A girl who is staying in a hostel presented with severe itching all over the body since two days. Intense itching worsens at night and after a hot shower. Burrows are seen between the fingers. How many live mites are there in an adult with scabies?
**Core Concept**
Scabies is a parasitic skin infestation caused by the mite Sarcoptes scabiei. The female mite burrows into the skin, causing intense itching, especially at night and after a hot shower. The presence of burrows between the fingers is a classic sign of scabies.
**Why the Correct Answer is Right**
The female mite lays eggs in the burrow, which hatch into six-legged larvae. The larvae then molt twice, developing into eight-legged nymphs. The first nymph stage is the most infective stage, but the question asks about the number of live mites in an adult with scabies. In an adult with scabies, the number of live mites is approximately 10-15 mites per square inch of skin. However, the question asks for the number in an adult with scabies, implying a person who has developed immunity and has a low mite population. The correct answer is 10-15 mites, but the actual figure is much lower due to the immune response. However, since there is no exact figure available for an adult with scabies, we consider the number in an adult with scabies to be around 10-15 mites, but this number may not be accurate for an adult.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it is an extremely low number of mites for an adult with scabies.
**Option B:** This option is incorrect because it is an extremely high number of mites for an adult with scabies.
**Option C:** This option is incorrect because it is a number that is typically associated with the number of mites in an infant or young child with scabies.
**Clinical Pearl / High-Yield Fact**
In scabies, the immune response causes a significant reduction in the number of live mites. The number of mites in an adult with scabies may be as low as 10-15 mites per square inch of skin, but this number is not always accurate.
**Correct Answer: B. 20-50 mites.**