Sick Rooster?

It sounds like Fowl Pox. There is a dry form that last several weeks and is not too serious, but the wet form can get into their mouths, noses, throats, and cause respiratory difficulty and sometimes death. There is very little treatment. Look inside his mouth and throat. He did not catch your cold. He also could have a separate respiratory illness which is coincidental. Here is some infoon diseases: http://edis.ifas.ufl.edu/ps044 Here is a picture of dry fowl pox: https://www.backyardchickens.com/t/690442/is-this-fowl-pox

 

Photos would help, but it sounds like your rooster has Fowl Pox, which is a viral disease characterized by lumps/scabs on the face, comb, and wattles. It also comes in a wet form (the dry form is the one with the external bumps), in which the lumps form inside the mouth and respiratory tract. In severe cases, this can lead to death due to suffocation. I'd look inside your rooster's mouth. If you see any lumps/lesions, then I suspect that the trouble breathing is what is causing him to sneeze. If you don't see any lumps, then he might have a respiratory infection, along with the fowl pox.

There is no treatment for Fowl Pox, but to prevent secondary infection (which your rooster may have--a respiratory infection), treat the bird with an antibiotic. A good choice is Oxytetracycline (sold by names such as Terramycin, Duramycin, Tetroxy HCA-280, etc.). It can usually be found at a livestock supply store, and is generally rather inexpensive, at least as antibiotics go ($9-$15). The dosage is 1/2 teaspoon Oxytetracycline powder per quart of drinking water for 7-14 days. Continue the treatment for the entire amount of time, even if the bird shows improvement after the first few days. Do not give probiotics, Apple Cider Vinegar, or dairy products during antibiotic treatment. Vitamins/electrolytes are fine, though.

I would also, if possible, isolate your rooster. Fowl Pox can often spread through an entire flock, and if he has a respiratory disease, that, too, can spread fast. Keep him in a warm, clean place, and try to minimize external stresses (animals walking around, noise, temperature fluctuations, etc.). Make sure he eats and drinks; encourage him to eat with favorite foods. Drip some water on his beak, or dip it into water to get him to drink. Perhaps put some poultry vitamins/electrolytes in his water to give him an extra boost as well. If he doesn't eat, and you want him to live, you might have to tube feed him. Here is a good link to tube feeding: https://www.backyardchickens.com/t/722041/how-to-t-feed-a-sick-chicken-and-give-subcutaneous-fluid

The Fowl Pox will run its course in 3-6 weeks. Most of the time, unless it is in its wet form, Fowl Pox is not fatal. However, any secondary infections that occur at the same time can be fatal, and that is why treating with antibiotics is recommended.

Hope I've helped! And I hope that your rooster recovers. Just to confirm my diagnosis, it would be great if you posted a photo. Its no use treating something that doesn't exist.

 

As Eggcessive said, it sounds like Fowl Pox. Fowl pox is caused by a virus, and is usually spread by flies, mosquitoes, and other flying insects. Birds that recover are immune, but can be carriers and spread it to other birds. It isn't usually serious, unless it is the wet form, or if a secondary bacterial infections develops because of the stress caused by the disease.

There isn't any treatment, as it is viral. However, to slow the spread of the disease, you might want to treat the area where he lives for flies and mosquitoes. If you have other chickens, isolate him. To prevent secondary infection, treat with a broad-spectrum antibiotic, like oxytetracycline.

The scabs might increase in coverage, and may prevent him from seeing very well. To make him more comfortable, put some petroleum jelly on the scabs. This will soften them, and you'll be able to remove the scabs. Mixing sulphur into the petroleum jelly will help repel insects.

There is a vaccine available for Fowl Pox, so you might want to use it in the future. It is administered into the wing web at twelve weeks of age.

Hope I've helped!