If you do determine that your rats have SDA, you also need to know that after all of the symptoms have disappeared, they can shed the virus for up to 4 months. That means that a complete quarantine needs to be done for 4 months after the end of all symptoms. No new rats in and no rats leave, along with no litters born. Even though the survivors will act perfectly normal after they finish showing all symptoms, they WILL still be shedding the virus. A complete and thorough quarantine is necessary to contain the virus and stop it from spreading.
Recommended treatment: There is actually no treatment for SDA because it is a virus. However, it is very important that you aggressively treat the secondary infections. You should treat every rat for severe respiratory infections as soon as you know that your colony has been exposed to SDA to prevent as many deaths as possible. A good choice for treatment is a combination of Enrofloxacin (Baytril) and Doxycycline.
This is going to require a contact list be generated for every SARS patient.