Which one of the following diseases is non-infectious?

Elephantiasis

The correct answer is Option (4) → Elephantiasis

Cholera: Infectious disease

• Caused by the bacterium Vibrio cholerae. Spreads through contaminated water and food.

Pneumonia: Infectious disease

• Caused by bacteria like Streptococcus pneumoniae or viruses. Spreads through droplets from coughs/sneezes.

Tuberculosis (TB): Infectious disease

• Caused by Mycobacterium tuberculosis. Spreads through airborne droplets.

Elephantiasis: Non-infectious in terms of person-to-person transmission.

• Caused by parasitic worms (Wuchereria bancrofti) transmitted by mosquitoes, not through direct human contact. Hence, it is vector-borne and not directly infectious between people.