[Zoonoses--a current issue in contemporary infectology].
ABSTRACT INTRODUCTION: Animal infectious diseases which can be transmitted to humans are as old as the civilization itself. It is thought that 75% of all human infectious diseases are of zoonotic origin. Zoonoses are of significant public health importance, with major social and economic impact. GENERAL FACTS ABOUT ZOONOSES: Depending on their life cycle, four groups of zoonoses are distinguished: orthozoonoses, cyclozoonoses, metazoonoses and saprozoonoses. Some zoonoses are of bacterial or viral origin, some are caused by rickettsia or chlamydia, others are mycotic or parasitic infections, whereas some are caused by arthropods or prions. TRANSMISSION OF ZOONOSES TO HUMANS: Three stages are differentiated during the transmission of the causative agent to humans: excretion, presence in the environment and entry into the new host. There are two transmission mechanisms: transmissive (vector-borne) and non-transmissive (fecally-orally). CONCLUSION: Undoubtedly, new zoonoses will continue to emerge, and that is why we need to take seriously the warning of the Third Congress for the European Society for Emerging Infections "to expect the unexpected".