Any trematode parasitic in vertebrate blood vessels is called schistosomiasis. Vertebrates refer to mammals such as humans and mammals (cattle, sheep, horses, pigs, dogs, cats, rats, etc.). ). There are many kinds of Schistosoma japonicum, among which 19 is related to human diseases. Among them, Schistosoma japonicum, Schistosoma aegypti, Schistosoma Mekong, Schistosoma japonicum and Schistosoma hominis are the five species that cause schistosomiasis in people and animals. Schistosomiasis japonica is prevalent in China.
2. Where is schistosomiasis endemic?
Schistosoma japonicum is highly pathogenic and widely distributed, including Japan, China, the Philippines and Indonesia. According to the anatomical analysis of ancient corpses unearthed in the Western Han Dynasty, it is confirmed that schistosomiasis japonica existed in China as early as 2000 years ago. In China, it is mainly distributed in the Yangtze River basin and its southern provinces such as Hunan, Hubei, Jiangxi, Anhui, Jiangsu, Sichuan and Yunnan, but schistosomiasis is not prevalent in these areas, and some counties in various provinces are endemic areas.
3. What harm does schistosomiasis do to the body?
Schistosomiasis is the main parasitic disease that seriously harms the health of our people. It has a history of more than 2000 years since the discovery of schistosomiasis patients in ancient corpses of the Western Han Dynasty. Before liberation, many people died of schistosomiasis, and some villages were destroyed by schistosomiasis. Patients with schistosomiasis may have no symptoms in the early stage, and may also have symptoms such as abdominal pain, diarrhea, bloody stool and fatigue. However, people generally don't pay attention to it. If it is not checked and treated in time, it will be repeatedly infected for a long time and gradually form chronic advanced schistosomiasis. Children suffering from schistosomiasis will affect their growth and development. They are short, mentally retarded and look like little old men. Women suffering from schistosomiasis have irregular menstruation, which affects their fertility and lacks fun in life; If it develops into advanced schistosomiasis, there will be abdominal ascites, hepatosplenomegaly, bulging belly and skinny bones, and some will vomit blood, which will seriously affect labor production and life, and it is impossible to get rich through labor. The harmfulness of schistosomiasis is the "five lives" that affect life, production, life, growth and fertility.
IV. Life history of Schistosoma japonicum
The development and reproduction of Schistosoma japonicum includes five stages: adult, egg, cercaria, cercaria and larva. Adult Schistosoma japonicum is parasitic in mesenteric vein of human or mammal, and some eggs are excreted with feces, hatched in water, and then drilled into snails to develop into cercaria. When cercaria meets human or mammal, it invades its skin to form larvae, and then moves to mesenteric vein to parasitize and develop into adults.
5. What is epidemic water?
Epidemic water refers to Schistosoma japonicum cercariae in ditches, fields and ponds in schistosomiasis endemic areas. If people and animals come into contact with epidemic diseases, they will be invaded by cercariae, which will lead to schistosomiasis.
6. How is schistosomiasis spread?
When people and animals come into contact with water containing Schistosoma cercariae, cercariae will quickly enter people and animals, and after about 37 days, it will develop into adult Schistosoma japonicum, parasitic in mesenteric blood vessels, and feed on blood to maintain life.
Female insects lay eggs in the blood vessels of mesenteric veins. Eggs contain metacercariae, and each female lays about 1000 eggs every day. These eggs are so small that they can only be seen with a microscope. Eggs will release toxins and affect health; Eggs flow to the intestinal wall with blood flow, which can break through the intestinal wall and enter the intestinal cavity, and be discharged with stool.
Feces containing schistosome eggs pollute the water source. When the water temperature is about 25℃, after about 4 hours, the miracidium in the egg breaks out of its shell and swims rapidly in the water. When they meet snails, they will quickly get into snails and breed in snails, forming a large number of cercariae. Oncomelania snails with cercaria contact with water, and cercaria constantly escapes into the water. People and animals are infected by contact with cercaria in water, thus getting schistosomiasis.
In this way, schistosomiasis circulates repeatedly, constantly endangering people's lives and health.
Seven, what are the main ways of human infection with schistosomiasis?
There are two main ways of infection: one is productive infection. Such as farm work, seedling raising, transplanting, harvesting, irrigation, flood control and drainage, fishing, shrimp catching, mowing, etc. The second is life-related infection. For example, washing clothes, washing vegetables, swimming, washing hands and feet in water infected with schistosomiasis.
