Warts are typically caused by which virus?

• A. Human papillomavirus
• B. Cytomegalovirus
• C. Adenovirus
• D. Rhinovirus

Answer: (A)

Warts occur when skin cells are infected by human papillomavirus, a virus that targets keratinocytes in the epidermis and stimulates their growth, leading to the rough, raised lesions we recognize as warts. HPV has many strains, and certain ones cause common warts on the hands and feet, while others lead to plantar, flat, or genital warts. Transmission happens through skin-to-skin contact or contact with contaminated surfaces. The other viruses listed are associated with different illnesses—cytomegalovirus with systemic or congenital infections, adenovirus with respiratory or ocular infections, and rhinovirus with the common cold—so they don’t typically cause warts.