Which one is an incidental parasite

Options

A. Taenia solium
B. Echinococcus granulosus
C. Schistosoma haematobium
D. Ancylostoma duodenale .

Answer

To determine which of the given options is an incidental parasite, we need to understand the definition and characteristics of incidental parasites. Here’s a step-by-step solution:

### Step 1: Understand the Definition of Incidental Parasite
An incidental parasite, also known as an accidental parasite, is a type of parasite that establishes itself in a host but does not complete its life cycle in that host. Instead, it typically requires another host to thrive and reproduce.

### Step 2: Analyze the Given Options
We have four options to consider:
1. **Tinea solium** - Also known as the pork tapeworm, it lives in the intestines of pigs and can infect humans when they consume undercooked pork.
2. **Echinococcus granulosis** - This is a tapeworm that primarily lives in the intestines of canines (like dogs) and can infect humans through accidental ingestion of eggs from contaminated sources.
3. **Cystoma hematobium** - This is a blood fluke that lives in the urinary tract of humans and is not an incidental parasite.
4. **Encyclostoma duodenale** - This is a roundworm that causes intestinal infections in humans and is not an incidental parasite.

### Step 3: Identify the Incidental Parasite
- **Tinea solium** is not incidental since it completes its life cycle in pigs and humans.
- **Cystoma hematobium** is not incidental as it lives in humans.
- **Encyclostoma duodenale** is also not incidental as it causes infections directly in humans.
- **Echinococcus granulosis**, on the other hand, is an incidental parasite because it primarily lives in dogs and can infect humans when they are exposed to the eggs, typically through contaminated food or water.

### Conclusion
The correct answer is **Echinococcus granulosis**, as it is the only option that fits the definition of an incidental parasite.

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