Beware of infections
Blood flukes
Health tips during the flood season
Schistosomiasis is a waterborne parasitic disease in which humans and animals become infected by contact with bodies of water containing schistosomiasis cercariae (called "infested water"). Schistosomiasis japois is endemic in the Yangtze River basin and 12 provinces (autonomous regions and municipalities directly under the central government) south of it, including Shanghai, Jiangsu, Zhejiang, Anhui, Fujian, Jiangxi, Hubei, Hunan, Guangdong, Guangxi, Sichuan and Yunnan. Schistosomiasis transmission season is mainly between April and October. Schistosomiasis can be classified as acute schistosomiasis, chronic schistosomiasis, and advanced schistosomiasis based on a history of exposure to infested water, clinical manifestations, and laboratory results.
Life History of Japan Blood Flukes
01
The risk of schistosomiasis transmission increases during the flood season
High-risk behaviors for schistosomiasis infection during the flood season
The flood caused by the increase of water level during the flood season has an important impact on the epidemic of schistosomiasis, which can easily increase the frequency of human and animal contact with water bodies, increase the chance of fecal contamination of water bodies, and expand the distribution range of snails (intermediate hosts of schistosomiasis), thereby increasing the risk of schistosomiasis transmission.
Exposure to infected water increases
During the flood season, people have more opportunities to come into contact with water bodies such as flood fighting and rescue, harvesting and seeding, and if effective protective measures are not taken, they are susceptible to schistosomiasis and diseases. Schistosomiasis can also be infected by exposure to infected water through activities such as swimming, fishing, laundry, washing vegetables, etc. People in non-endemic areas of schistosomiasis and local residents without a history of schistosomiasis infection are more susceptible to acute schistosomiasis, and there are no age or sex differences. Schistosomiasis infection can also occur if you drink raw water containing schistosomiasis cercariae.
There is an increased chance of feces contaminating water bodies
During the flood disaster, the toilets and livestock pens of residents are flooded or destroyed, and the human and animal feces containing schistosomiasis eggs can hatch in the water body and infect the snails if they are brought to the breeding environment of snails by the floods, and then develop into cercariae in the body of the snails, which increases the number of snails escaping from the cercariae, which in turn causes livestock and people to be infected with schistosomiasis, resulting in the spread of diseases.
The spread of snails increases the scope of risk
Snails are the intermediate host of schistosomes, and floods in the flood season lead to flooding of water bodies, and the diffusion of snails with the flow of water causes the distribution area of snails to increase, and even forms a snail recurrence or new snail environment. Flooding inundated snail breeding environment, when the source of infection enters, can cause an increase in infectious snails, and increase the probability of human and animal infection with schistosomiasis.
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The main clinical manifestations of schistosomiasis
Acute schistosomiasis
It is caused by the first infection or the second large number of infections with Schistosoma cercariae, and the main clinical manifestations are fever, cough, abdominal pain, diarrhea, etc. The incubation period ranges from 14 days to 84 days, generally from 35 days to 42 days. If left untreated, weight loss, anemia, dystrophic edema, and ascites can develop rapidly, leading to death.
Chronic schistosomiasis
Caused by a small number of multiple infections with schistosomiasis cercariae or in patients with acute phase who are untreated or uncured. Common symptoms include fatigue, abdominal pain, intermittent chronic diarrhea, blood in the stool, and hepatosplenomegaly. Mild cases may be asymptomatic without obvious symptoms.
Advanced schistosomiasis
It is caused by repeated or large infection with schistosomiasis cercariae, which is not treated promptly and thoroughly, and develops over a long period of time. Patients often have irregular abdominal pain, diarrhea or irregular bowel movements, decreased food intake, and post-food epigastric fullness. The clinical types are megasplenic, ascites, colonic proliferative, and dwarf.
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How to prevent and treat schistosomiasis during the flood season
Avoid contact with infested water
Avoiding contact with infested water is the best way to prevent schistosomiasis. During the flood season, when the water level rises, try to avoid fishing, swimming, bathing, or washing in water bodies such as rivers, lakes, ponds, etc., which may contain schistosomiasis.
Strengthen your own protection
When contact with water bodies cannot be avoided due to flood fighting, rescue, harvesting and seed grabbing, etc., protective ointment such as anti-lux should be evenly applied to the skin parts in contact with natural water bodies before launching the water operation, and protective equipment such as rubber boots, rubber gloves, rubber pants, etc.
Avoid contact with infested water
Take personal protection
Safe water
Try to use clean and hygienic water sources and do not drink raw water. For temporary water, it can be treated with 0.5g of bleach or 1g of bleaching powder per 50kg of water, and it can be used after 30 minutes, and the drinking water must be boiled before drinking.
Take care of your stool
Schistosomiasis patients and sick animals usually have schistosomiasis eggs in their feces, and eggs can only hatch in water, so it is important to manage human and animal feces and graze them safely to prevent the feces from entering the water and block the transmission of schistosomiasis.
Timely investigation and treatment
If you come into contact with a natural water body in a schistosomiasis-endemic area and have symptoms such as fever, you should take the initiative to go to a medical and health institution for examination, and if you find an infection, you should treat it as soon as possible. Safe and effective drugs for the treatment of schistosomiasis are praziquantel, among others.
Source: Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention