INTRODUCTION
TO
MEDICAL MICROBIOLOGY
Mr. Norazli Ghadin
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Dr.T.V.Rao MD
Course Outline
• Subject Name : Medical Microbiology 1
• Subject Code : MLT 1222
• Contact Hour/Week :
– Theory & tutorial 2 hour
– Lab 2 hour
• Assessment :
–
–
–
–
Final examination : 60 %
Mid term : 20%
Quiz : 5%
Attendance & Participitation : 5 %
Learning Objective
 Know the History of medical microbiology
 Understands the field of microbiology
 Explain the importance of medical
microbiology
 Explain laboratory safety
 List essential topics in medical microbiology
 Know and understand the laboratory
procedure involved in microbiology
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Topics
No
Topic
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Introduction to Medical Microbiology
2
Laboratory Rules and Hazards Symbols
3
Sterilization Technique
4
Microbiology Instrumentation
5
Introduction to bacteriology
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Bacterial culture and growth
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Technique in bacteriology lab
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Culture media
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Bacterial Staining and microscopy
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Bacterial Count
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Biochemical Test
MID
Term
Final
Lets the
fun Start
Course objectives
 To provide the student with the basic
knowledge of micro-organisms in
general
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Dr.T.V.Rao MD
Coverage of subject
General
Microbiology
Bacteriology
Mycology
Virology
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What is Microbiology?
Microbes, or microorganisms are minute living
things that are usually unable to be viewed with the
naked eye.
What are some examples of microbes?
Bacteria, fungi, protozoa, algae, viruses are
examples!
Some are pathogenic
Many are beneficial
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Dr.T.V.Rao MD
Defining Microbiology
• Microbiology :
The study of organisms too small to be seen
with the naked eye
• Eg:
• viruses,
• bacteria,
• algae,
• fungi,
• Protozoa
Dr.T.V.Rao MD
• Microbiologists
study the
– morphology
– cytology,
– physiology,
– ecology,
– taxonomy,
– genetics,
– molecular biology
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Organisms included in the study of
Microbiology
Organism
Name of study
1.
Bacteriology
Protozoology
Phycology
Parasitology
Mycology
Virology
Bacteria
2. Protozoans
3. Algae
4. Parasites
5. Yeasts and Molds
Fungi
6. Viruses
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History of Microbiology
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1673-1723, Antoni
van Leeuwenhoek
(Dutch) described
live
microorganisms
that he observed in
teeth scrapings,
rain water, and
peppercorn
infusions. Dr.T.V.Rao MD
Anton van Leeuwenhoek 1674
- 1st person to actually see living microorganisms
荷兰人吕文虎克
（Leeuwenhoek）1632-1723
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“wee animalcules”
Dr.T.V.Rao MD
History of microbiology
 Anton van Leeuwenhoek (1632–1723): was the first
microbiologist and the first person to observe bacteria using a
single-lens microscope of his own design.
 Louis Pasteur (1822–1895): Pasteur developed a process
(today known as pasteurization) to kill microbes.
pasteurization is accomplished by heating liquids to 63° to
65°C for 30 minutes or to 73° to 75°C for 15 seconds.
 Robert Koch (1843–1910): was a pioneer in medical
microbiology and worked in cholera, anthrax and
tuberculosis. He was awarded a Nobel prize in 1905 (Koch's
postulates) he set out criteria to test.
 Alexander Fleming (1929): Discovered penicillin.
