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PubMed2003

Prevalence of antibodies to Coxiella burnetii among farming population in eastern Poland.

The presence of blood serum antibodies to Coxiella burnetii phase I antigen, indicative of chronic Q fever or convalescence, was found by indirect immuno-fluorescent test in 16 out of 90 examined farmers (17.8 %) living in the Lublin region (eastern Poland) and in none of 30 examined urban blood donors living in the city of Lublin (p < 0.05). In both groups no antibodies to C. burnetii phase II antigen, indicative of acute Q fever, were detected. The frequency of antibodies among farmers was greater in females than in males (26.1 % versus 9.1 %, p < 0.05) and was significantly dependent on age ( xi(2) = 146.42, p < 0.000001) being greatest in the subgroup of farmers aged 41-55 (38.5 %) while no positive reactions were found in young and elderly farmers (respectively, equal to or below 25 and above 56 years). The results suggest that the examined agricultural region could be in the past an epidemic area of Q fever, probably before 15-30 years.

Adolescent↗

PubMed2000

Long-term persistence of Coxiella burnetii in the host after primary Q fever.

After a primary infection Coxiella burnetii may persist covertly in animals and recrudesce at parturition to be shed in the products of conception and the milk. Similar latent persistence and recrudescence occurs in man: namely, infection of placenta, heart valve or mural endocardium, bone or liver. The numbers of organisms, their viability and cellular form, and the underlying organ sites of latent infection for the coxiella are obscure. During investigations of 29 patients with a chronic sequel to acute Q fever, the post-Q fever fatigue syndrome (QFS) [1-3], sensitive conventional and TaqMan-based PCR revealed low levels of C. burnetii DNA in blood mononuclear cells (5/29; 17%), thin needle liver biopsies (2/14; 14%) and, notably, in bone marrow aspirates (13/20; 65%). Irrespective of the ultimate significance of coxiella persistence for QFS, the detection of C. burnetii genomic DNA in bone marrow several years after a primary infection unveils a new pathological dimension for Q fever.

Bone Marrow↗

PubMed1994

Characterization and protective effect of a 29 kDa protein isolated from Coxiella burnetii by detergent Empigen BB.

A 29 kDa protein, isolated from the outer membrane of Coxiella burnetii, strain Nine Mile phase I by detergent Empigen BB, was characterized. The failure in removing lipopolysaccharides (LPS) from preparations of the protein by the purification method used indicates a strong binding between proteins and LPS in the outer membrane of C. burnetii. The protein was immunogenic in mice and protected them against virulent C. burnetii challenge.

Animals↗

PubMed2026

High within-herd prevalence and assessment of production impacts of Coxiella burnetii in postpartum cattle from a Scottish dairy herd.

Coxiella burnetii is endemic in Great Britain dairy herds but detailed investigations of C. burnetii epidemiology and impacts on livestock production in this region are scarce. The objectives of this cross-sectional study were to first determine the within-herd prevalence of C. burnetii on a commercial Scottish dairy farm with prior detection of C. burnetii and second assess the relationship between pathogen load and individual health and performance traits. Vaginal swabs were collected from cows up to seven days postpartum. DNA extracts were tested for C. burnetii by IS1111 qPCR assay. Generalized linear models were used to estimate the relationships between bacterial load and health and performance traits. A total of 313 swabs were collected between 15 December 2022 and 06 July 2023, of which 301 (96.1%) had detectable C. burnetii DNA with Ct ≤ 40. The Ct values observed (12.9-38.7) corresponded to estimated genome equivalents per reaction of < 1 to ∼2.5 million genomes. Higher bacterial loads were seen in primiparous compared to multiparous cows. Higher bacterial loads were also more likely in cows that had experienced one or more negative reproductive outcomes, including abortion, premature delivery, prolonged gestation, stillbirth and dystocia. The direction of causation underlying the observed associations and representativeness of findings from this single herd require further investigation. This study provides insights into the within-herd dynamics of C. burnetii and evidence generated through sampling and diagnostic testing approaches that can inform future work to characterize the epidemiology and impacts of this infection in Great Britain dairy cattle and globally.

