Which conditions require contact precautions?

Contact precautions are implemented to prevent the spread of infections that can be transmitted through direct or indirect contact with an infected person or their environment. The correct response includes conditions that require these precautions due to their contagious nature or ability to persist on surfaces.

Psoriasis is a chronic skin condition and not infectious, so it does not require contact precautions. However, scabies is highly contagious and spreads through direct skin-to-skin contact, necessitating contact precautions. Clostridium difficile is a bacterium that causes severe gastrointestinal symptoms and can be spread through contact with contaminated surfaces or hands, therefore requiring contact precautions. Pediculosis, or lice infestation, is also highly contagious and can spread through close contact or sharing personal items such as hats or combs, thus requiring similar precautions.

These elements combined explain the rationale for selecting this answer, as it encompasses conditions that necessitate protective measures to prevent transmission and protect both healthcare workers and other patients.