A pigeon fancier, had outbreaks of paratyphoid fever in his birds. He lost 15 pigeons with the disease, and he was able to cure only 3 of 30 survivors. He noted other developed a strange phenomenon, they are twisting their heads. Richard wrote and asked if this order of the day.
When birds get sick and you suspect paratyphoid sure you curl on his neck. That is a sure sign that your suffering homing pigeons, in fact, paratyphoid.
Unfortunately, Richard, pigeon paratyphoid can not cure, as they are. Your best defense is to vaccinate your young birds while they are still in the nest. As long as you race your pigeons and birds of other people, you can not prevent your birds from getting the disease. Many people are not conscientious about the vaccination of their children.
You can clear your pigeon and disinfect it regularly, but it will only have limited impact if the people with whom you regularly race does not heal them, and attics.
The biggest problem is once the dove has paratyphoid disease, he will until he dies. You can also tell it to the birds. The disease can remain dormant in birds for some time, but can be transmitted through feces to other birds. There are really only two ways to protect the rest of the pigeons, if it is infected. You can quarantine the infected birds, or you can select it. This may be to make a hard decision, and I do not enjoy, but those are the facts.
There are 28 diseases and parasites, 11 of them suffer from pigeons.