OBJECTIVE This study was aimed at investigating the frequency of infection by Cp. psittaci and determining its genotype in individuals at potential risk of exposure to the bacteria. METHODOLOGY The study involved 170 individuals: a risk group (n= 96) and a low-risk control group (n=74). Cp. psittaci was detected and genotyped by single-tube nested PCR and ompA gene sequencing. RESULTS Eight...

We undertook studies focused on folate acquisition by Chlamydia trachomatis L2, Chlamydia psittaci 6BC, and C. psittaci francis. Results from in situ studies, using wild-type host cells, confirmed that C. trachomatis L2 and C. psittaci 6BC are sensitive to sulfonamides whereas C. psittaci francis is resistant. In addition C. trachomatis L2 and C. psittaci francis were inhibited by methotrexate ...

Addition of murine recombinant gamma interferon (IFN-gamma) to mouse fibroblast cultures infected with Chlamydia psittaci was found to induce a cytotoxic response that was dependent on the concentration of IFN-gamma added and the multiplicity of infection given. No cytotoxicity was observed for uninfected cells treated with IFN-gamma, nor did infection alone elicit cytotoxicity. Cytotoxicity wa...

Chlamydia psittaci is an avian pathogen and zoonotic agent of atypical pneumonia. The most pathogenic C. psittaci strains cluster into the 6BC clade, predicted to have recently emerged globally. Exposure to infected parrots is a risk factor with limited evidence also of an indirect exposure risk. Genome sequencing was performed on six Australian human and a single avian C. psittaci strain isola...

Over the last several years, four different phages of chlamydiae, in addition to a phage associated with Chlamydia psittaci isolated from an ornithosis infection in ducks over 25 years ago, have been described and characterized. While these phages and their chlamydial host specificities have been characterized in vitro, there is virtually nothing known about the interaction of the phage with ch...

Infection with Chlamydiae, specifically Chlamydophila (Cp.) abortus, causes enzootic abortion in small ruminants. The disease is highly prevalent in most parts of the world and has a high economic impact especially on the sheep industry. Swine is another species that can suffer from chlamydial infection. Besides Cp. abortus, Cp. pecorum and Chlamydia (C.) suis can all cause reproductive failure...

Two temperature-sensitive (ts) strains, 1B and 1H, were obtained after nitrosoguanidine treatment of the wild-type virulent abortive ovine strain Chlamydia psittaci AB7. Optimum growth temperature on McCoy cells was 38 degrees C for the three strains, but at the restrictive temperature, 39.5 degrees C, ts strains differed from the parental strain in their total infective yield of chlamydiae, th...

Sarcoidosis and usual interstitial pneumoniae (UIP) are diseases of unknown aetiology affecting the lower respiratory tract. Although there are a number of studies investigating the causal role of these disorders, no micro-organism could be identified as the causal agent. The high incidence of Chlamydophila pneumoniae infections associated with lung injury encouraged the present investigations ...

Chlamydia comprises a group of obligate intracellular bacterial parasites responsible for a variety of diseases in humans and animals, including several zoonoses. Chlamydia trachomatis causes diseases such as trachoma, urogenital infection and lymphogranuloma venereum with severe morbidity. Chlamydia pneumoniae is a common cause of community-acquired respiratory tract infections. Chlamydia psit...

We investigated the acquisition and prevalence of Chlamydophila sp. infection in calves. Specimens were collected at weekly intervals from birth to week 12 postpartum from 40 female Holstein calf-dam pairs in a dairy herd. Real-time PCR detected, quantified, and differentiated Chlamydophila 23S rRNA gene DNA from vaginal cytobrush swabs and milk samples. Chemiluminescence enzyme-linked immunoso...