Question

Given below are two statements:
Statement (I): In persistent transmission incubation period is less (from second to minutes).
Statement (II): In non-persistent transmission incubation period is more (from minutes to hours).

• A. Both Statement (I) and Statement (II) are correct
• B. Both Statement (I) and Statement (II) are incorrect
• C. Statement (I) is correct but Statement (II) is incorrect
• D. Statement (I) is incorrect but Statement (II) is correct

Hint:

Non-persistent = Fast in, fast out (seconds). Persistent = Slow in, slow out (hours/days). Think of "Persistence" as a journey through the insect's body.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Virus transmission by insects is categorized by the time the virus stays in the vector and the time required before the vector becomes infectious.
Non-persistent viruses are carried on the mouthparts (stylet-borne).
Persistent viruses circulate within the insect's body (circulative).
Detailed Explanation:
Analysis of Statement (I):
In persistent transmission, the virus must move from the gut, through the hemolymph, to the salivary glands.
This process takes time, known as the "latent period" or incubation period within the vector.
This period usually ranges from several hours to days.
Saying it is "seconds to minutes" is completely incorrect; that describes non-persistent viruses.
Therefore, Statement (I) is incorrect.
Analysis of Statement (II):
In non-persistent transmission, the virus is picked up and delivered almost immediately.
The insect can become infectious within seconds or minutes.
There is essentially no significant incubation period required within the vector.
Saying the period is "more (minutes to hours)" for non-persistent transmission compared to persistent is also backwards.
Therefore, Statement (II) is incorrect.

Step 2: Final Answer:
Both statements are incorrect as they swap the characteristics of persistent and non-persistent transmission times.