Schistosomiasis is a parasitic disease that, if left untreated, can have very serious consequences for your he alth. Fortunately, we have drugs that deal with dangerous microbes that cause schistosomiasis quite quickly and effectively.

Schistosomiasistakes a heavy toll. It is the largest - after malaria - parasitological problem in the world. Hundreds of thousands of people die from this disease every year. The number of patients is approximately 230 million (mainly inhabitants of Africa and South America), and in 20 million the disease is severe. It should be noted that there may be even more of these people, because in many the disease is relatively mild, or it is in the (yet) asymptomatic phase and is not reported at all.

What is schistosomiasis and how do you get sick?

Schistosomiasis, or bilharzia, is a parasitic disease caused by flukes of the genus Schistosoma. There are several species of these dangerous worms:

  • Schistosoma mansoni
  • Schistosoma intercalatum
  • Schistosoma heamatobium
  • Schistosoma japonicum
  • Schistosoma mekongi

People most often get infected withS. japonicumiS. mekongi . It happens when it comes into contact with water containing flukes. So most often when bathing in lakes or rivers.

The Schistosome Life Cycle

The path that worms have to travel to eventually cause disease in humans is extremely long, complicated and, in a way, fascinating. First, an infected animal or human sheds fluke eggs along with their faeces.

The male Schistosomal flukes are white or gray in color. Its body, 7-10 mm long and 1 mm wide, is covered with tubercles and is equipped with a genital tube in which the female resides - slightly darker and slightly smaller.

This feces must get into fresh water, because only in such an environment can flukes develop. The water from the egg hatches the miracidium, or freak, and thus the first larva in the flukes' life cycle. The oddball swims in the water in search of a suitable snail. Each species of schistosome needs a different type of snail. The snail becomes an intermediate host, thanks to which the miracidiumit turns into a parent sporocyst, which in turn turns into a daughter sporocyst, and it turns into a cercariae. Ceriakia is already such an advanced stage of the worm that it can leave the snail's body. Moving with its tail, it swims in water and looks for the ultimate host. It can become a man. Ceriac disease penetrates into the human body through the skin. It locates in superficial blood vessels. Here it goes into the next stage - the schistosomula - which, along with the blood, reaches the lungs, the left heart, the large bloodstream, and finally the liver. It is only in the liver that the Schistosoma reaches its mature, sexual form. The male is combined with the female and together they enter the venous system of the smaller pelvis, mainly the urinary bladder. Parasites multiply in venous vessels, and part of their eggs enters the lumen of the bladder or intestine and leaves the human body with urine or feces. Nature really is amazing …

Symptoms of schistosomiasis

Depending on whether the parasites and their eggs are in the liver, bladder or intestine (and sometimes in the lungs), they can cause different symptoms in their host. The first of them appear 4-6 weeks after infection and they are:

  • itching
  • blush
  • papular rash on the skin

These symptoms disappear after about 24-72 hours. The so-called Katayama fever, which is a severe allergic reaction, fever, cough, stomach pain. Those who are infected again do not have such severe symptoms. In the next phase of the disease, associated with the migration and multiplication of bacteria, there are:

  • general weakness of the body
  • poty
  • chills
  • diarrhea (often bloody)
  • hematuria
  • weight loss.

Elevated levels of eosinophils appear in the blood smear. In the last stage, the internal organs are damaged, especially the liver and spleen, ureter and bladder. Advanced, chronic schistosomiasis also leads to:

  • esophageal varices
  • hydronephrosis
  • bladder cancer
  • intestinal polyposis with bloody diarrhea
  • pulmonary hypertension
  • of portal hypertension.

Diagnosis and treatment of schistosomiasis

In order to diagnose schistosomiasis, a microbiological examination of urine and feces is required. It is the best study, but the material collected for analysis does not always contain parasites. So if we came back, for example, from a trip to a country where Schistosoma occurs, and based on the symptoms, we suspectinfection, it is worth repeating the test even several times. Additionally, serological tests are performed that detect the presence of antibodies in the blood. In addition, the following may prove the possibility of developing schistosomiasis:

  • anemia
  • hypoalbuminemia
  • elevated urea levels
  • elevated creatinine levels
  • hipergammaglobulinemia

Treatment of the disease involves taking antiparasitic drugs, with each speciesSchistosomeshaving a different substance. The drug of choice is praziquantel - two doses of 20 mg / kg body weight in one day. However, in the case ofS.mansoniinfection, oxsamnichine is recommended, in the case ofS. heamatobium- metrifonat, and in the case ofS.japonicum- oltipraz. After one month, the tests should be repeated, sometimes the treatment is also repeated.

This treatment has a very good prognosis if the infection is recognized quickly. Unfortunately, many infections are asymptomatic for a long time. In chronic schistosomiasis, when, for example, damage to internal organs has already occurred, treatment is obviously more complicated and more difficult.

Is it possible to protect against schistosomiasis?

Schistosomiasis is fairly well-controlled and successfully treated today. What is important for us is the fact that the disease is very rarely brought to Poland. However, it is worrying that while we are seeing a decline in morbidity as well as mortality, the incidence of schistosomiasis is constantly increasing. This is due to the movement of the population, e.g. related to tourism, but mainly to the migration of refugees. It seems that prophylaxis is the only effective way to fight this disease. Avoid swimming in freshwater reservoirs in areas withSchistosomesand use bottled water for drinking and preparing meals.

About the authorMarta Uler A journalist specializing in he alth, beauty and psychology. She is also a diet therapist by education. Her interests are medicine, herbal medicine, yoga, vegetarian cuisine and cats. I am a mother of two boys - a 10-year-old and a 6-month-old.

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Category:

Parasitic diseases