Shippment of viral specimen requires extra precautions that includes:

Specimens for virus detection should reach the laboratory as soon as possible after collection.
Correct handling of specimens during transportation is essential.
Specimens that can be delivered promptly to the laboratory can be stored and shipped at 2-8°C.
When there is likely to be a delay in specimens reaching the laboratory, the use of viral transport medium is strongly recommended.
Specimens may be frozen to - 20°C or ideally -70°C and shipped on dry ice if further delays are expected or transported over long distances.
It is important to avoid repeated freezing and thawing of specimens.