This must be on several days be carried out in order to obtain a meaningful result. But also by one Blood test parasites can be diagnosed. Here you can with an infestation special antibodies prove against the parasites.

At Lice (head lice or Pubic lice), which are also parasites, can usually be diagnosed as Eye diagnosis be provided (see: Red spots on the scalp).

Where can parasites be found in the body?

Parasites can settle in very different places in the body. There the infected region varies with the genus of the parasite. If there is an infestation with parasites, these can often be detected in the stool or blood. You can find them among many others, for example:

  • In the intestine
  • Under the skin
  • In the brain
  • In the chair
  • In blood

Parasites in the intestines

Parasites that settle in the intestine are primarily worms (intestinal leeches, tapeworms, roundworms, roundworms, pinworms, and many more). Almost every second person harbors parasites in their intestines, but this infestation often goes unnoticed as it does not cause any symptoms.

Parasites can easily get into the intestines through contaminated food or drinking water. They are often transmitted, especially through raw meat. But parasites can also get into the intestines through insects, pets or other people (for example through sexual intercourse). Parasites that penetrate the human body through the skin can reach the intestines via the bloodstream and lodge there.
Some parasites can penetrate the colon wall and get into the bloodstream. This enables them to spread throughout the body. In the intestine, the parasite infestation mainly leads to symptoms such as flatulence, constipation or diarrhea.

Read more on this topic at: Worms in the intestines

In order to be able to detect parasites in the intestine, a stool examination is usually carried out. Often, however, no parasites can be detected despite the parasite infestation, as these hide in the mucous layer of the intestine or in so-called diverticula (protuberances) and thus do not get into the stool. The stool should be examined over several days in order to obtain a meaningful result. A blood test can also determine whether antibodies against certain parasites have been formed.

When a person is infected with parasites, it is important to strictly observe hygiene. In particular, thorough hand washing after using the toilet and after playing with pets should be considered. In addition, the pets should be checked regularly for parasites.
Worms in the intestines can be treated with anti-worm drugs. A colon cleansing program often helps against the parasites in the intestines. In addition to cleaning the intestines, the immune system is also strengthened and the risk of renewed parasite infestation is reduced.

Parasites in the eye

Parasites can attack various parts of the body. This includes the eyes. One of them is the nematode Onchorcerca volvulus, which is found in Africa and some countries in South America. It is transmitted by the black flies that can be found in bodies of water, which is why the disease that is triggered is also known as river blindness. After infection, the parasites migrate through the connective tissue of the skin to the eye.

Those affected often remain symptom-free for over a year. The first signs are more frequent itching, which gets worse and eventually develops into dermatitis, i.e. inflammation of the skin. The death of the individual parasites in the skin causes an inflammatory reaction.

Once in the eye, the nematode causes keratitis with subsequent scarring. In addition, the eye nerve is affected and the nerve fibers die off. All in all, these changes lead to blindness in the affected person.

According to statistics, this is the second most common infection-related cause of blindness in the world. The parasite can be easily removed with the help of medication, but the infestation is often only noticed late, for example when the eyesight is already deteriorating and irreversible damage has occurred.

Parasites in the nose

The nose can also be attacked by parasites. The parasite from the genus Leishmania attacks the mucous membranes of the nose, but also the mouth or throat and causes the infectious disease leishmaniasis.

Ulcers can develop and sufferers report frequent nosebleeds and difficult nasal breathing. The nasal septum can be damaged by inflammatory processes, which is why drug therapy is necessary.

Another parasite called Naegleria fowleri uses the nose as an entrance to the brain, where it can cause immense damage.

Both types of parasites occur mainly in warm, humid areas of Africa or America.

Parasites in the liver

The liver is a popular organ for various parasites. Parasitosis of the liver mostly occurs after a stay in tropical areas.

Schistosomes, for example, live in bodies of water and can pierce their way through the skin to get to their host.

In the body, they first lay eggs in the veins of the intestine, which are then washed into the liver via the portal vein, where they cause liver damage.

The liver fluke Fasciola hepatica, in turn, enters the body via the oral route. As soon as the larvae colonize the liver, they develop into leeches up to 3 cm in size.

These can lead to hepatitis, cirrhosis of the liver, and inflammation of the pancreas.

Parasites in the lungs

The lungworm Paragonimus westermani is mainly found in Southeast Asia and, as the name suggests, affects the lungs.

It finds its way into humans via freshwater crabs and crayfish, which is why the consumption of raw shellfish carries a certain risk and can lead to an infestation.

After the worms arrive in the duodenum, they penetrate the intestinal wall and diaphragm until they reach the lungs. There the parasites encapsulate themselves and begin laying the eggs. Those affected suffer from pulmonary paragonimiasis, which causes unspecific symptoms such as chills, fever and diarrhea. As the disease progresses, blood is repeatedly coughed up.