8. What is a snail?
Oncomelania hupensis the only intermediate host of schistosomiasis. This is an hermaphrodite amphibious snail. The shape is conical, the length is generally not more than 1cm, and the width is generally not more than 4 mm The surface of the snail shell has longitudinal edges, generally 6-9 spirals, which are mainly distributed in the range of 1m above and below the waterline of beaches and ditches (mainly small agricultural ditches). Oncomelania hupensis mainly distributed near the water inlet and ridge of paddy field.
Nine, how to prevent schistosomiasis?
The prevention and treatment of schistosomiasis is the first, followed by treatment. Prevention is to find ways to prevent schistosomiasis infection and prevent schistosomiasis in people and animals; Treatment is to treat people or livestock who have already suffered from schistosomiasis.
Avoid contact with water containing Schistosoma cercariae. During the epidemic season of schistosomiasis, people and animals should not wash clothes in rivers, ponds, ditches and ponds with snails, and primary and secondary school students should pay special attention not to play and bathe in these places. If you have to work in these snail environments, you should take certain protective measures, such as wearing rubber boots, gloves or applying anti-mite cream on your body to avoid skin contact with water.
Actively eliminate snails. Killing snails is the most fundamental measure to prevent schistosomiasis infection. Without snails, schistosomiasis would not spread. Kill Oncomelania hupensis, one is drug killing; Second, combined with the basic construction of farmland water conservancy, new ditches are opened to fill old snails.
Actively check and treat schistosomiasis. To know whether you have schistosomiasis, you should actively accept schistosomiasis examination. Primary and secondary school students are inspected at school, and adults are inspected by epidemic prevention personnel at home. At present, there are many inspection methods, such as fecal incubation test, intradermal test, indirect agglutination test and egg-circling test. After the diagnosis of schistosomiasis, no matter whether there are symptoms or signs, it should be treated in time. At present, the drug used for treatment is called praziquantel, which has low toxicity, good curative effect and convenient administration.
X. What is acute schistosomiasis?
Acute schistosomiasis often occurs in the first infected person who has no immunity to schistosomiasis infection, but a few patients with chronic or even advanced schistosomiasis can also occur after being infected with a large number of cercariae. Theoretically, any first-time infected person should show acute infection, but in clinic, only some infected people show acute schistosomiasis, which may be related to the difference of infection degree and the individual response of the body to the disease.
All patients with acute schistosomiasis have a clear history of contact with infected water. It usually happens at the turn of spring, summer, autumn and winter, and many people get sick in summer and autumn. With June-10 as the peak. The infection modes are swimming, paddling and shrimp fishing. Weeding the lake and planting grass, harvesting summer grain and flood control are the main measures. In particular, I asked about the medical history in detail. Up to now, there are still very few remote mountain villages in schistosomiasis endemic areas that have not yet found out whether schistosomiasis is prevalent.
After several hours of contact with epidemic water in schistosomiasis endemic areas, papules the size of millet to soybean appear, itchy but not painful, and disappear within several hours to 2-3 days. This is cercarial dermatitis, which can be caused by two kinds of cercariae, one is Schistosoma japonicum cercariae, and the other is non-human Schistosoma cercariae. There is no difference between cercarial dermatitis recorded in clinical history.
Incubation period: the average time from contact with epidemic water to clinical symptoms (mainly fever) is about 40 days. The incubation period is related to the severity of infection. The shortest incubation period is 14 days and the longest is 84 days, with an average of 4 1.5 days. Most cases occurred 35 days after mating and spawning of Schistosoma japonicum, when the miracidium in the eggs matured and a large number of egg antigens appeared in the blood. In a few cases, the incubation period is shorter than 25 days. At this time, there are no eggs in feces, and its acute symptoms may be caused by metabolites during the development of juvenile worms.
