What the heck is this?! They have swollen eyes and pox - looks like my chickens have chicken pox!

[DanielKYantis]

They are lethargic too! heads down.

 

[Eggcessive]

That is avian or fowl pox--the dry form. It is a virus spread by mosquitoes that usually goes away after 2-3 weeks. The eyes are probably getting infected, so you need to clean them with saline once, and then apply some Terramycin eye ointment or plain Neosporin ointment to their eyes twice a day (on the ones whose eyes have scabs.) If any look weak, or are not eating, look inside their beaks and throat with a flashlight for yellow patches or spots. That is called wet pox, and is very serious. Some sources recommend putting Oxytetracycline in their water with serious cases to help prevent or treat secondary infections such as mycoplasma, even though it has no effect on the pox virus.You may want to separate non-affected chickens if possible, and give them the pox vaccine. Here are some good articles to read:
http://www.thepoultrysite.com/publications/6/diseases-of-poultry/195/fowl-pox/
http://www.the-chicken-chick.com/2015/07/fowl-pox-prevention-treatment.html
http://animalsciencey.ucdavis.edu/avian/Fowlpox.pdf
http://www.hyline.com/aspx/redbook/redbook.aspx?s=5&p=35

 

[kellyhubb]

This page has some good info with photos and references, http://www.poultrydvm.com/condition/fowl-pox-chickens