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Dr.T.V.Rao MD
Louis Pasteur
1922 - 95
 Contributed best in






Microbiology
Sterilization
Hot Air oven
Autoclave
Anthrax vaccine
Rabies vaccine
Built the Pasteur Institute
Dr.T.V.Rao MD
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Louis Pasteur
 Pasteur coined the
word Vaccine
 Vacca – Cow cow pox
virus are given for the
prevention of Small Pox
 Louis Pasteur
considered the father of
Modern Microbiology
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Dr.T.V.Rao MD
Robert Koch
1843 - 1910
 A German scientist
 Formulated the
Bacteriological techniques
 Staining Methods
 Discovered the
Mycobacterium and
Vibrio cholera
 Introduce systematic
methods to prove causes of
diesease. (Koch postulate)
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Koch’s Postulates
1 The bacterium should be constantly associated with lesions of
Disease
2 It should be possible to isolate the bacterium in pure culture
from the lesions
3 Inoculation of such pure culture into laboratory animal should
reproduce the lesions of the disease
4 It is possible to reisolate the bacterium in pure culture from the
lesions produced in the experimental animal
Additional criterion specific antibodies in the serum of
patients suffering with disease
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Dr.T.V.Rao MD
Koch’s postulates
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Dr.T.V.Rao MD
Microbes make the Universe
 There are > 5 x 1030
types Microbes in the
world
 Humans have intimate
relation with Microbes
> 90% of the cells in
our Body are Microbes
Dr.T.V.Rao MD
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Classification Taxonomy of
Microorganisms
 Three domains
 Bacteria
 Archaea
 Eukarya
 Protists
 Fungi
 Plants
 Animals
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Taxonomy
Kingdom
Animalia
Animalia
Phylum
Chordata
Chordata
Class
Mammalia
Mammalia
Order
Carnivora
Primata
Family
Canidae
Hominidae
Genus
Canis
Homo
Species
familiaris
sapiens
Naming and Classifying
Microorganisms
 Carolus Linnaeus (1735)
established the system of
scientific nomenclature.
 Each organism has two
names: the genus and specific
epithet.
 Are italicized or underlined.
The genus is capitalized and
the specific epithet is lower
case.
 Eg: Homo sapiens
Homo sapiens
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Dr.T.V.Rao MD
How to Study Medical Microbiology?
Fundamentals of Microbiology
Bacteriology
Virology
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Mycology
Dr.T.V.Rao MD
•Biological Properties
•Morphology, identification,
•Pathogenesis and Pathology
•Clinical findings
•Diagnostic Laboratory Tests
•Treatment & Prevention
•Epidemiology & Control
Basic Classification of Microorganism
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 Eukaryotes
Prokaryotes
Large in size
Mitochondria Present
Membrane bound Nucleus
Eg Algae
Protozoa
Fungi
Slime Moulds
Contains all enzymes for
production of metabolic
energy
Small in Size
DNA not separated from
cytoplasm
Mitochondria absent
Dr.T.V.Rao MD
Eg Bacteria
Contains all enzymes like
Eukaryotes
Summary of differences between
prokaryote and eukaryote cells
Prokaryotic cells
Eukaryote cells
Small cell (< 5µm)
Larger cells (> 10 µm)
Always unicellular
Often multicellular
No nucleus or any membrane bound organelles
Always have nucleus and membranes bound
organelles.
DNA circular, without proteins
DNA is linear and associated with proteins to
form chromatin.
Ribosomes are small 70S
Ribosomes are large 80S
No cytoskeleton
Always have cytoskeleton
Motility by rigid rotating flagellum made from
flagellin
Motility by flexible waving cilia or flagella
made from tubulins.
Cell division is by binary fission
Cell division is by meiosis and mitosis.
Reproduction is always asexual
Reproduction is sexual and asexual.
Bacteria
 Prokaryotes
 Peptidoglycan cell
walls
 Binary fission
 For energy, use
organic chemicals,
inorganic chemicals,
or photosynthesis
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Dr.T.V.Rao MD
Pathogenic Prokaryotes
Bacteria
Mycoplasma
Spirochetes
Chlamydiae
Rickettsia
Actinomyces
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Dr.T.V.Rao MD
Viruses
A viral particle consists of a nucleic acid molecule, either DNA or RNA,
enclosed in a protein coat, or capsid
Viruses lack many of the attributes of cells, including the ability to replicate.
