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One article that pertains to young birds may be of interest to pigeon fanciers; Click Here..

POX VACCINATION CONTROVERSY
By David E. Marx, DVM

There continues to be controversy concerning pox vaccination. Some fanciers feel that their birds typically pick up pox from vaccinated birds in their club, etc. Some wish to ban vaccination so that the vaccinated birds do not infect unvaccinated ones. The vaccine virus can cause infection that will spread to other young birds. The longer the scabs last, the longer the virus is available for spread. The virus can live in scab material for some months.

It seems to me that this deprives a fancier of his right to keep his birds disease free. Granted, the vaccinated birds will be contagious for a while. A better choice, in my opinion, is requiring that any vaccination should be done at least two months before the race season; by then they should not still be a threat of contagion. I think that if there is a chance that the birds could contract pox during the race season, a fancier should have the prerogative to protect his birds by vaccinations.

Now, if that area NEVER has natural pox, and sees pox only when someone vaccinates, this is a different story. I wasn't sure that there are areas like that, but have been told that there were. If the birds cannot contract pox naturally then there is no need to vaccinate. It seems, that with birds being shipped here and there, that if a newly acquired young bird, from outside the area, would break with pox, then the they would be in a world of hurt with unvaccinated flocks of youngsters. I also think that everyone should vaccinate in self defense, to be safe.

To me the best answer is to require that no one vaccinates for pox within 2 (or even longer) months before YB race season. Also, it might be good idea to exclude younger young birds, which missed the vaccination, from a vaccinated loft, from being shipped. These birds could keep the virus, of vaccine origin, propagating, and could be a source of infection.

The more you think about it, the more complicated it gets.
I always vaccinated in July for our races which start in September. By then, I believe that there was no trace of virus in my birds; and that they could be commingled with no threat to anyone's unvaccinated birds. If anyone's race birds start popping up with pox during the season, from spending night out and roosting with feral pigeons, then I didn't need to worry about mine contracting it. If there is any work to show that vaccinated birds can carry live virus for more than two months post-vaccination, I do not know about it.

David E. Marx DVM