Desert rheumatism is caused by
**Core Concept**
Desert rheumatism, also known as chiggers or scrub itch, is a skin condition caused by an allergic reaction to the bites of certain arthropods. The condition is characterized by intense itching, redness, and small bumps on the skin.
**Why the Correct Answer is Right**
The correct answer is due to the bite of chiggers, which are the larvae of a type of mite. Chiggers inject saliva into the skin, causing an allergic reaction that leads to the characteristic symptoms of desert rheumatism. The saliva contains an enzyme called chigrid, which breaks down the skin's keratin layers, allowing the chigger to feed on the skin's cells.
**Why Each Wrong Option is Incorrect**
**Option A:** is incorrect because it is not related to desert rheumatism.
**Option B:** is incorrect because it is a type of skin condition caused by a fungal infection, not an arthropod bite.
**Option C:** is incorrect because it is a type of skin condition caused by an allergic reaction to urushiol, a chemical found in poison ivy, oak, and sumac.
**Clinical Pearl / High-Yield Fact**
It's essential to note that chiggers are most active in warm, humid environments and are typically found in areas with tall grass and weeds. To prevent desert rheumatism, it's crucial to wear protective clothing and apply insect repellent when spending time outdoors in areas where chiggers are prevalent.
**Correct Answer: D. Chiggers.