In vitro detection of neutralising antibodies to Chlamydia suis in pig sera

Chlamydia suis survival in dust: First insights

Chlamydia (C.) suis, a zoonotic intracellular bacterium, is described as a causative agent for conjunctivitis, particularly in nursery and fattening pigs. Chlamydiaceae are claimed to survive drying and to persist in dust. The objective of this study was to evaluate the viability of Chlamydia in dust sampled in a fattening pig farm with a high appearance of chlamydial-induced conjunctivitis. Dust was collected and stored at room temperature. To evaluate bacterial load and survival over time, quantitative PCR (Chlamydiaceae, C. suis) and isolation in cell culture were performed every week for up to 16 weeks. While qPCR results remained highly positive with consistent bacterial loads between 103 and 104 copy numbers/100 μL eluate over a period of 16 weeks and even after 40 weeks, it was not possible to isolate Chlamydia except for the initial sample. These results show only short-term viability of C. suis in dust. This is an important information regarding reduction of chlamydial loads in pig farms and risk for pigs and people to get infected via dust.

Anti-chlamydial IgG Neutralizing Ability in Nonzoonotic Atypical Community Acquired Respiratory Tract Infections

Chlamydophila pneumoniae is a pathogenic agent, involved in various types of infection. This study has evaluated the ability of IgG antibodies in outpatient, with acute respiratory tract infections from C. pneumoniae, to neutralize in vitro purified elementary bodies of this bacterium, revealing a good neutralizing performance of IgG antibodies.