Question on kilobase - packaging of genomic material in viruses
This value is only true for linear DNA. However, DNA in cells is not linear, it is folded, which makes it ways more compact (otherwise the DNA in our own cells would be around 2 meters long).

See the figure from reference 1 for a schematic view how this works in higher cells:



The table below (from reference 2, either klick on the picture or the link below for a bigger version) shows how the length of a piece of DNA is influenced by packaging:



There is another caveat in this question, Corona viruses (as the SARS virus) are singlestranded RNA viruses. The RNA of viruses contains packaging signal sequences, where special proteins bind, before the virus is assembled around the bound genetic information. See reference 3 for a general overview and reference 4 for the packaging of the SARS virus in special.


DNA Packaging: Nucleosomes and Chromatin
DNA, chromatin and genome numbers
Genome packaging in viruses.
Assembly of severe acute respiratory syndrome coronavirus RNA
packaging signal into virus-like particles is nucleocapsid
dependent.