If you contract the virus then you must self-isolate at home. You can use any paid sick leave you have accrued. You can also seek to use any annual leave or long service leave that you have accrued. Some businesses have also agreed to grant access to special paid sick leave in certain circumstances. You cannot be required to work from home while you are sick.
The Fair Work Commission recently issued a Statement outlining its intention to update 103 awards during the coronavirus pandemic by including an entitlement to unpaid pandemic leave and flexibility to take annual leave at half pay in certain circumstances: