Cocci? Or intestinal shed? 1 week old chick's.

[Hannahnic14]

If they are being vaccinated then you would want to keep them quarantined away from existing flock(s) for a couple of weeks so the Marek's vaccine can "take".
Don't feed medicated feed to chicks that have the Coccidiosis vaccine.

Ok, I didn't know to keep them separated. Thank you!