Parasites in the bladder

The schistosomes already mentioned in the above section can also attack the bladder, where they implant themselves in the veins. The eggs laid there cause a strong immune response in the body. Bladder wall tissue is destroyed and scarred, often causing bleeding. Evidence of this is provided by blood found in the urine of those affected.

The severe destruction of the urinary tract ultimately causes incontinence. This clinical picture is known as bladder bilharzia and is the most common parasitic disease after malaria.

Parasites under the skin

Some parasites enter the body through the skin by boring into the upper layers of the skin and settling there.

This is the case, for example, with scabies. This disease is caused by mites that dig ducts in the skin. Soft, thin and moist areas of skin are mainly affected, such as the spaces between the fingers or the genital area (see: Eczema in the genital area). There is very severe itching, which usually occurs at night. Mites can be transmitted through body contact or through laundry. Mites are treated by applying special creams.

Read here which symptoms cause scabies: Symptoms of scabies

There are also so-called house dust mites; some people are allergic to these mites. Unlike the mites that cause scabies, these bed mites do not cause a rash.

The so-called "skin mole" also settles under the human skin. They are larvae of the hookworm that can be transmitted to humans by dogs or cats. Humans are not a suitable host for the larvae. Nonetheless, they dig passages under the skin of humans, causing severe itching and redness. Sometimes blisters also form on the skin. The larvae can be killed by applying certain creams.

Read more on the subject at: Itchy rash.

When infested with fly maggots, the blowflies lay their eggs on the mucous membranes or in wound secretions. The larvae hatch from the eggs and penetrate the skin. Painful lumps develop under the skin.

Parasites in the brain

Parasites can also penetrate the brain via the bloodstream. More than half of all people have antibodies against the parasite Toxoplasma gondii (toxoplasmosis), which have arisen from previous contact with the toxoplasmosis pathogen. The parasite can be transmitted to humans through cat feces or raw meat.

Toxoplasma gondii affects the hormone production of dopamine in the brain. This has an impact on human movements and behavior. The infestation is noticeable through long-lasting flu-like symptoms. It is discussed whether the pathogen may play a role in diseases such as schizophrenia, Parkinson's or ADHD.

Parasites in the stool

If a patient complains of symptoms such as diarrhea, constipation or flatulence and no cause is initially found, the stool can be examined for parasites. The infestation of the intestine by intestinal parasites can be the cause of these unspecific complaints. In order to get a meaningful result, the stool is examined for several days, as some worms cannot be detected directly in the initial phase.

If parasites are found in the stool, an appropriate therapy to combat the intestinal parasites (often worms) must be initiated. Various drugs are suitable for this. In addition, an intestinal rehabilitation is a possibility to restore the normal healthy intestinal flora.

Parasites in the blood

When the parasites are up in the bloodstream are located, so you can usually antibody against the parasites in the Blood test Find. This is carried out if no parasites can be found in the stool sample if a parasite infestation is suspected. In addition, one must Malaria suspected a blood test for parasites will be done.

If the parasites are in the bloodstream, they can reach almost any organ in the human body and cause damage there.

Therapy of parasites

Since there are many different types of parasites or parasite infestation, there are also different therapeutic approaches.

At Head lice using one is enough special shampoos and using a Nit comb to remove the parasites. Usually these can be purchased in the pharmacy.

Against worms there are special ones Medicines for wormsthat kill the worms. Also one Intestinal rehabilitation can be helpful to restore the normal intestinal flora and to strengthen the immune system. This prevents a new worm infestation.

Against parasites that the Organs affected and / or yourself in the bloodstream there are special ones Tabletsthat kill the parasites. Medicines that counteract a worm infestation must be from after the diagnosis Doctor prescribed become.

It is about Parasiteswho the Skin affected therapy often consists of the application of Anoint or Creamsthat are applied to the skin. Here, too, a doctor must have clarified the exact cause or the parasitic disease beforehand in order to initiate adequate therapy.

What does a parasite test look like?

There are different test methods depending on the type of parasite. In the case of intestinal parasites, the stool is often checked for parasites by a laboratory. For other types of parasites, however, blood tests or skin samples can be taken.

What is tested depends on the symptoms. If you suspect a parasite infestation, it is usually advisable to see a doctor first. Various tests for self-implementation are also offered on the Internet. In most cases, a stool sample is taken and sent in special packaging to a laboratory, which examines the stool sample for a number of parasites. However, this does not replace specialist treatment by a competent doctor.

What is a parasite cure?

A wide range of so-called parasite cures can be found on the Internet. Mostly it is initially stated that a large number of parasites and those infected by them can also be found in Europe.

The infestation with parasites is anything but harmless, but can lead to dangerous diseases such as cancer, depression or high blood pressure. Common symptoms are said to be gastrointestinal problems or fatigue and cravings.

Since many of the parasite cures are controversial, it is questionable whether they can help against a real parasite infestation. The products offered are often a mixture of black nut shells, wormwood and cloves. The inventor of this cure, Dr. Clark, is scientifically highly controversial, the drugs offered are usually expensive.

Here you can find out everything about the topic: Parasite cure