Gene sequencing

[Jeffgenetics]

I have a simple question.

Can a virus be sequenced if it hasn't been isolated?

If yes, could you please tell me how it's done?

[CharonY]

Depends on how you define isolated. But if you do not have its DNA in some form, you cannot sequence it. If you got a mi with something x, it is difficult but not necessarily impossible to identify the viral reads from the background. But unless you got a good reference to map the reads to, it would be very tricky indeed. 

[Jeffgenetics]

^{Thanks Charon.}