Question

how mosquitoes can spread a disease from an infected person to healthy person?

Answer 1

Organisms which do not cause diseases themselves, but spread infection by transferring disease-causing microorganisms from an infected person to others are known as vectors. Mosquitoes acts as vectors.

Female mosquitoes require highly nutritious blood to lay eggs, so they feed on warm-blooded animals like humans. The female mosquito that bites an infected person can transfer the disease-causing microorganism from an infected person’s blood to a healthy person, on biting the healthy person afterwards. Hence, spread disease.