Only when it infects a cell does a virus acquire the key attribute of a living
system: reproduction
Viruses are known to infect all cells, including microbial cells. Host-virus
interactions tend to be highly specific
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Dr.T.V.Rao MD
Discovery of Virus
 Iwanovski
 a Russian chemist, 1892
 Tobacco Mosaic Disease
 Beijerinck confirmed
 Walter Reed, USA
 Yellow fever virus
 Ist human virus
Tobacco mosaic disease,
caused by the tobacco
mosaic virus
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Dr.T.V.Rao MD
Prion
A kind of infectious protein that can resist the digestion of proteinase
The cellular form of the prion protein (PrPc) is encoded by the host’s
chromosomal DNA
An abnormal isoform of this protein (PrPres) is the only known component of
the prion and is associated with transmissibility.
Kuru, Creutzfeldt-Jakob disease (CJD), GerstmannSträussler-Scheinker disease, fatal familial insomnia
, and Bovine spongiform encephalopathy (BSE)
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Dr.T.V.Rao MD
Viroid
Small, single-stranded, covalently closed circular RNA molecules existing as
highly base-paired
rod-like structures; they do not possess capsids
They range in size from 246 to 375 nucleotides in length. The extracellular form
of the viroid is naked RNA—there is no capsid of any kind
The RNA molecule contains no protein-encoding genes, and the viroid is
therefore totally dependent on host functions for its replication
The RNAs of viroids have been shown to contain
inverted repeated base sequences at their 3' and 5' ends, a characteristic of
transposable elements and retroviruses. Thus, it is likely that they have evolved
from transposable elements or retroviruses by the deletion of internal sequences
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Dr.T.V.Rao MD
Scientific era of Antibiotics
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1928: Alexander
Fleming discovered
the first antibiotic.
He observed that
Penicillium fungus
made an antibiotic,
penicillin, that killed
S. aureus.
1940s: Penicillin was
tested clinically and
mass produced.
Dr.T.V.Rao MD
Discovery of Antibiotics
 Alexander Fleming (1881-1955)
Sir Alexander Fleming
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Dr.T.V.Rao MD
Ernst Boris Chain
Sir Howard Walter Florey
Microbes are used to produce
Antibiotics
 Penicillin
 Mold
 Pencillium notatum
 1928 Alexander Fleming
Dr.T.V.Rao MD
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Modern Developments
• Bacteriology is the study of bacteria.
• Mycology is the study of fungi.
• Parasitology is the study of protozoa and
parasitic worms.
• Recent advances in genomics, the study of
an organism’s genes, have provided new
tools for classifying microorganisms.
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Dr.T.V.Rao MD
Microbes and Human Disease
• Normal micro biota prevent growth of
pathogens.
• Normal micro biota produce growth factors
such as folic acid and vitamin K.
• Resistance is the ability of the body to
ward off disease.
• Resistance factors include skin, stomach
acid, and antimicrobial chemicals.
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Dr.T.V.Rao MD
Bacteria - what comes to mind?
 Diseases
 Infections
 Epidemics
 Food Spoilage
 Only 1% of all known bacteria cause human diseases
 About 4% of all known bacteria cause plant diseases
 95% of known bacteria are non-pathogens
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Dr.T.V.Rao MD
 Staphylococcus aureus
 Escherichia coli
 Staphylococcus epidermidis
 Bacillus anthrasis
 Streptococcus pneumonia
 Salmonella enteridis
 Streptococcus pyogenes
 Vibrio cholera
 Steptococcus lactis
 Rhodospirillium rubrum
 Streptococcus faecalis
 Bacillus subtilis
 Erlichia canis
 Campylobacter jujuni
 Micrococcus luteus
 Helicobacter pylori
 Enterobacter aerogenes
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Dr.T.V.Rao MD
Microbes Benefit Humans
1.Bacteria are primary decomposers - recycle nutrients back
into the environment (sewage treatment plants)
2. Microbes produce various food products
 cheese, pickles, sauerkraut, green olives
 yogurt, soy sauce, vinegar, bread
 Beer, Wine, Alcohol
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Dr.T.V.Rao MD
Microbes are also capable of
causing many diseases
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Pneumonia
Whooping Cough
Botulism
Typhoid Fever
Measles
Cholera
Scarlet Fever Mumps
Syphilis
Gonorrhea
Herpes 1
Chlamydia
Tuberculosis Herpes 2
Meningitis
Tetanus
RMSV
Strep Throat
Lyme Disease AIDS
Black
Plague
Diarrhea
Gangrene
Dr.T.V.Rao
MD
Parasitology
 Parasitology is the study of
parasites .and their
interactions with their
hosts. The science of
parasitology has a long
history and has its roots in
zoology, with its emphasis
on the identification and
classification of parasites
and of life cycles,
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Dr.T.V.Rao MD
What Are Fungi
 Considerable variation in
size.
