Can pork tapeworm be killed at high temperatures?
The pork tapeworm is the main human parasitic tapeworm in China, also known as the chain tapeworm, pig tapeworm, hooked tapeworm, etc. In ancient medical texts it was called cunbaichong or baichong. People become infected by eating undercooked pork that contains cysticerci, and it can also parasitize human muscle, brain, eyes and other sites, causing cysticercosis. Let us take a look below at whether the pork tapeworm can be killed by high heat!
Can pork tapeworm be killed by high heat?
Pork tapeworm can be killed by high heat. The eggs of the pork tapeworm are not resistant to high temperatures, and cysticerci are killed at 54°C in 5 minutes, so ensuring pork is cooked through is enough to eliminate the worm. Moreover, when pork is kept at -12 to 13°C for 12 hours, all the cysticerci in it can be killed. Therefore, pork must be cooked thoroughly before eating, and separate knives and cutting boards should be used for raw and cooked meat.
How pork tapeworm infection occurs
1. Autoinfection: when a tapeworm patient feels nauseated or vomits, reverse peristalsis of the intestine carries gravid proglottids back into the stomach and causes infection.
2. External autoinfection: the patient accidentally ingests eggs excreted by themselves, causing reinfection.
3. Heteroinfection (external infection): caused by accidentally ingesting eggs excreted by another person.
What harms does pork tapeworm cause?
1. Subcutaneous and muscular cysticercosis: cysticerci located in subcutaneous or submucosal muscle form nodules. The nodules are round or oval under the skin, about 0.5 to 1.5 cm, with a hardness similar to cartilage; they can be felt by hand, have no adhesion to subcutaneous tissue, and are not tender. They often appear in batches and may gradually disappear on their own. When the infection is mild there may be no symptoms; when the number of parasites is large, the patient may feel muscle soreness, weakness, swelling, numbness, or present with pseudohypertrophic muscular dystrophy-like signs, etc.
2. Cerebral cysticercosis: the course of cerebral cysticercosis is slow, with onset most commonly occurring from 1 month to 1 year, and at longest up to 30 years. Epileptic seizures, increased intracranial pressure and psychiatric symptoms are the main symptoms, with epileptic seizures being the most common. Neurological and cerebral blood flow disorder symptoms include memory loss, decreased vision and psychiatric symptoms; others may include headache, dizziness, vomiting, unclear consciousness, aphasia, limb numbness, local convulsions, hearing impairment, mental disorders, dementia, hemiplegia and blindness, etc.
3. Ocular cysticercosis: cysticerci can parasitize any part of the eye. In mild cases the symptom is visual impairment, and worm movement is often visible; in severe cases blindness can occur. While intraocular cysticerci are alive, patients can generally tolerate them, but once the cysticerci die, the decomposition products of the worm can cause strong irritation, leading to changes in intraocular tissues, vitreous opacity, retinal detachment, optic nerve atrophy, complicated cataract, secondary glaucoma and so on, ultimately causing eyeball atrophy and blindness.