Cattle↗

PubMed1999

Coxiella burnetii infection increases transferrin receptors on J774A. 1 cells.

Inoculation with viable, but not inactivated, Coxiella burnetii resulted in the increased expression of transferrin receptors (TfR) in the murine macrophage-like cell line J774A.1. This upregulation was evident in immunoblots as early as 6 h postinfection, with TfR levels continuing to increase through the first 24 h of infection. Fluorescent labeling revealed that TfR upregulation occurred throughout infected monolayers, eliminating the possibility that it reflected a response by a minor subset of host cells. In addition, TfR trafficking did not appear to be affected by C. burnetii infection. Consistent with the increase in TfRs, inoculation with viable C. burnetii resulted in a 2.5-fold increase in total cellular iron by 12 h postinoculation. Our further findings that the chelation of intracellular iron arrests C. burnetii replication and that C. burnetii metabolic activities in vitro are affected by iron concentration suggest that TfR upregulation is a salient factor in C. burnetii infection, and we speculate that it may represent a significant virulence mechanism.

Animals↗

PubMedDate not supplied

Observation on chemotherapy in cows chronically infected with Coxiella burnetii (Q fever).

Pregnant dairy cows chronically infected with Coxiella burnetii were treated orally with 8 mg of chlortetracycline per kilo of body weight each day for 30 days during their dry period. With the exception of a sample of mammary fluid collected at 28 days, rickettsiae were not recovered from the mammary fluids after the second week of treatment. In addition, the organism was not recovered by mouse inoculation from placental tissues, colostrum or calf tissues that were examined after parturition. Results of oral chemotherapy studies in cows and guinea-pigs suggest that in some cases chlortetracycline may suppress rather than eradicate the Q fever agent.

Animals↗

PubMed2006

Analysis of the O-antigen biosynthesis regions of phase II isolates of Coxiella burnetii.

The O-antigen-encoding region in the genomes of 14 isolates of Coxiella burnetii was examined by PCR. Five phase I isolates (Nine Mile clone 7, KAV, Ohio, Henzerling RSA 343, Q173) were analyzed and no deletions were detected. Two other isolates of unknown phase (Scottish, WAV) were examined, but no deletions were detected. In contrast, RSA 514 and three phase II isolates (Nine Mile phase II clone 4, Nine Mile phase II clone 1, Nine Mile Baca) contained large deletions, and the latter two were further characterized by DNA sequencing. Three other phase II isolates (Henzerling RSA 331, M44, Australian QD) contained no apparent deletions. Reactivity to phase I- and phase II-specific antibodies by immunofluorescence assay was used to further characterize isolates. Selected ORFs in Australian QD and M44 DNA were sequenced to detect mutations, and no significant changes were found. Australian QD RNA was examined by reverse transcriptase-PCR specific to the four ORFs hypothesized to encode the O-antigen sugar virenose, which this isolate has been shown to lack, as well as one that is predicted to encode part of the O-antigen ABC transporter. Each of these five genes was found to be expressed.

Antibodies, Bacterial↗

PubMed1998

Clinical evaluation of a new PCR assay for detection of Coxiella burnetii in human serum samples.

A nested PCR method was developed for the detection of Coxiella burnetii in human serum samples. Two pairs of oligonucleotide primers were designed to amplify a 438-bp fragment of the com1 gene encoding a 27-kDa outer membrane protein of C. burnetii. The primers amplified the predicted fragments of 21 various strains of C. burnetii but did not react with DNA samples from other microorganisms. The 438-bp amplification products could be digested with restriction enzymes SspI and SalI. The utility of the nested PCR was evaluated by testing human serum samples. The com1 gene fragment was amplified from 135 (87%) of 155 indirect immunofluorescence test (IF)-positive serum samples and from 11 (11%) of 100 IF-negative serum samples. The nested PCR with primers targeted to the com1 gene appeared to be a sensitive, specific, and useful method for the detection of C. burnetii in serum samples.

Antibodies, Bacterial↗

PubMed1998

Evaluation of a recombinant 27-kDa outer membrane protein of Coxiella burnetii as an immunodiagnostic reagent.

