Nowadays increasingly, we hear a lot of pigeon fanciers talk about circovirosis (in Belgium first diagnosed in 1998). Circovirosis is a viral infection of very young pigeons damaging the thymus & bursa Fabricii. These two particular organs are essential for the resistance of our pigeons. By damaging these organs, some infections will occur easier and some vaccinations will not give a full protection anymore (e.g. paramyxovirosis).
New investigations of the pigeon population in Belgium have shown us that a big part of the population is already infected or has been in contact with the circovirus at some time. The known consequences of this infection are mainly secondary infections which can be treated with our regular medicines. But more and more we observe combined infections of circovirus and adenovirus, with all the related consequences.