An outbreak of the pork tapeworm, Taenia solium, has affected at least 209 children from Thanh Khuong Commune in the northern province of Bac Ninh, according to local media.

Since last week, thousands of parents have rushed to Hanoi with their kids after news broke out that 57 children of the Thanh Khuong Kindergarten in Thuan Thanh District have been found with tapeworm infections.

To Mai Hoa, director of the Bac Ninh Health Department, said the province will coordinate with concerned agencies to test and support the cost of testing for students of 19 preschools in the area.

Late last month, pork suspected to be infected with the parasite was found in the school’s kitchen, but the actual source of the tapeworms has not been confirmed yet. Huong Thanh Financial Ltd. Co. has been identified as the food supplier to the kindergarten, as well as almost all kindergartens and primary schools in Thuan Thanh.

About 9,500 students from 19 kindergartens and 2 primary schools in the province have consumed food supplied by the company, an investigation has found.

What is the pork tapeworm?

Taenia solium is a tapeworm that people get from eating raw or undercooked “measly pork”. The pork meat has cysticerci (the larval stage) which in the human intestine mature to an adult tapeworm. Here the tapeworm attaches to the intestine and produces thousands of eggs.

Does the pork tapeworm cause disease while in the intestine?

Taenia solium scolex/CDC
Taenia solium scolex/CDC

Most people are asymptomatic and only become aware of the tapeworm by noticing segments of the worm in their feces. Symptoms of infection, if any, are general: nausea, intestinal upset, vague abdominal symptoms such as hunger pains, diarrhea and/or constipation, or chronic indigestion.

What is cysticercosis?

Human cysticercosis occurs either by the direct transfer of Taenia solium eggs from the feces of people harboring an adult worm to their own mouth (autoinfection) or to the mouth of another individual, or indirectly by ingestion of food or water contaminated with the eggs. When the person ingests the eggs, the embryo escape from the shell and penetrates the intestinal wall, gets into the blood vessels, where they spread to muscle, or more seriously, the eyes, heart or brain.

How serious is cysticercosis?

The severity of cysticercosis depends on which organs are infected and the number of cysticerci. An infection consisting of a few small cysticerci in the liver or muscles would likely result in no obvious disease and go unnoticed. Those that form in voluntary muscle tend to be asymptomatic, but may cause some pain. On the other hand, a few cysticerci, if located in a particularly “sensitive” area of the body, might result in irreparable damage. For instance, a cysticercus in the eye might lead to blindness, or a cysticercus in the brain (neurocysticercosis) could lead to traumatic neurological damage, epileptic seizures or brain swelling that can kill.

How long after infection do symptoms of cysticercosis appear?

It may be as short as a few weeks or up to 10 years or more.

Is it treatable?

It can be treated with anti-parasitic drugs like praziquantel and steroid therapy to control brain swelling. Occasionally surgical intervention may be required to relieve symptoms.

How do you prevent this disease?

Adequate cooking of meat destroys the tapeworm larvae and will prevent infection by tapeworm. Freezing meat to -5C for 4 days, -15C for 3 days, or -24C for 1 day kills the larvae as well.

Good hygiene and hand washing after using the toilet will prevent self-infection in a person already infected with tapeworms in addition to contamination of foodstuffs by human feces.