Let´s talk about schistosomiasis

Hygiene and health go hand in hand, it does not mean that a person who has the best health habits can not get sick, of course, but when the habits are not the best nor the conditions where the person develops are not the best, there is a greater predisposition not only to get sick more often but also to acquire diseases that in sanitary conditions would not be possible.

Such is the case of schistosomiasis which is a disease that is more common in developing countries with inadequate hygiene conditions and lack of access to drinking water. Which is practically a public health problem, which is a product of not having a clean water source and bad habits in the collection and treatment of this.

I hope that everyone who lives in this community has a source of drinking water, which is one of the basic human rights, and that I never have to go through or know someone who goes through this situation, but if you want to know more about this disease I invite you to continue reading this publication that what I am going to tell you will surely interest you.

It is always good to start with the concept of schistosomiasis and some generalities before getting into a particular subject. Schistosomiasis is a parasitic disease caused by a worm called Schistosoma. It is transmitted to humans through water contaminated with worm eggs, and can cause symptoms such as abdominal pain, fever and diarrhea. In severe cases, it can cause damage to internal organs and skin lesions, and it is the latter that must be avoided.

The symptomatology of schistosomiasis occurs as a result of the presence and migration of adult Schistosoma worms in blood vessels and other body tissues, as well as the inflammatory response generated by the presence of worm eggs in the tissues.

This disease presents with a wide variety of symptoms, among which I would like to highlight the following:

• Abdominal pain: caused by inflammation and damage to internal organs, such as the liver and bladder.

• Fever: this is an immune system response to the presence of worms and eggs in the body.

• Diarrhea: may be caused by inflammation of the intestines and the presence of eggs in the stool.

• Skin lesions: the penetration of cercariae (I will explain later what cercariae are) into the skin can cause skin rashes, itching and swelling.

• Fatigue: inflammation and organ damage can cause fatigue and general weakness.

• Difficulty urinating: the presence of worms and eggs in the bladder may cause pain and difficulty urinating.

These symptoms may vary in intensity and frequency depending on the severity of the infection and the individual immune system response. In severe cases, schistosomiasis can cause irreversible damage to internal organs and serious complications such as liver or kidney failure. This sometimes ends up being the cause of death of the patient, especially considering that the localities where they are found are of scarce resources.

There is something very interesting from the epidemiological point of view and that is the life cycle of Schistosoma. That is the evolutionary ways it goes through and how it adapts to each space to survive and at the same time generate disease in the process.

The schistosomiasis life cycle involves two different hosts: humans and freshwater snails The cycle begins when Schistosoma eggs are excreted with the feces of an infected person and enter freshwater. There, the eggs hatch and release small larvae called myricides that seek out and enter a suitable freshwater snail.

Inside the snail, the larvae develop into sporocysts and eventually into cercariae. The cercariae leave the snail and enter the water, where they can infect a person by penetrating their skin. Once inside the human body, the cercariae travel into the blood vessels and develop into adult schistosomes.

The adult schistosomes settle in the blood vessels and begin to produce eggs, which leak into other body tissues, including the liver, bladder and other organs. The eggs can cause damage and generate an inflammatory response, leading to symptoms of the disease. Finally, the eggs are excreted with the feces and enter the water again, thus initiating the complete cycle.

The image is in the public domain.

Fortunately, treatment for schistosomiasis is relatively simple and involves the use of a specific medication called praziquantel. This drug is taken orally and works by killing the adult Schistosoma worms.

It is important to note that the treatment does not cure the infection, but simply kills the adult worms and prevents the production of more eggs. Therefore, it may be necessary to repeat treatment in the future if re-exposure to water contaminated with worm eggs occurs.

In addition to medical treatment, it is important to take measures to prevent reinfection, such as avoiding bathing or drinking water contaminated with worm eggs, and improving hygiene conditions and access to clean water in affected areas.

The latter is the most important from the point of view of treatment, because as I mentioned at the beginning, it is a PUBLIC HEALTH problem, and it is necessary to educate the inhabitants of the affected localities.

The image is in the public domain.

When I was studying, specifically in the second year of medicine, they took us to a rural town, and the experience was incredible. I had the opportunity to see this disease in some residents, and I understood that it is not only about medicines, even about education, but also about available to government entities to be able to provide the necessary services to the different towns.

I hope this publication has been of interest to you and that you are left with good information about this disease. If you have something to add, I invite you to leave it in the comments and so we all benefit.

---

• Links consulted

• Schistosomiasis - WHO

• Bilharzia: Pathology, Diagnosis, Management and Control

• CDC- Parasites - Schistosomiasis