A Full Analysis of the Dangers, Symptoms and Treatment of Schistosomiasis

Schistosomes are parasites whose adult worms live in the blood vessels (portal-mesenteric venous system) of humans and many kinds of mammals. In the human body, schistosomes live an average of 4.5 years, with a maximum lifespan of 46 years. Sowhat dangers do schistosomes pose to the human body? What symptoms does schistosomiasis cause? How is it treated?

What are schistosomes?

Schistosomes are also called blood flukes. Schistosomes parasitize most vertebrates, and their eggs pass through the vein wall into the bladder and are excreted with urine. The larvae develop inside the intermediate host snail. Mature larvae enter the final host through the skin or mouth. Schistosoma mansoni lives in the veins of the large and small intestine and is mainly distributed in Africa and northern South America. Its eggs are excreted with feces. The larvae enter the snail, then return to the final host through the skin. Schistosoma japonicum is found mainly in mainland China, Japan, Taiwan, China, the East Indies and the Philippines, and besides humans it also infects other vertebrates such as livestock and rats.

The intermediate host of schistosomes --- the Oncomelania snail

Transmission routes of schistosomiasis

The transmission routes of schistosomiasis mainly include the whole process of eggs entering water, miracidia hatching out, invading the Oncomelania snail, cercariae escaping from the snail and invading the host. Among all the links in the transmission of schistosomiasis, three are important: feces containing schistosome eggs contaminating water bodies, the presence of Oncomelania snails in water bodies, and people coming into contact with infected water (water containing cercariae).

In which season is infection with schistosomes most likely?

Infection with schistosomes can occur in all four seasons, but it is most likely from April to October.

The main ways of schistosome infection

First, occupational contact with infected water, such as fishing for fish, catching shrimp, grazing and fighting floods in infected water; second, domestic contact with infected water, such as washing clothes in infected water; third, recreational contact with infected water, such as swimming, playing in the water and playing in infected water.

The main dangers of schistosomiasis

Schistosomiasis is an infectious and parasitic disease caused by humans or mammals such as cattle, sheep and pigs becoming infected with schistosomes, and it seriously harms people's health.

Patients suffering from schistosomiasis may have no symptoms in the early stage, or may have symptoms such as abdominal pain, diarrhea, blood in the stool and fatigue, but generally people do not pay attention to them. If timely examination and treatment are not obtained, over a long period of time and with repeated infection, chronic advanced schistosomiasis gradually develops; if a child suffers from schistosomiasis, it affects growth and development, so the child does not grow tall and has low intelligence, looking just like a little old man; if a woman suffers from schistosomiasis, her menstruation becomes irregular, fertility is affected, and she lacks joy in life; if it develops into advanced schistosomiasis, ascites will form in the abdominal cavity, the liver and spleen enlarge, the belly is as big as a drum while the person is thin as a stick, and some will also vomit large amounts of blood. Truly, one can eat but cannot work, and work and life are seriously affected; getting rich through labor is simply impossible. The harm of schistosomiasis is that it affects the “five lives”: life, production, living, growth and reproduction.

Symptoms of schistosomiasis

Treatment of schistosomiasis

Actively get examined and treated for schistosomiasis. After examination confirms schistosomiasis, treatment should be given promptly whether or not there are symptoms or signs. The drug currently used for treatment is called praziquantel; it has low toxicity, good efficacy and is convenient to take.

Methods and measures to prevent and control schistosomiasis 

① Do not swim, play in the water, cut grass, fish, catch shrimp, wash clothes, wash vegetables or engage in other activities involving contact with infected water in lakes, ponds and canals where Oncomelania snails are present, and do not drink unboiled water.

② When contact with infected water is necessary for production, daily life or flood control, measures such as applying protective ointment and wearing protective equipment should be taken to prevent infection with schistosomes.

③ After contact with infected water, promptly go to the local hospital or schistosomiasis control institution for examination and early treatment, and people found to be infected should actively receive treatment under a doctor's guidance.

④ People living in endemic areas should actively cooperate with the snail surveys, snail elimination, disease screening and treatment work carried out by the local schistosomiasis control institutions, as well as the screening and treatment of livestock.

⑤ Improving water supply and toilets, preventing feces from contaminating water sources, ensuring the safety of drinking water, and changing production and living habits that are harmful to health are important measures to prevent the spread of schistosomiasis.

The best way to prevent schistosomiasis is not to come into contact with infected water. If contact with infected water is unavoidable for production, the following protective measures can be taken: (1) apply protective products (such as fangyouling and fangyou cream) before contact with infected water; (2) wear long rubber boots, nylon protective trousers, gloves, etc.; (3) after contact with infected water, take preventive drugs orally such as artesunate and artemether.