Which among the following is not the causal organism for ringworm?

The correct answer is Option (4) → Wuchereria

Ringworm is a common infectious disease of the skin, nails and scalp. It is caused by fungi of three genera: Microsporum, Trichophyton and Epidermophyton. They cause dry, scaly, itching lesions and grow best in heat and moisture.

Option (1) Microsporum — A causal organism of ringworm. Microsporum is one of the three fungi named for ringworm.

Option (2) Epidermophyton — A causal organism of ringworm. Epidermophyton is another ringworm fungus.

Option (3) Trichophyton — A causal organism of ringworm. Trichophyton is the third ringworm fungus.

Option (4) Wuchereria — Not a causal organism of ringworm. Wuchereria is not a fungus. It is a filarial worm (a helminth) that lives in the lymphatic vessels and causes elephantiasis or filariasis.

NCERT Extract:
Common Diseases in Humans – “… Wuchereria (W. bancrofti and W. malayi), the filarial worms cause a slowly developing chronic inflammation of the organs in which they live for many years, usually the lymphatic vessels of the lower limbs and the disease is called elephantiasis or filariasis (Figure 7.2). … Many fungi belonging to the genera Microsporum, Trichophyton and Epidermophyton are responsible for ringworms which is one of the most common infectious diseases in man.”