Serological evidence of Chlamydia psittaci in psittacines in three zoological parks in Portugal

Chlamydia psittaci is an agent that causes ornithosis or psittacosis, which can infect homing and wild birds, mammalian animals and humans. Since this disease is an important zoonosis that is fatal and distributed worldwide, it is important to know its occurrence. This study aimed to survey the seropositivity of Chlamydia psittaci in three psittacine collections in three zoos in Portugal. In this study, 112 blood samples of the psittacine belonging to Order Psitaciformes (encompassing 31 species from 14 genera) were used. These samples were tested using a commercial ELISA kit (Immunocomb®, Biogal). The serological examination of psittacine samples using ELISA showed that 54 were positive (48.2%; 95% confidence interval, CI: 39.0-57.4%). The genus Ara exhibited significantly higher seropositivity than other genera (P<0.05). Based on the serological data from this study, we demonstrate that antibodies against Chlamydia psittaci are circulating in the blood of these tested animals. Since psittacosis is a public health concern, zoonotic issues of these results should be considered.