Water host required for schistosomiasis ?
**Core Concept**
Snail species belonging to the genus *Biomphalaria*, *Bulinus*, and *Afrobrontus* serve as intermediate hosts for the parasitic flatworms causing schistosomiasis. These snails facilitate the larval development of the parasite, which eventually leads to human infection through contact with contaminated water.
**Why the Correct Answer is Right**
The correct intermediate host for schistosomiasis is a specific species of snail that harbors the larval stages of the parasite, known as cercariae. These cercariae are released from the snail host into the water, where they can penetrate human skin, leading to infection. The most common species of snail that serve as intermediate hosts for *Schistosoma mansoni* are *Biomphalaria glabrata* and *Biomphalaria pfeifferi*, while *Bulinus truncatus* is a common host for *Schistosoma haematobium*.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option would be incorrect as it is not a recognized species of snail that serves as an intermediate host for schistosomiasis.
* **Option B:** This option would be incorrect as it is not a recognized species of snail that serves as an intermediate host for schistosomiasis.
* **Option D:** This option would be incorrect as it is not a recognized species of snail that serves as an intermediate host for schistosomiasis.
**Clinical Pearl / High-Yield Fact**
It is essential to note that schistosomiasis is a water-borne disease, and the risk of infection can be significantly reduced by avoiding contact with contaminated water. In endemic areas, wearing protective clothing, including long-sleeved shirts and pants, and using insecticides to kill snails can also help prevent infection.
**Correct Answer: C. Bulinus truncatus.