Which fungi are primarily responsible for most skin, nail, and hair infections?

The fungi primarily responsible for most skin, nail, and hair infections are Microsporum and Trichophyton. These genera are dermatophytes, a type of fungus that specifically infects the keratinized tissues of the skin, hair, and nails. Microsporum typically causes infections such as ringworm (tinea capitis and tinea corporis), while Trichophyton can lead to a variety of conditions including athlete's foot (tinea pedis) and onychomycosis (nail infections).

These fungi thrive in warm, moist environments and can spread through direct contact with infected individuals or contaminated surfaces. Their adaptation to invade and colonize human keratin means that they are particularly effective at causing localized infections in those areas of the body where keratin is prevalent, leading to the characteristic symptoms of fungal infections such as itching, redness, and scaling.

In contrast, the other options either refer to bacteria (like staphylococci and streptococci), that are not primarily responsible for fungal infections, or to antifungal medications (such as griseofulvin and itraconazole) used to treat such infections, rather than the organisms themselves. Epidermophyton is another category of dermatophyte that affects skin