As the weather gets hotter, crayfish start to become a regular on people's tables. Thirteen spices, spicy, dry stir-fried ...... There's even crayfish sashimi!
CDC is very worried about the hidden risks behind this way of eating, and a large number of visible lung flukes appeared after the crayfish were cleaned on the Internet, which was really creepy.
Simplified version
Lung fluke disease is a zoonotic foodborne disease, lung fluke can parasitize the body of crayfish, food should be noted:
1. Wash well before cooking.
2. Do not eat raw, cook at a temperature of 100°C or above for at least 10 minutes, and cook thoroughly.
3. Don't eat dead shrimp and don't eat shrimp heads.
What are the facts? Let's start with the growth history of lung flukes.
History of lung flukes
Parmenimiasis is a zoonotic foodborne disease. 1
3. Adult lung flukes parasitic in the lungs of humans or animals produce eggs, enter the stream with sputum or feces, develop into larvae after 3-6 weeks at a suitable temperature, and burrow into freshwater snails such as the first intermediate host, the snail Chuanjuan. 2
3. After 2-3 months of asexual reproduction, a large number of cercariae escape and burrow into the second intermediate host, freshwater crabs or crickets, to form cysts. 3
3
After the cyst is ingested into the human body, the cyst wall is dissolved in the stomach and duodenum through the action of digestive juices, and the larvae pass through the jejunum into the abdominal cavity, and then through the diaphragm, and migrate through the chest cavity to burrow into the lungs.
So humans or animals are the definitive hosts of lung flukes.
The origin of crayfish and lung flukes
The main route of human infection with lung flukes is ingestion of a second intermediate host, freshwater crabs or crickets. The scientific name of the cricket is Northeast black shrimp, which is distributed in northern Liaoning, Changbai Mountain, Jilin and Yalu River in China. The crayfish we usually eat, the scientific name is Crayfish cruchi, which is a different species from the cricket, mainly distributed in the middle and lower reaches of the Yangtze River and the ditches south of the Yangtze River.
However, there are literature or studies that have reported the discovery of eggs or cysts in crayfish. Why is that? Most of the crayfish eaten by the public come from artificial farming. Compared with natural environments such as muddy ditches, artificially farmed crayfish are relatively clean, but different breeding environments will also cause differences in crayfish. For example, high levels of algae or water bodies that are raised using feed may cause crayfish to attach more impurities. Moreover, there are various parasites in freshwater, and crayfish can be infected by lung flukes in water bodies.
Therefore, if the conditions for transmission are met, the risk of contracting paragonimiasis by eating crayfish cannot be ruled out.
Hazards of paragonimiasis
If you have paragonimiasis, the clinical symptoms will vary depending on the site of the parasite, and the main manifestations are cough, chest pain, sputum production, and larval migransis. The larvae travel through various parts of the body to damage important organs, and metabolites cause immunopathological reactions. For example, "tunneling" between lung tissues destroys normal tissue structures; In the mind, "havoc in heaven" can paralyze, loss of sensation, aphasia, epilepsy, and even fatality.
What should I pay attention to when eating crayfish?
If you want to enjoy the delicious taste of crayfish, please make the following three points first! 1
Wash – Wash repeatedly with clean water
If you cook it yourself, wash the crayfish first. Crayfish can be reared in clean water and constantly washed until the water is clear.
2
Cooking – Do not eat raw, cook and cook thoroughly
Never eat crayfish sashimi or underripe crayfish!
The temperature of cooking crayfish needs to reach more than 100°C and last for more than 10 minutes to achieve the effect of high temperature disinfection. It is recommended not to stir-fry, because this may not be fried thoroughly and unevenly, and live eggs are still left in the crayfish's body. It can be fried in oil and then stir-fried, and boiling is also a good choice.
3
Edible – do not eat dead shrimp and do not eat the head
If the shrimp after cooking has a strong fishy smell, the shrimp body is loose and straight, the flesh is soft and inelastic, the color is darkened, and the shell has more sticky substance, it is likely to be a dead shrimp.
When eating crayfish, you should avoid eating the head, because the head contains organs such as the liver, stomach, and gills, which are prone to accumulate many pollutants, including parasites.
TIPS crayfish has a certain nutritional value, in addition to high protein content, it is also rich in magnesium, zinc, iodine, selenium and other trace elements, but high uric acid, gout, bad stomach or physical deficiency and cold constitution and allergies to aquatic products should not be greedy.
Source: Shanghai CDC
Editor: Li Bingqian
Editor-in-charge: Wang Bo
*Please indicate the source of the reprint from "Shanghai Changning"
If you like it, just like it
Welcome to leave a comment and interact with "Ningning".
Give me another little flower that is "watching"~