The 27-kDa outer membrane protein from eight strains of Coxiella burnetii was expressed in the pET-21c protein expression system. Two fusion proteins with molecular masses of 30 and 32 kDa were evident in all eight of the recombinants by SDS-PAGE and immunoblotting. A protein having an approximate size of 30 kDa was purified from the Escherichia coli lysates by one-step affinity purification. The utility of the purified recombinant protein in ELISA was also evaluated by testing its reactivity with human sera and comparing this reactivity with that of Nine Mile phase II antigen. All of the 40 IF-positive serum samples were ELISA-positive for both the Nine Mile phase II and recombinant antigens, and negative serum controls were negative for both antigens. These results suggest that ELISA with the 27-kDa recombinant antigen is a sensitive and specific method for detecting anti-C. burnetii antibodies in human sera.

Animals↗

PubMed2005

Prevalence of antibodies to Coxiella burnetii among veterinary school dairy herds in the United States, 2003.

Prevalence of antibodies to Coxiella burnetii in 24 veterinary school-associated dairy herds in the United States was assessed through laboratory testing of bulk tank milk specimens by indirect immunofluorescent antibody assay. Twenty-two herds (92%) had evidence of antibodies to C. burnetii Phase I antibodies at a titer of > or = 1:16, and nine herds (38%) had Phase I antibody titers of > or = 1:256. These results suggest that C. burnetii infection is geographically widespread among dairy herds in the United States.

Animals↗

PubMed1989

Different priming on human neutrophil respiratory burst by lipopolysaccharides from phase I and phase II Coxiella burnetii.

Human neutrophils produce small amounts of superoxide anion when stimulated with the chemotactic peptide FMLP; preincubating neutrophils with low concentrations of lipopolysaccharides (LPS) markedly increases this response, an effect referred to as priming. In this work LPS from Coxiella burnetii either phase I (virulent) or phase II (avirulent) were examined for their ability to induce priming. Results clearly show that only LPS from phase II microorganism was able to increase the release from neutrophils upon subsequent stimulation with FMLP. This effect was abolished by preincubation of LPS with polymyxin B. This finding may account for the ability of Coxiella burnetii phase I to escape intracellular phagocyte killing during persistent infections.

Coxiella↗

PubMed1995

Coxiella burnetii (Q fever) pneumonia.

Pneumonia is one manifestation of acute Q fever following infection with Coxiella burnetii. Fever, headache, and myalgia dominate the clinical picture of Q fever pneumonia. Cough is nonproductive and may be absent despite the presence of pneumonia. While in most instances pneumonia results in an illness of mild-to-moderate severity, on occasion it is rapidly progressive and results in respiratory failure. Infection occurs as a result of inhalation of contaminated aerosols. Infected cattle, sheep, and goats are the usual reservoirs for this zoonosis. In some areas, infected parturient cats serve as the reservoir, and in such instances, rounded opacities are seen on the chest radiograph. The diagnosis of C. burnetii pneumonia is usually confirmed by demonstration of a fourfold or greater rise in antibody titer. Treatment is usually with a tetracycline or rifampin for 7 to 10 days.

Adult↗

PubMed2006

[Development of effective detection method for Coxiella burnetii in mayonnaise by real-time PCR and investigation of C. burnetii contamination in commercial mayonnaise in Tokyo].

A PCR method for the effective detection of Coxiella burnetii in commercially available mayonnaise was developed. Sample preparations were isolated from 50 g portions of each mayonnaise product by four successive extraction steps in phosphate buffer with 2.0 M NaCl. These extracts were then centrifuged at 20,000 x g for 60 min. DNA was isolated from the solution containing the precipitate with a commercial kit, and amplified quantitatively using real-time PCR that targeted the com1 region of C. burnetii. The recoveries of C. burnetii from 2 kinds of commercial mayonnaise specimens, with a baseline control of 1 x 10(7) particles of the Nine Mile phase II strain, were 85.0 +/- 6.0% and 72.0 +/- 0.4%, respectively. The determination limit of this method was 500 C. burnetii particles per 50 g of mayonnaise. The DNA specimens isolated from 50 different commercial mayonnaise samples sold in Tokyo using this method were amplified using both nested PCR and real-time PCR. No contamination by C. burnetii was detected in any of the mayonnaise samples.

