İ.Ü. Cerrahpaşa Tıp Fakültesi Mikrobiyoloji ve Klinik Mikrobiyoloji

Anabilim Dalı

Prof Dr Ömer Küçükbasmacı

Introduction to Medical Microbiology

• Severe acute respiratory syndrome coronavirus

• H5N1 avian influenza A virus

• Microbial classification sophisticated

• Anton van Leeuwenhoek 1674

• a world of millions of tiny "animalcules

• Danish biologist Otto Müller

• genera and species according to the classification methods of Carolus Linnaeus

• 1840 the German pathologist Friedrich Henle

Introduction to Medical Microbiology

• Robert Koch and Louis Pasteur

• Anthrax, rabies, plague, cholera, and tuberculosis

• Paul Ehrlich 1910 “salvarsan”

• Alexander Fleming's discovery of penicillin in 1928

Introduction to Medical Microbiology

• Gerhard Domagk's discovery of sulfanilamide in 1935

• Selman Waksman's discovery of streptomycin in 1943

Introduction to Medical Microbiology

• Viruses

• The smallest infectious particles

• Diameter from 18 to nearly 300 nanometers

• Twenty-five families with more than 1550 species of viruses

• More than 40 genera implicated in human disease

Introduction to Medical Microbiology

• either DNA or RNA

• true parasites

• rapid replication and destruction of the cell

• a long-term chronic relationship

Introduction to Medical Microbiology

• Relatively simple

• Prokaryotic

• Cell wall: gram-negative or positive

Introduction to Medical Microbiology

• Fungi

• eukaryotic organisms

• a well-defined nucleus, mitochondria, Golgi bodies, and endoplasmic reticulum

• either in a unicellular form (yeast) that can replicate asexually

• a filamentous form (mold) that can replicate asexually and sexually

Introduction to Medical Microbiology

• Parasites are the most complex microbes • eukaryotic • unicellular and others are multicellular • range in size from tiny protozoa as small

as 1 to 2 μm in diameter (the size of many bacteria) to arthropods and tapeworms that can measure up to 10 meters in length

• Their life cycles are equally complex

Introduction to Medical Microbiology

• Relationship between many organisms and their diseases is not simple

• Treponema pallidum, syphilis; poliovirus, polio; Plasmodium species, malaria

• Staphylococcus aureus-endocarditis, pneumonia, wound infections, food poisoning

• Meningitis caused by viruses, bacteria, fungi, and parasites

Introduction to Medical Microbiology

• Strict pathogens, rabies virus, Bacillus anthracis, Sporothrix schenckii, Plasmodium species

• exogenous infections and examples include diseases caused by influenza virus, Clostridium tetani, Neisseria gonorrhoeae, Coccidioides immitis, and Entamoeba histolytica

Introduction to Medical Microbiology

• person's own microbial flora that spread to inappropriate body sites where disease can ensue (endogenous infections).

• The interaction between an organism and the human host is complex

• The virulence of the organism• The site of exposure• The host's ability to respond to the organism

determine the outcome of this interaction

Introduction to Medical Microbiology

• Quality of the specimen

• The way its sent

• The method used

• The interpretation

Introduction to Medical Microbiology

• Koch's postulates are:• The microorganism must be found in abundance in all

organisms suffering from the disease, but should not be found in healthy animals.

• The microorganism must be isolated from a diseased organism and grown in pure culture

• The cultured microorganism should cause disease when introduced into a healthy organism.

• The microorganism must be reisolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent.