The aim: The aim of the studies was analysis of methods applied and results of detection and identification of Bacillus anthracis, Yersinia pestis, Francisella tularensis, Brucella sp., Bulkholderia mallei and B. pseudomallei in inactivated samples obtained within the framework of the third external quality assessment exercise (EQAE) in the project ,,Establishment of Quality Assurances for Detection of Highly Pathogenic Bacteria of Potential Bioterrorism Risk (EQADeBa)".
Material and methods: Fifteen samples in the form of water, calf serum and milk spiked with bacteria mentioned above were investigated. Detection and identification of highly pathogenic bacteria were carried out using a PCR technique. RESULTS. Y. pestis, F. tularensis ssp. holarctica, B. anthracis, B. mallei and B. pseudomallei were detected in the investigated samples. The most problematic were samples of milk, probably because of presence of PCR inhibitors such as milk proteins and calcium ions and a low number of bacterial cells contained in the samples. CONCLUSIONS. Inactivation of samples spiked with highly pathogenic microorganisms ensure safety of labora- tory workers, but investigation of such samples needs very precise selection and validation diagnostics methods due to possibility of obtaining false negative results. Results of the third international external quality assessment exercise have confirmed competences of laboratory of Department of Bacteriology NIZP-PZH in the area of detection and identification highly pathogenic bacteria covered by the EQAE.