Guinea hens sneezing.

[Roseheart16]

I have four guinea hens, one about 15 weeks old and the other three a few weeks younger. They started sneezing about four days ago and I figured it was because their pen was dirty so I cleaned it and decided Id wait a few days and if they didn't stop, ask you guys about it. They havent stopped. They started sneezing on a really rainy and humid day so could it be because of that? Is there anything I should do or give them or will it just go away?I house them with three peachicks in similar age but I haven't noticed them sneezing. And I don't see anything except the sneezing wrong with the guineas. Their eyes look clear and they seem to be going about their normal routine.

Is this anything I should be worried about?

Also, yesterday, my oldest guinea's beak started looking kind of flakey. I can get a few pictures of it if that would be helpful.

 

[Roseheart16]

My peachicks are sneezing now as well. I picked one up and checked for a runny nose or other signs of sickness but I didnt notice anything. They are all running about as usual.

I just thought about this the other day when a guinea was having a dirt bath and it was sneezing a lot during that. their pen is outside and one section of it has most of the grass torn out and is all dirt, could they be sneezing from that or from their food being a dusty as well? I try to empty out their food bowl when i fill it and im also considering putting cedar shavings on the ground in that one section and seeing If that helps any.