Seropositivity to zoonotic Chlamydophila psittaci in invasive monk parakeets (Myiopsitta monachus) from Santiago, Chile

Abstract

Background: Chlamydophila psittaci is a zoonotic obligate intracellular bacterium that causes the human psittacosis, and its main host are psittacine birds. The monk parakeet is a psittacine bird native to South America, currently being considered an invasive species in 19 countries, including Chile. Aim: To determine positivity to C. psittaci in serum samples and swabs from free-ranging monk parakeets (Myiopsitta monachus) captured in the Metropolitan Region of Chile. Methods: Ninety-five serum samples from nestling chicks and adult monk parakeets were tested using an indirect ELISA test kit. Cloacal and nasotracheal swabs from 40 adult parakeets were further analyzed by C. psittaci-specific real-time PCR. Results: We found antibody titers in sera of five adult monk parakeets (n=68) while none of the nestlings were seropositive (n=27). All samples tested with real-time PCR were negative. Conclusion: Our results demonstrate for the first time in Chile the exposure to Chlamydophila psittaci in free-ranging monk parakeets which may represent a significant risk of pathogen transmission to human and animal populations.