Which of the following microorganisms can be absorbed through intact human skin?

• A. Escherichia coli
• B. Staphylococcus aureus
• C. Schistosoma larvae
• D. Influenza virus

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the structure and function of intact human skin as a barrier. The skin acts as a physical and immunological barrier that prevents most microorganisms from entering the body through intact skin.
2. Step 2: Review the characteristics of each microorganism listed: Escherichia coli and Staphylococcus aureus are bacteria that typically require a break in the skin or mucous membranes to enter; Influenza virus primarily infects respiratory tract mucosa, not through intact skin.
3. Step 3: Learn about Schistosoma larvae (cercariae), which are parasitic flatworm larvae capable of penetrating intact human skin by releasing enzymes that break down skin proteins, allowing them to enter the bloodstream.
4. Step 4: Compare the modes of entry for each microorganism and identify which one is known to penetrate intact skin naturally, which is Schistosoma larvae.
5. Step 5: Conclude that among the options, only Schistosoma larvae can be absorbed through intact human skin due to their specialized invasive mechanism.