Chlamydia psittaci Screening of Animal Workers from Argentina Exposed to Carrier Birds

Abstract

Different syndromes are involved in human psittacosis (flu-like syndrome, atypical pneumonia up to lacrimal gland lymphoma). Diagnostic methods include serology, culture, and PCR. The rate of Chlamydia psittaci (Cp) positive tests among exposed workers is still unknown. Our study aimed to assess the rate of positive tests among workers who have contact with carrier birds in natural reserves from Buenos Aires, Argentina. Secondary aims were to analyze risk factors linked to these outcomes and the occurrence of signs that suggest psittacosis. Nasopharyngeal swabs and serum pairs were collected from employees who had interacted with confirmed carrier birds. Those with detectable DNA of Cp and/or anti-Chlamydia spp. antibody baseline titer ≥ 160 mUI/ml, or at least quadruplicating, were considered positive. Activities performed with or near birds, personal protective equipment use, and previous chronic conditions were assessed. Possible Cp-related pathologies were evaluated during follow-up. A total of 63 exposed workers (71.4% men) with a median age of 35.7 years (IQR 26-39) were evaluated to detect 28.6% positives. Respiratory chronic conditions were the unique factor associated with positive tests (OR 5.2 [1.5-18.5] p < .05). Surprisingly, about a third of the workers resulted positive and all responded to medical treatment, none developing an acute atypical pneumonia syndrome associated with classical presentation of psittacosis. Active testing for early diagnosis and proper treatment in zoological workers exposed to carrier or potentially carrier birds is strongly suggested as part of zoonotic diseases preventive measures.

Keywords: Chlamydia psittaci; Carrier birds; Psittacosis; Screening; Veterinary; Workers.