Fever: Fever is the main clinical symptom of acute schistosomiasis, and it is also an important basis for judging the condition. The degree and duration of fever are related to the degree of infection and the immune state of the body. Other systemic symptoms are usually parallel to fever. Typical cases have a sudden increase in body temperature in the afternoon and a fever in the middle of the night, and the temperature difference can be as high as 4℃. Fever can be roughly divided into three types: ① low fever, accounting for about 1/4 cases, also known as mild. Generally, the body temperature rarely exceeds 38℃, and the systemic symptoms are mild. You can often reduce your fever by yourself. This kind of fever often occurs when chronic schistosomiasis is repeatedly infected. ② Intermittent and relaxed patients account for the majority, especially intermittent patients, also known as intermediate patients. A typical person's body temperature rises in the afternoon, and his high fever can reach 40℃ at night. After midnight, the body temperature drops to normal or below 38℃, often accompanied by chills, sweating, dizziness and headache. There are few times when I feel cold and irritable. I feel good about myself after the fever has gone down. ③ Missing fever type, accounting for about 5%, which belongs to heavy type. The body temperature is kept at about 40℃, with a small fluctuation range, which may be accompanied by toxic symptoms such as mental retardation, lethargy, delirium and relative bradycardia.
The duration of fever in acute schistosomiasis varies from several weeks to several months. The symptoms of toxemia in fever stage of acute schistosomiasis are often not obvious, and the self-feeling in non-fever stage is still good. Some light and medium-sized patients can spontaneously reduce fever and turn into chronic phase even without special treatment. Severe patients generally can't reduce their fever by themselves. If left untreated, emaciation, anemia, malnutrition, edema and ascites may soon occur, leading to death.
Gastrointestinal symptoms: the appetite of patients with acute schistosomiasis may decrease to varying degrees, and a few of them have nausea and vomiting. Diarrhea is more common, defecating 3 ~ 5 times a day, and in severe cases it can reach 20 ~ 30 times a day, often with mucus and blood. In severe cases, the feces are jam-like, accompanied by abdominal pain, occasional abdominal tenderness and hyperactivity of bowel sounds. Some patients may have constipation, and a few patients may have ascites. Its etiology is different from that of ascites due to advanced schistosomiasis, which may be caused by the extensive formation of acute egg granuloma in liver and intestine, which leads to the increase of portal vein pressure in hepatic sinus, the increase of intestinal lymphatic exudate and leakage into abdominal cavity.
Respiratory symptoms: Cough is another important symptom of acute schistosomiasis, and about 50% cases have cough. Mostly dry cough, less phlegm, and occasionally blood in sputum. When auscultating the lungs, I can occasionally smell a little dry or wet rale.
Hepatosplenomegaly: The vast majority of patients with acute schistosomiasis see hepatomegaly, and the left lobe is more prominent than the right lobe, which can cause pain in the liver area. The examination showed that the liver was soft, smooth and soft. Hepatomegaly is generally less than 50cm below xiphoid process. Half of the patients have splenomegaly, soft quality and no compression disease.
Other signs: pale face, emaciation, fatigue, dizziness, muscle joint pain, urticaria, etc. Some cases have symptoms of thoracic schistosomiasis such as hemiplegia, coma and epilepsy.
Blood test: The vast majority of patients with acute schistosomiasis have leukocytosis and eosinophilia. The white blood cells are generally (10 ~ 30) × 109/L, and some of them are over 50×109/L. The eosinophils are generally 15% ~ 50%. Anemia and accelerated erythrocyte sedimentation rate often occur in different degrees. Some patients can see a small amount of protein in urine, but there are few casts and red blood cells. The increase of gamma globulin is more common in liver function examination, and some patients have a slight increase in ALT. Immunological examination showed that serum IgM, IgG and IgE increased, lymphocyte transformation rate decreased, and circulating immune complexes were mostly positive. The positive rate of circulating antigen in serum was 90% ~ 100%, and the positive rate of ovalbumin reaction was almost 1 00% after1month of infection. The positive rate of antibody detection by indirect hemagglutination test and enzyme-linked immunosorbent assay was close to 100%. After 5 weeks of infection, the positive rate of eggs and miracidium was close to 100% after three consecutive incubation tests. In some patients, the serum heterophilic agglutination reaction and widal reaction can be positive, so attention should be paid to the diagnosis.
X-ray examination: The X-ray examination of the lungs of patients with acute schistosomiasis varies according to the different stages of the acute stage, and there may be flocculent and fluffy point shadows, and millet shadows are rare, which are often symmetrically distributed on both sides, mainly in the middle and lower lung fields, with blurred hilum edges, increased lung texture, rough disorder and extension to the outside of the lung. The lesion disappeared for more than 3 ~ 6 months, and insecticidal treatment can accelerate the disappearance process.
Sigmoidoscopy: According to sigmoidoscopy, the main pathological changes of rectum and sigmoid colon in patients with acute schistosomiasis are congestion and edema, and the detection rate of live eggs in mucosa is 50%, which is lower than that of chronic schistosomiasis. Gland hyperplasia can cause polyps.
