Never once did i say don't go get them tested I in fact said DO go to a vet and get them tested, the fact of the matter is :
When it is in the same air space it IS NOT a quarantine.
No matter what you do it doesn't stop bacteria and viruses from being transmitted through the air. Unless you change your clothes and shower and make sure you change your shoes(if you wear shoes in your house, I do at my moms she has chipboard flooring right now.. sliver heaven otherwise!

) etc. then you can still get contact transmission.
SO, unless you can provide a separate airspace and are willing to do 2-4 times the amount of laundry per week it's not a true quarantine it's just a cautious introductory phase.
In all reality a "true quarantine" can last for MONTHS depending on what you are looking for because some things may not show up for months. All we do as pet owners is what is in our power, most people don't have a separate facility to house new birds until they are 100% sure they aren't carrying anything. A good example of NO MATTER HOW CAREFUL S%^& STILL HITS THE FAN is the one rescue in Ontario here that works with rats. they do the separate room quarantine(well they did then now i'm not sure they still do or if they cycle them through a foster) BUT anyways, same apartment different room on a completely different side of the apartment. They washed hands, sanitized hands, used different bowls, no animal came into contact with ANY of the "quarantined rats" stuff dishes were done in different sinks and bleach was used to diinfect etc etc.
one rat came in harboring the SENDAI virus (HIGH MORTALITY RATE VIRUS!!)
All normal percautions were followed everyone seemed healthy as per normal everyone was vet checked etc.
no one suspected a thing. then wake up later that week....
WHOLE COLONY INFECTED.
Not just the rats in that room but every rat in the building. the one who came in carrying the virus died and was sent off for a pathology to figure out what was going on etc. Positive test for sendai came back. They lost OVER HALF of the rescues housed there (at that point there was around 45 rats total in the rescue)
considering that there is a HUGE mortality rate with sendai they got lucky, this was one of the first sendai outbreaks in canada.
1 rat with a random disease quarantined the way that everyone here does.
As you can see it is Definitely NOT a true quarantine if it were the healthy animals NEVER would have come into ANY contact with the virus and the number of rats that died would have been greatly minimized.
Sendai is a rare virus in north america it is normally seen in Asia.
SO if I haven't got the point across yet:
IF THE NEW ANIMAL IS INSIDE YOUR HOME IT IS NOT A QUARANTINE.
You can take every per-caution in the world but unless you have a separate airspace if something gets airborne there is nothing you can do to stop it.