Chlamydial zoonoses

Abstract

Background: Zoonoses were already a subject of intense interest even before the SARS and avian influenza epidemics arose. For many years, chlamydiae have been hypothesized to be important zoonotic pathogens, because of their wide distribution and their infectious cycle. This article provides an overview of the current state of knowledge on this subject.

Methods: The authors present a selective review of the literature as well as their own findings.

Results: The scientific knowledge of the distribution and infectious cycle of chlamydiae is still inadequate. The laboratory diagnosis of chlamydial zoonoses remains unsatisfactory in both human and veterinary medicine, as there are no commercially available sensitive and species-specific tests. Acute chlamydial infections are usually treated with macrolides, tetracyclines, or quinolones. Persistent varieties are not covered by standard therapy.

Conclusions: There is a considerable need for research on chlamydial infections, especially with regard to the diagnosis and treatment of persistent varieties.

Figure 1

a) Smooth muscle cell with inclusion bodies of Chlamydophila (Cp.) pneumoniae (image: Dr. J. Rödel); b) cell culture (BGM), infected with Cp. psittaci, strain DC15, stained with a fluorescently labeled LPS antibody; the chlamydial inclusion appear green (image: Dr. E. Schubert)

Figure 2

Development cycle of Chlamydia; the values given are approximate and may vary between strains; EK, elementary body; RK, reticular body

Figure 3

Chest x-ray of an ornithosis patient (aged 73) with dense infiltration in the left lower lobe and hilus enlargement. Symptoms: flu-like symptoms, dyspnea, dry cough with hemoptysis, fever up to 39°C. In auscultation, fine rales left basal. The pathogen Cp. psittaci was detected in culture and by PCR from BAL (7). PCR, polymerase chain reaction; BAL, bronchoalveolar lavage