Question

Vector for ascariasis is
A. Female Culex
B. Female Anopheles
C. Housefly
D. None of these

Answer 1

Hint: Ascaris lumbricoides also known as roundworms are found in the human intestine, living freely with no organs present for attachment. Their mode of nutrition is holozoic i.e they suck the digested food by the host.

Complete answer:
Mode of transmission if ascariasis is the eggs of the parasite are secreted along with the faeces of an already infected person which further contaminate soil, water and plants. Small children can get infected by ingesting soil. The eggs consumed later hatch in the intestine of the host leading to formation of a juvenile worm which later turns into an adult worm. These eggs can remain alive for several years. The effect of Ascaris infection depends on the degree of infection. It causes weakness and anaemia as the work shares the host food. Toxins released can cause irritation in intestinal mucosa and disturb digestion. Internal bleeding, muscular pain, fever and blockage of intestinal passage are common symptoms which can ultimately lead to consequent death. In children, it leads to poor growth and mental development.

Hence the correct option is option D i.e. none of these.

Additional information:
Certain preventive measures to be taken are disposal of human faeces in an efficient manner, washing vegetables and fruits before eating, protection of food, and washing hands before meal is a very successful preventive device.

Note:
Since it is a helminthic disease, it does not require any type of vector as the causing pathogen is already present in our intestine and this spreads through faecal matter. Adult worms can be treated or removed with the help of certain drugs.