Question

differentiate between the different modes of viral transmission by insects

Answer 1

Different modes of viral transmission include:

non-persistent

semi-persistent

persistent

Non-persistent	Semi-persistent	Persistent
They are retained in the insect stylet	They are internalised in the insect by binding into chitin lining in the gut but do not appear to enter tissues.	They are taken up into and retained by insect tissues and are characterised by invading salivary glands.
Retained by vectors for a short period usually a few hours or less.	Retained by vectors for long period often weeks or months.	Retained by vectors for an intermediate period