Question

The primary host of the malaria parasite is
A) Male Culex
B) Male Anopheles
C) Female Anopheles
D) Female Culex

Answer 1

Hint : Basically the Malaria protozoa (plasmodium) requires two hosts for the completion of its life cycle. The two hosts are human and mosquitoes.

Complete answer : We know that Malaria is a protozoan disease caused by various species of plasmodium such as plasmodium malaria, Plasmodium vivax and plasmodium falciparum. These are the different species of plasmodium that cause different types of Malaria.

In the following question regarding Malaria we are actually concerned with the life cycle of plasmodium:

The life cycle of plasmodium involves:

The sporozoites enter the human body through the bite of the infected female anopheles’ mosquito (we are quite aware of the hint itself that it is that vector which transmits the disease).
Then, from the blood, they enter our liver cells and multiply within the liver cells. Further, the infected liver cells burst and release the parasites again in the blood.
These plasmodium parasites attack RBC repeatedly to multiply and cause their rupture. The ruptured RBCs releases a toxin known as hemozoin which is responsible for high recurring fever and resultantly, we feel the chills and shivering.
When a female Anopheles mosquito bites an infected person (already infected with malaria), these parasites enter the mosquitoes body and undergo development.
Now as you can see, the role of humans as the host is completed. And, from the entire process that is placed inside the human body it is clear that humans are not the main host of the parasite. Humans here will act as the intermediate host for the parasite.
Now, the parasite is already inside the mosquitoes’ body, here the parasites multiply in the stomach wall of the mosquito and again form sporozoites which are stored in the salivary glands of the mosquito and then again transfer to the human body during the bite of this mosquito.
Process of further development of the parasite is actually taking place inside the mosquito, and from the above discussion, we can conclude that mosquitoes are the main or primary host for the parasite.
The role of mosquito as a vector is also clear from the above process.

Hence the correct answer is option C that is ‘female anopheles’ mosquito.

Note : From the entire process, the role of mosquito as a primary host and human as secondary or the intermediate host is clear. The mosquito here involved is female Anopheles Mosquito that acts as a vector in the entire Malarial infection process (vectors that organism which is involved in the spread of the pathogens).