Help! Very sick hens and pullets.

[peeps and quacks are me]

Please if you can help, I will take any advice. These are my pets. Some of them have already died. It looks like a cold. Eye drainage, some are closed up and a runny nose/beak. I have given them terramycin in the water, but my problem is spreading.
Help me if you can.
Thank you for your kindness.

 

[MandyH]

Look up Infectious Coryza and see if that fits the description of your birds. You can search it on BYC.

 

[BJ]

Separate the sick ones if possible and dissinfect what you can. Keep them warm and hydrated until you can figure out treatment.

Curious as to how many and what breed.