This is a question that most people have a strong opinion about on both sides.
If they are truly only 1-3 day old chicks, and if they came from one of the big hatcheries, there is a very minimal risk of them coming home with a disease. The small risk that exists comes from how long they were sitting at Tractor Supply or your local feed store. People are coming in and out with dirty boots from their farm, etc.. Are they allowed to touch the chicks? Are the chicks locked in a cage where only employees can access (like most Tractor Supply stores do it)? Do they put new chicks in the same bins as the chicks that have been sitting there for the past week? Do they clean anything out regularly (probably not). The risk varies. Did all your chicks come from the same store and therefore most likely have been exposed to the same problems/diseases, simply spread over a few weeks?
My opinion is that the major diseases are not going to show up until they are older. There is no real way to quarantine baby chicks from each other in a manner that would be effective, or for a time span that would be effective in showing a problem in one batch of them. Unless you plan to keep completely separate flocks of birds forever.