Common parasites include: Pork tapeworm; Angiostrongylus cantonensis; Liver fluke, Anisakiasis; Sparganoides; Gnatostome and Lung flukes.

1. The representative delicacy of pork tapeworm: raw pork.

There was a rumor on the Internet that "there are hookworms in pork", saying that some pork contains strip-like white substances, which made people panic for a while.

However, Zhou Xiaonong, director of the Institute of Parasitic Disease Prevention and Control at the Chinese Center for Disease Control and Prevention, explained that there is no so-called pork hookworm.

Pork is really susceptible to parasitic infection with pork tapeworms, which often live in the muscles of pigs.

If a person eats pork that contains tapeworm cysticerci, they will develop into adult worms in the small intestine of the human body and excrete gestational segments (segments from which tapeworm eggs are produced) or eggs in the feces; when a person accidentally eats tapeworm eggs, they can develop in the human body.

Cysticerci develop in the body and are transferred throughout the body, leading to cysticercosis, blindness or epilepsy.

Tibetans, Bai and other ethnic minorities who have a tradition of eating raw pork are also at high risk of infection.

? Expert advice: To avoid being infected with cysticercosis, be careful when buying "rice pork", that is, pork infected with cysticercosis.

When purchasing, be sure to look carefully. "Rice pork" is generally in the shape of a capsule, that is, there are capsules the size of rice grains or soybeans in parts of fat or lean meat.

In addition, try not to eat pork from free-range pigs in rural areas. The risk of infection is relatively high. Be careful with pork that is too cheap.

From a biological perspective, most parasites and microorganisms can be inactivated through high-temperature treatment. Generally, infection can be avoided by cooking food thoroughly at temperatures above 80°C.

2. Representative delicacies of Angiostrongylus cantonensis: cold apple snails and iced flower snails.

Snails are the main intermediate host and transmission vector of Angiostrongylus cantonensis.

In 2006, an outbreak of Angiostrongylus cantonensis infection occurred in Beijing, causing 141 people to become ill.

Angiostrongylus cantonensis usually parasitizes two kinds of snails: one is the apple snail, and the other is the giant African snail.

People infected with Angiostrongylus cantonensis show symptoms such as fever and severe headache.

In addition to the above-mentioned snails, care should be taken to prevent parasitic infections as well as field snails and other snails that residents in the Jiangnan area like to eat.

? Expert advice: If processed improperly, the parasites contained in the snails cannot be effectively killed, so be sure not to use cold processing methods such as cold dressing and pickling. It is best to heat them thoroughly and steam them at high temperature until they are cooked thoroughly.

3. Representative delicacies of liver fluke and anisakis: freshwater sashimi.

Chilled sashimi dipped in wasabi and eaten raw is a summer delicacy, but freshwater fish have a high risk of parasitic infection.

The average infection rate of Clonorchis sinensis (commonly known as liver fluke) in freshwater fish in Guangdong, Guangxi, Heilongjiang and other places is higher than that in other areas.

If the water body of a freshwater fish pond is contaminated by human or cat or dog feces, the worm eggs in the feces will escape from the miracidia and enter the snails in the fish pond to parasitize and develop into cercariae. When the cercariae enter the fish body, they will form metacercariae, which will then develop.

The fillets enter the human body and eventually develop into adult worms in the bile ducts.

When adult worms parasitize in bile ducts, people will experience fever and liver pain, which are often misdiagnosed as cholecystitis. Long-term blockage may even induce cholangiocarcinoma.

Eating freshwater raw fish may also lead to infection by Anisakis, which lives in the bottom of the human stomach. It is a parasite of nematodes with a white body. If you accidentally eat undercooked fish containing larvae, you can become infected and develop symptoms.

Severe abdominal pain or allergic reaction.

? Expert advice: Liver fluke metacercariae in fish are difficult to identify with the naked eye. The easiest way is to cook the fish thoroughly to kill the parasites before eating it.

Be careful when eating freshwater fish sashimi in summer. Deep-sea fish can be frozen at minus 20°C for more than 24 hours to avoid infection with Anisakis.

In addition, there are toilets built above the fish pond, and feces are discharged directly into the fish pond. The fish in the fish pond have a high chance of infection, and the fish in it cannot be eaten raw.

4. Sparganum represents delicacies: stir-fried frogs and raw frog porridge.

Frog is deeply loved by consumers because of its unique flavor, delicious taste and high nutritional value.

However, the tiger-striped frog commonly known as "Frog" has a sparganosis infection rate of 49.08%. Common methods of stir-frying and rolling are difficult to kill sparganas.

In some areas, frog skin is even used for cosmetic purposes and stuck on the eyes and skin, causing sparganosis to infect through the conjunctiva or skin and mucous membranes, invade the central nervous system, and cause symptoms such as headaches and epilepsy.

? Expert advice: It is recommended to avoid eating wild game, especially wild frogs and snakes. Even if you want to eat it, you must fully cook it in boiling water. Low-temperature freezing can also eliminate sparganosis.

5. Representative delicacies of Gnatostome: iced eel slices and stir-fried eel.

Monopterus eel is the main host of Gnathostoma nematode. Human infection is most common when eating eel imported from Japan, Thailand and other countries.

The intermediate hosts of Gnatostome are various aquatic fleas and freshwater fish (including eels, etc.). Under the microscope, both domestic and wild eels are often parasitized by Gnatostome.