Coxiella burnetii↗

PubMed1996

[Ticks as a reservoir of Borrelia burgdorferi and Coxiella burnetii on Polish terrain].

The aim of performed studies was to recognize the distribution of Coxiella burnetii and Borrelia burgdorferi infected ticks in Poland. The 1580 ticks infesting animals and humans were collected in different parts of the country. They belonged to Ixodes ricinus, Dermacentor reticulatus and Argas reflexus species. Presence of B burgdorferi and C. burnetii DNA in ticks has been sought with polymerase chain reaction test (PCR). B. burgdorferi bacteria have been detected in 12 I. ricinus ticks (0.77%). Infected ticks were collected in Koszalin, Krosno and Suwałki voivodships. C. burnetii bacteria were found in 3 ticks from Kielce and Tarnobrzeg voivodships (0.19%). Obtained results indicate existence of natural reservoirs and vectors of C burnetii and B. burgdorferi in Poland. Since Q fever have not been recognized in central Poland until recently in can suggest diffusion of the C. burnetii reservoir to new regions. Presence of infected ticks in distant regions reflects wide distribution of these microorganisms all over the country.

Animals↗

PubMed2002

Phase variation analysis of Coxiella burnetii during serial passage in cell culture by use of monoclonal antibodies.

Antigenic changes in Coxiella burnetii Nine Mile strain phase I during serial passages in cell culture were analyzed with three groups of monoclonal antibodies (MAbs) against lipopolysaccharide. The MAbs of group 1 did not react with organisms that were passaged over five times, and the MAbs of group 2 did not react with organisms that were passaged over eight times. The MAbs of group 3 reacted with organisms passaged up to 15 times but did not react with phase II cells. These results suggest that C. burnetii could be differentiated into four phase states during phase variation.

Animals↗

PubMed1993

Cloning and sequencing of Coxiella burnetii outer membrane protein gene com1.

The gene for an approximately 27-kDa outer membrane-associated, immunoreactive protein was cloned from the rickettsial pathogen Coxiella burnetii. The gene, designated com1 for Coxiella outer membrane protein 1, was expressed in Escherichia coli, presumably by its own promoter. The complete nucleotide sequence of the gene was determined. The deduced amino acid sequence of 252 residues includes a putative leader sequence. The leader sequence is recognized in and removed by E. coli on the basis of the difference in the molecular mass of the protein produced in an in vitro transcription-translation system (27.6 kDa) and that of the protein immunoprecipitated from an iodinated E. coli clone (25.7 kDa). The Com1 protein expressed in E. coli was proteinase K sensitive in nondisrupted cells and soluble in 1% Sarkosyl, suggesting a loose association with the outer membrane. While the complete predicted sequence of the Com1 protein does not show any overall similarity to those of previously described proteins, a region which includes the only two cysteines in Com1 is homologous to the catalytic site of protein disulfide oxidoreductases.

Amino Acid Sequence↗

PubMed2005

Coxiella burnetii in bulk tank milk samples, United States.

Dairy cattle are a primary reservoir of Coxiella burnetii, which causes Q fever. However, no recent nationwide studies have assessed the prevalence and risks of Q fever in dairy cattle. We report >or=94% prevalence in samples of bulk tank milk from U.S. dairy herds tested during the past 3 years.

Animals↗

PubMed1993

[Abortions in a lower Austrian sheep facility caused by Coxiella burnetii].

In a flock of sheep the causal connection between abortions and the infection with Coxiella burnetii is demonstrated serologically, bacteriologically and by pathological examination. In order to identify C. burnetii as causing agent in case of abortions the submission of placental parts in addition to the fetus, in combination with a serological control of the flock, is recommended. To check the seroprevalence of C. burnetii in the region concerned random blood samples of 12 flocks were taken and analysed by CFT. At least 10 samples per herd, taken from animals more than 1 year old, were examined. Positive titers were found in 5.6% of the checked animals which originated from 6 different flocks. Health risks of different groups of the human population are being discussed.

Abortion, Veterinary↗