Consider the following statements :

1. Taeniasis is an intestinal infection caused by three species of tapeworm— Taenia solium, Taenia saginata and Taenia asiatica.

2. When cysts develop in the brain, the condition is referred to as neurocysticercosis (NCC).

Which of the above statements is/are correct?

Question

UnlockIAS · Accepted Answer

Correct — C, Both 1 and 2. Both statements are lifted almost word for word from the World Health Organization's fact sheet on taeniasis and cysticercosis, and both stand exactly as written. Statement 1: under "Transmission and burden" the fact sheet opens "Taeniasis is an intestinal infection caused by 3 species of tapeworm: Taenia solium (pork tapeworm), Taenia saginata (beef tapeworm) and Taenia asiatica." All three produce an adult worm in the human intestine and all three cause mild, non-specific symptoms — abdominal pain, nausea, diarrhoea or constipation — appearing about eight weeks after the infected meat is eaten, and an untreated T. solium infection generally persists for two to three years. WHO does add that only T. solium causes major health problems, and that T. saginata and T. asiatica have no major impact on human health, but that qualifier does not touch the statement: the claim is about what causes taeniasis, and three species do. Statement 2: the same fact sheet says the larvae, called cysticerci, may develop in the muscles, skin, eyes and central nervous system, and that "when cysts develop in the brain, the condition is referred to as neurocysticercosis (NCC)" — the statement is that sentence. The term is not a nicety. WHO calls neurocysticercosis the most frequent preventable cause of epilepsy worldwide, estimated to cause 30 per cent of all epilepsy cases in countries where the parasite is endemic and up to 70 per cent in specific high-risk communities where people and roaming pigs live close together; between 2.56 and 8.30 million people are estimated to be living with NCC, and its symptoms run from chronic headache and seizures to hydrocephalus, meningitis and blindness. Since neither statement contains an error, the answer is both.

Why the other options are wrong — (a) Accepts the three species but rejects the brain terminology, usually because a candidate is unsure whether the condition is called neurocysticercosis or something built on the word taeniasis. It is neurocysticercosis, and WHO uses that exact wording — cysts in the brain, NCC in brackets. The term also carries the whole clinical weight of the parasite: imaging is the gold standard for diagnosing it, WHO has issued dedicated guidelines on its management, and it lies behind a large share of adult-onset epilepsy in endemic regions, which is why the World Health Assembly's Resolution 68.20 of 2015 on epilepsy is part of the response to this worm.  (b) Rejects statement 1, almost always because the candidate has learned only two tapeworms — pork and beef — and treats the third name as invented. Taenia asiatica is a genuine third species, recognised from East Asia and transmitted through inadequately cooked pig liver tissue rather than muscle meat, and WHO lists it in the same sentence as the other two. The temptation is strengthened by a real fact half-remembered: WHO does say only T. solium causes major health problems. But "causes no major health problem" is not "does not cause taeniasis", and the statement makes only the second claim.  (d) Requires both statements to be wrong, but both reproduce WHO's published wording. The only route to this option is to confuse taeniasis with cysticercosis and then reject each statement for a fault that belongs to the other — deciding, for instance, that statement 1 must be about cysts because tapeworms are dangerous, and that statement 2 must be about the gut because taeniasis is intestinal. Separating the two diseases, and remembering that they arrive by two different routes, removes the temptation entirely.

Concept: Taenia is a cestode — a segmented flatworm of the phylum Platyhelminthes with a head, the scolex, bearing suckers and, in T. solium, a crown of hooks, followed by a chain of proglottid segments. It has no mouth and no gut and absorbs nutrients straight through its body wall, and each proglottid is hermaphrodite. The life cycle needs two hosts. The human is the definitive host, carrying the adult worm in the intestine; the pig or the cow is the intermediate host, in which swallowed eggs hatch and the larvae encyst as cysticerci in muscle. Eating undercooked infected meat completes the loop and gives a human taeniasis. The dangerous variant happens when that cycle is short-circuited: if a person swallows T. solium eggs directly — by the faecal-oral route, through contaminated food or water, or where open defecation lets eggs into the environment — the human becomes an accidental intermediate host, and larvae encyst in that person's own tissues. That is cysticercosis, and in the brain it is neurocysticercosis. The public-health shape of the disease follows from that two-host cycle. Because the parasite passes between people and pigs, no purely medical intervention can end it; WHO's package is explicitly One Health, pairing treatment of human carriers with vaccination of pigs using the TSOL18 vaccine and treatment with oxfendazole, an end to open defecation and to free-roaming pigs, and better meat inspection. It is also a disease of poverty: it concentrates in subsistence farming communities in Africa, Asia and Latin America, and it destroys the market value of the pigs those households depend on.

State PCS 2023 Q4 — Science & Technology PYQ with Answer

State PCS 2023 Q4 — Science & Technology PYQ with Answer