Yersinia pestis (Y. pestis)
Yersinia pestis, the plague bacillus, is often fatal without prompt and appropriate treatment. Plague persistence is partly explained by the fact that it is a zoonotic disease with rodents as reservoirs and fleas as vectors. Yersinia pestis maintains itself among a population of partially resistant rodents and, when transmitted to more susceptible animals, leads to epizootics. Humans can be considered accidental victims when they are bitten by rodent fleas or handle animal tissues or, rarely, inhale airborne bacteria from coughing patients or from infected animals. Late diagnosis is one of the major causes of human death and spread of the disease, since it limits the effectiveness of control measures. In case of natural outbreaks and deliberate or accidental release of these pathogens rapid detection of the bacteria is crucial for limitation of negative effects of the release.