Training Manual . — SPb. : Costa, 2009. 224 s. — ISBN 978-5-91258-093-2 (per.) For many years, in monographs, textbooks and articles on microbiology, the authors, directly or indirectly, touched upon the problematic issues of contamination by various microorganisms of any environment and objects, taking into account the possible consequences. Later, the pathogens of hospital (nosocomial) infections, the number of which increases annually, joined to the microbes - contaminants, and the harm from the activity of both groups of microorganisms is extremely high. Therefore, the paper presented to the reader provides basic information about the microorganisms-contaminants and pathogens, taking into account their enzymatic activity in relation to inanimate objects and living beings. Taking into account their main "calling" in nature - the mineralization of various (in form and content) organic substrates including the human body. The book is designed for ecologists, doctors of various profiles and, above all, sanitary and epidemiological services, biologists, builders, microbiologists (mycologists, bacteriologists, antistologists), therapists, etc. as well as students of medical and pharmaceutical academies and universities. The cover shows the synemic growth of Penicillium clavigerum colony, Demelius.