Transmission of microfilaria in mosquito is -

Ans. is 'a' i.e.s Cyclodeveiopmental o In vector born diseases, an arthropod or any living carrier (e.g., snail) acts as a vector and transports an infectious agent to a susceptible individual, o Transmission by a vector may be of following types : - Mechanical transmission The infectious agent is mechanically transported by the vector, e.g., through soiling of feet of flying arthropod. There is no development or multiplication of infectious agent within the vector. Biological transmission The infectious agent undergoes replication (change in number) or development (change in form) or both in the vector. So, the infectious agent requires an incubation period (extrinsic incubation period) before vector can transmit it to host. This type of transmission is of three types : - Propagative o Agent undergoes multiplication (change in number) in the vector, o There is no development - No change in form, o Example - Plague bacilli in rate fleas. Cyclo-developmental o Agent undergoes only development - Change in form, o No multiplication - No change in number, o Example - Microfilaria in the mosquito. Cyclo-propagative o Agent undergoes both development and multiplication - Change in form and number, o Example - Malaria parasite (Plasmodium sp.) in the mosquito.