B-ultrasound examination: Abdominal liver of patients with acute schistosomiasis is mainly characterized by hepatomegaly and splenomegaly, and occasionally the inner diameters of portal vein and splenic vein are widened, and the echo of liver is enhanced and thickened, that is, the light spots on the screen are increased and thickened.
XI。 How to treat acute schistosomiasis?
After the diagnosis of acute schistosomiasis, you should be hospitalized immediately. Patients with body temperature above 39℃ and obvious symptoms of poisoning or severe toxemia and meningoencephalitis should be given support and symptomatic treatment before pathogen treatment.
Support and symptomatic treatment:
1, intensive care: stay in bed early, record the amount of fluid in and out for 2 ~ 4 hours, and measure blood pressure 1 time for 2 ~ 4 hours. In case of shock, measure blood pressure according to the doctor's advice and slightly lift the lower limbs to physically cool the high fever.
2. Support treatment: supplement vitamins and fluids, take vitamins B and C orally, and patients with obvious symptoms of diarrhea and digestive system may consider supplementing water, salt or energy substances. The daily infusion volume of adults is 2 000 ~ 3 000 ml, and the type of infusion should depend on the condition. If there is no obvious water loss, use 5% or 10% glucose solution 1000 ~ 2000ml, and add i0% potassium chloride I0 ml and vitamin c1~ 2g per 1000ml; For patients with high fever and hyperhidrosis, 500 ~ 1000 ml of normal saline should be supplemented daily, and the ratio of glucose to salt solution is1:1; For people with high water content and ion loss, we must pay attention to potassium supplementation. Every 500ml of 5% or 10% glucose or compound sodium chloride solution, 10ml 10% potassium chloride can be added. It is necessary to mobilize patients to take orally as much as possible, and some intravenous supplements are insufficient. Consider a small amount of blood transfusion when the condition is critical.
3. Fever: Acute schistosomiasis fever is a toxic allergic reaction caused by the strong stimulation of a large number of egg antigens. Therefore, for ordinary light and medium-sized patients, direct use of insecticidal drugs to kill worms and control the production of antigen substances can gradually reduce the fever. Praziquantel has good specific antipyretic effect on acute schistosomiasis.
Non-specific antipyretic drugs generally use corticosteroids. For patients with high fever or severe poisoning symptoms, it can be used in combination before or at the same time of pathogen treatment, which can enhance the antipyretic effect and improve the condition. Mild patients generally do not need hormone therapy; Medium-sized patients can use it for a short time, mainly orally; Hormones should be added to intravenous infusion in critically ill patients. Commonly used corticosteroids include hydrocortisone, dexamethasone and prednisone. Hydrocortisone 100 ~ 300 mg/d, added to 5% or 10% glucose solution I000ml, slowly intravenous drip; Prednisone 30 ~ 40 mg/d, 3 ~ 4 times orally; Dexamethasone 4.5 ~ 6.0 mg/d, taken orally for three times, or 10 ~ 20mg/d added to 5% ~ 10% glucose solution for intravenous injection. For patients with severe high fever, hydrocortisone or dexamethasone should be added to the infusion for intravenous drip, and taken orally after treating fever. Hormone use time should not be too long. When the body temperature drops and the symptoms improve, it can be gradually reduced and maintained for about L weeks. When corticosteroids are used, 10% potassium chloride should be taken orally at the same time, each time 10 ml, three times a day. Patients infected with strongyloides faecalis should not use hormones before effective deworming, so as to avoid immune deficiency, which will lead to spread infection of larvae, and in severe cases, patients may die.
4. Anti-shock: In case of shock, blood volume and electrolyte should be supplemented first. Patients with vomiting and diarrhea. 500 ml 10% glucose solution, 500 ml compound sodium chloride,1/0.2% sodium lactate 100 ml can be used for intravenous drip. In case of acidosis, 5% sodium bicarbonate 100 ml can be used for slow intravenous injection or drip. In toxic shock, hydrocortisone 200 ~ 400 ml/d or dexamethasone 30 ~ 40 mg/d should be added to 500- 1000ml 10% glucose solution for intravenous drip. Hormones are usually used for 2 ~ 3 days, and can be stopped after shock control. When microcirculation failure occurs, colloidal solution should be supplemented, and plasma 100-200 ml or 500 ml dextran 40 can be used. If the limbs are cold and pale, 20 ~ 40mg of mefenamin (restorative pressure sensitive) or 20 ~ 60mg of dopamine or 0.5 ~ 1 ml of isoproterenol can be added into 500ml of 5% or 10% glucose solution for intravenous drip. For patients with warm limbs and facial flushing, apply 2 ~ 5mg of norepinephrine (starting from low concentration) or 20 ~ 40mg of m-hydroxylamine (alamin) to 200ml of 10% glucose solution and slowly drip intravenously.
