Prevalence of Coxiella burnetii in environmental samples collected from cattle farms in Eastern and Central Poland (2011–2012)

Coxiella burnetii is the etiologic agent of Q fever. It may occur as two different morphological forms, a large cell variant (LCV) and a small cell variant (SCV). The SCV is characterized by unique resistance to physical and chemical factors and may survive in the environment for many months. The objective of this study was to examine environmental samples for the presence of C. burnetii using real-time PCR in areas where Q fever was previously reported and in randomly selected animal farms where Q fever was not reported. The samples were collected in the following provinces in Poland: Lublin, Subcarpathian and Masovian. Monitoring was performed with real-time PCR and serological methods. Of the 727 environmental samples, 33 (4.54%) contained the multi-copy insertion sequence IS1111, which is specific for C. burnetii. Subsequently, the presence of C. burnetii antibodies was determined using serological tests in selected herds in which positive genetic results were obtained. Serological analyses of 169 serum samples using CFT and ELISA were performed on Polish black-and-white Holstein-Friesian cows and one cow imported from Denmark. Using the CFT method, 11 samples were positive for phase I antibodies and six were positive for phase II antibodies. Moreover, in two cases, the presence of antibodies specific for both phase I and phase II antigens of C. burnetii was detected. However, of the 169 examined serum samples, 20 were positive by ELISA test, of which six were also positive by CFT. Additionally, multi spacer typing (MST) of isolated C. burnetii strains was performed. The MST results identified two new genotypes in Poland, ST3 and ST6. The results indicate that continued research regarding spread of this pathogen within a country is necessary.