 Internal Molecular system
 Well defined cell wall
composed of
polysaccharides
 Gaining importance in
Immunosupressed patients
and increased use of
Antibiotics
Dr.T.V.Rao MD
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Zoonotic Diseases
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Dr.T.V.Rao MD
How Humans Respond to Infections
Study of Immunology
 In spite of Infection we
survive with our ability to
protect with a system
inherent in our Body
 Called the Immune response
comprises the Medical
Immunology
Dr.T.V.Rao MD
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Why we should
Medical Microbiology
 We study the Microbes which
infects and causes Diseases
 We study their
Diagnosis
Prevention
Treatment
Dr.T.V.Rao MD
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Modern Developments in
Microbiology
 Immunology is the study of
immunity. Vaccines and
interferons are being
investigated to prevent and
cure viral diseases.
 The use of immunology to
identify some bacteria
according to serotypes
(variants within a species)
was proposed by Rebecca
Lancefield in 1933.
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Dr.T.V.Rao MD
Must learn
 Natural History of the Disease
 Etiology
 Pathogenesis
 Laboratory Diagnosis
Treatment and Control and
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Prevention
Dr.T.V.Rao MD
We must be familiar with
Knowledge On ….
 Names of the Microbes
 Names of the diseases
 Mode of transmission
 Pathogenic Microbes
 Commensal Organisms
 Identify wether Bacteria, Virus, Parasite or Fungi
 Treating and Preventing
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Dr.T.V.Rao MD
The Birth of Modern Chemotherapy
 Treatment with chemicals is chemotherapy.
 Chemotherapeutic agents used to treat infectious disease can be
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synthetic drugs or antibiotics.
Antibiotics are chemicals produced by bacteria and fungi that
inhibit or kill other microbes.
Quinine from tree bark was long used to treat malaria.
1910: Paul Ehrlich developed a synthetic arsenic drug,
salvarsan, to treat syphilis.
1930s: Sulfonamides were synthesized.
Dr.T.V.Rao MD
Commonly Used Antibiotics
 Penicillin
 Cephalosporins,
 Tetracycline's
 Quinolones
 Vancomycin
 Chloramphenicol
 Drugs for Tuberculosis eg Streptomycin
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Dr.T.V.Rao MD
Vaccines Produce Immunity
and Prevents Several Infections
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Dr.T.V.Rao MD
Commonly used Vaccines
 Small pox eradicated
 BCG,
 MMR
 Polio oral Vaccine
 Triple Antigen
 Hepatitis B Vaccine
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Dr.T.V.Rao MD
What Skills You should
Develop
Able to identify the Infective Conditions
Timely Diagnosis
Choosing appropriate tests
Selection of Antibiotics
Implement measures to prevent diseases in
patients and Society
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Dr.T.V.Rao MD
Protect Yourself from
Infections
 Certain infections
can infect you
 Eg HIV, Hepatitis B
infections,Tubercul
osis,Many
respiratory
infections
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Dr.T.V.Rao MD
Working In the Hospital
 Hospitals are not safe
 Follow Universal
precaution protect yourself
as our patients can be
source of Infection if you
don't handle the matters
with scientific knowledge.
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Dr.T.V.Rao MD
Medical Microbiology advanced Beyond our
Imagination
Can we handle it ???
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Dr.T.V.Rao MD
Email
Norazli.ghadin@city.edu.my
Web
Norazlicucst.weebly.com
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Dr.T.V.Rao MD