Biological weapons are as old as civilization. The latent danger of being attacked with these weapons is still a threat, especially since technological advances, in addition to existing pathogens, can also abuse "new" pathogens with altered properties, created by genetic engineering. Due to their pronounced pathogenicity and ease of spread and resistance to physicochemical influences from the environment, bacteria such as Bacillus anthracis, Yersinia pestis, Francisella tularensis and others have been justifiably classified as potential biological agents by the CDC. Defense against most biological agents, including bacteria, is relatively weak and limited because the stored amounts of vaccines, serums, antibiotics and antidotes against toxins are relatively small, and certainly insufficient for sudden mass outbreaks of the disease. An additional problem is the natural or artificially created resistance of bacteria to antibiotics. One of the most important methods in combating biological agent attacks is to diagnose pathogens as soon as possible in order to take the necessary measures quick and to stop or reduce the spread, morbidity and mortality. A wide range of diagnostic methods and tests, either direct (proving the presence of the causative agent) or indirect (proving antibodies to bacterial antigens), greatly accelerates and facilitates the successful and rapid detection of potential biological agents. The PCR method is, within the direct methods, the method of choice in cases of detection of potential biological agents, because it gives the result quickly and with great precision and accuracy.