Water-Borne Pathogens MCQ with answer and solution

Concept

Water-borne diseases spread by drinking contaminated water. Vector-borne diseases spread by insects like mosquitoes.

Step-by-step solution

1. Typhoid is caused by Salmonella typhi and spreads through contaminated water and food, so it is water-borne. 2. Hepatitis A and E spread through the faecal-oral route via contaminated water, so they are water-borne. 3. Malaria is caused by Plasmodium and spreads by the bite of the female Anopheles mosquito, so it is vector-borne, not water-borne. 4. So only I and II are water-borne. Answer is (A).

Explanation

Typhoid and Hepatitis (A and E) spread when people drink water polluted with faecal matter. Malaria needs water for mosquito breeding, but the disease spreads through mosquito bites, not by drinking water. So it is a vector-borne disease.

Why the other options are wrong

B: Malaria is vector-borne, not water-borne. C: Malaria is vector-borne, not water-borne. D: Hepatitis (A and E) is also water-borne, so 'only I' is incomplete.

Shortcut

Mosquito disease (malaria, dengue) = vector-borne. Faecal-oral disease (typhoid, cholera, hepatitis A/E) = water-borne.

Common mistake

Students mark malaria as water-borne because mosquitoes breed in stagnant water. It is actually water-related (vector-borne), not water-borne.