Question

Malarial fever is not caused in a person immediately after introducing the sporozoites by an infected anopheles mosquito. Why?

Answer 1

When the Plasmodium is injected into the human from the salivary gland of the mosquito, they migrate to the liver and multiply. They are then transferred to the red blood cells. Blood stage parasite are the ones that cause the symptoms. Hence, we do not see any symptoms immediately when sporozoites infect the humans.