5. Energy supplement and anti-infection: For critically ill patients who can't eat, the daily glucose supplement should not be less than 200 g g or energy mixture should be used. If complicated with infection, antibiotics should be used in time.
6. Treatment of complex diseases: Patients with acute schistosomiasis in rural areas are often complicated with intestinal parasite infection. Before the pathogen is treated, it is advisable to treat it with insect repellent first, which can reduce the gastrointestinal reaction of pathogenic drugs; To increase the incidence of typhoid fever, dysentery and leptospirosis infection, we must first cure them with special antibiotics; If complicated with tuberculosis, praziquantel can be used to treat pathogens in time during anti-tuberculosis treatment.
7, pathogen treatment:
For light and medium-sized patients whose body temperature is lower than 39℃ and generally in good condition, pathogen treatment can be carried out as soon as possible; For severe patients with serious illness, support treatment should be given first to treat the complicated diseases, and then pathogen treatment should be carried out after the physical condition improves. Praziquantel should be the first choice for pathogen treatment. The total dose of praziquantel in the treatment of acute schistosomiasis is generally adult 120mg/kg (child 140mg/kg), and the total dose is three times a day, of which/kloc-0 is taken half on the first day and half on the second day, and half on the third to sixth day. Praziquantel works quickly. After mild patients take 1 course of treatment, their body temperature can drop to normal within 2-4 days; It takes 1 week or more for moderate or severe patients to bring their body temperature down to normal. About 50% of the patients can have Huxley-Harmo-like reactions such as chills and high fever on the day of taking the medicine, and the maximum body temperature can be increased by about 65438 0℃ compared with that before treatment, so that the body temperature "bounces". For patients with acute schistosomiasis whose body temperature has dropped to normal before taking the medicine, the dose of praziquantel can refer to the treatment of chronic schistosomiasis. For patients with fever after 1 course of treatment, if there are no other diseases, the course of 1 course can be repeated after two weeks of drug withdrawal.
Twelve, what is chronic schistosomiasis?
Acute schistosomiasis has not been cured after treatment, or has cooled itself without treatment, and has evolved into chronic schistosomiasis. When people from non-epidemic areas enter epidemic areas, they may be misdiagnosed as other diseases if they occasionally come into contact with epidemic water, have slight infection, have no acute clinical symptoms, or have only mild clinical symptoms. After half a year to about l years, there may be occult interstitial hepatitis or chronic schistosomiasis colitis, or ultrasound examination of the liver with enhanced echo and thickening changes. More common in residents of epidemic areas. Due to frequent contact with epidemic water, residents have acquired certain immunity after a small amount of infection, and they are tolerant to various antigens of schistosomiasis, especially soluble egg antigens, showing chronic schistosomiasis. Chronic schistosomiasis can be divided into the following types.
1, asymptomatic (occult)
Mainly occult interstitial hepatitis. The patient's health and labor force are not affected and there are no obvious symptoms. A few patients have mild hepatomegaly or splenomegaly, and their liver function is normal. Such patients are quite common in epidemic areas, especially in light epidemic areas. In addition, asymptomatic patients among urban residents, workers and army soldiers often need serum immune response, rectal mucosal biopsy or B-ultrasound-assisted diagnosis because they have left the epidemic area, and have less contact with infected water, fewer worms in their bodies, slight lesions and fewer fecal eggs. Asymptomatic patients have no obvious clinical manifestations all their lives, but they can also have obvious symptoms and signs due to repeated infection, drinking, malnutrition and infection with hepatitis virus.
2, there are symptoms
Mainly chronic schistosomiasis granulomatous hepatitis and colitis, the most common symptoms are chronic diarrhea or chronic dysentery. The symptoms are intermittent. Abdominal pain, diarrhea or bloody mucus are often more obvious after fatigue or catching cold. Relieve or disappear at rest. Mild diarrhea, 2 ~ 3 times a day, occasionally with a small amount of blood and mucus in the stool; In severe cases, abdominal pain and diarrhea-like feces may occur. Patients are generally in good condition and can engage in manual labor. Hepatomegaly is common, with smooth surface, slightly hard or full texture, no tenderness, and mild splenomegaly. Sometimes hard and fixed masses of different sizes can be felt in the lower abdomen. This is a fibrous granuloma, which is formed by eggs deposited in omentum, mesentery and retroperitoneal lymph nodes. This situation was common in the early days of liberation in China, mainly due to repeated infection, which did not receive timely and effective treatment. At present, it is rare and needs to be differentiated from tuberculosis and tumor. The hemogram showed eosinophilia and mild anemia. In the liver function test, except serum globulin and gamma globulin, alanine aminotransferase is in the normal range. Repeated stool examination of eggs or miracidium can get positive results. Eggs can be found in more than 90% cases of rectal mucosa biopsy, mostly denatured eggs. Serum ovalbumin reaction, indirect hemagglutination test and enzyme-linked immunosorbent assay can obtain more than 90% positive results, while 70% ~ 80% patients can detect circulating antigens. B-ultrasound can show hepatosplenomegaly and echo changes of liver parenchyma. Thickening of the vascular wall of portal vein branches is helpful for diagnosis.
Thirteen, the treatment of chronic schistosomiasis?
Most patients with chronic schistosomiasis have no obvious symptoms. The purpose of treatment is to kill adult Schistosoma japonicum in vivo, so as to eliminate pathogens, prevent the development of the disease, protect individual health, and control and eliminate epidemiological sources of infection.
Praziquantel is the first choice of anti-schistosomiasis drugs, and patients diagnosed by pathological examination standards such as stool examination and rectal mucosal biopsy are generally treated. Patients with positive serum immune reaction such as COPT, IHA and ELISA can also be considered for treatment. Praziquantel tablets 200 mg each. There are two common treatments: ① The usual treatment method is that the total dose of adults is 60 mg/kg (the total dose of children weighing less than 30 kg can be increased by 70 mg/kg), and the treatment is between meals, 2-3 times a day. Those who weigh more than 60 kg still take the medicine at 60 mg/kg without increasing the dose. ② In large-scale treatment in epidemic areas, the total dose of adults is 40 mg/kg body weight 1 day, and the total dose is taken 1-2 times. During taking medicine and within 3 ~ 5 days after taking medicine, you should pay attention to rest, reduce physical labor and avoid working at high altitude and on water. Can be treated in local medical institutions; In large-scale treatment, if there is no contraindication of praziquantel, medical staff can also send the medicine to the door for monitoring, strengthen follow-up after taking the medicine, and deal with the side effects in time.
XIV. How can residents in epidemic areas prevent schistosomiasis?
Residents in epidemic areas have frequent contact with epidemic water in their production and living activities, so management must be strengthened and prevention work must be done well. First, set up warning signs and publicity posts for schistosomiasis control in snail areas where residents have frequent activities, educate and discourage people from contacting infected water, and don't go to epidemic areas to pick zongzi leaves, pull Artemisia, weed, graze and fish shrimp. Second, due to the needs of production and life, it is really necessary to engage in planting and fishing activities in snail areas. Try to reduce the number of wading, apply protective drugs, wear protective clothing and do personal protection before entering the water; Third, educate women and children not to wash clothes and bathe with water with snails, but to use well water or tap water as much as possible; Fourth, we should take the initiative to accept the annual special inspection of schistosomiasis.
Fifteen, why should we strengthen the education and management of children?
In midsummer and early autumn, children like swimming, paddling, bathing and shrimp fishing in lakes and ditches. If they are in flood areas, they may be infected with schistosomiasis. Children suffering from schistosomiasis are not only emaciated, short and stunted, but some even become "dwarfs", which seriously affects their schooling and neglects their studies. In order to protect children's health, schools in epidemic areas should set up schistosomiasis control classes, so that children can learn and master some knowledge and protection methods of schistosomiasis control, and don't play in epidemic water. Schools and parents of children should strengthen the management of extracurricular activities, especially during the summer vacation, and students must be forbidden to graze, swim, fish and catch shrimp in epidemic areas. Formulate student protection conventions in class units, organize summer camps, schistosomiasis control knowledge contests and other activities to strengthen schistosomiasis control awareness.