historical introduction

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INTRODUCTION
TO
MEDICAL MICROBIOLOGY
DEEPAK CHAUDHARY
Senior Demonstrator
GMC AMBIKAPUR

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Bacteria
Viruses
Protozoa
Fungi
Algae

5.  Branches of Medical Microbiology
 Bacteriology
 Parasitology
 Mycology
 Virology
 Immunology
 Clinical Microbiology / Infectious Diseases
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History

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 ANTONY VAN LEEUWENHOEK (1632-1723)
 He was the first Person, who invented the
microscope and discovered the microbial world.
 He was a draper (Merchant ) from Delft, Holland.
He used to grind lenses and made microscopes
as a hobby.
 The microscopes of Leeuwenhoek could magnify
objects about 200-300 times.

8.  With his microscopes, Leeuwenhoek observed a
variety of things like rain water, pond water and
scrapings from his own teeth.
 He saw minute moving objects and called them as
“Little animalcules”, which we now know them
as protozoa, yeasts and bacteria.
 He made accurate sketches and communicated his
findings to “Royal Society of London”.
 Thus, Leeuwenhoek was the first person to
discover microscope.
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Augustino Bassi [1835]:
 Muscardine diseases of silk worms was caused by a
fungus.
Oliver Holmes [1840] & Ignaz Semmelweis
[1846]:
 Concluded that puerperal sepsis was transmitted by
contaminated hands of obstetricians, nurses and medical
students.
 This could be prevented by washing hands in antiseptic
solutions.
 Edward Jenner (1749-1823)
 First to prevent small pox.

11.  Father of Microbiology.
 Trained chemist from France
 Established that Fermentation was caused by microbial agents
 Demonstrated anaerobic fermentation by both bacteria and yeasts
(bacteria produce acid and yeast produce alcohol).
 Developed pasteurization to prevent spoilage of wine by bacteria
 Noted that different types of fermentations were associated with
different kinds of microbes.
 Contributed in Development of methods and techniques of
Bacteriology
 Proved that microbes arise only from their like. Disapproved the
theory of spontaneous generation.
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12.  Introduction of sterilization techniques: development of
steam sterilizer, autoclave and hot-air oven
 Studies on Anthrax, Cholera and hydrophobia.
 He coined the term “microbiology”, aerobic, anaerobic.
 He disproved the theory of spontaneous germination.
 Introduced live attenuated (weakened) vaccines.
 [Accidental observation: chicken cholera bacillus
cultures left for several weeks lost their pathogenicity
but retained their ability to protect the chickens from
infection]
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Pure culture of
chicken Cholera
bacteria
8 weeks old
Chicken
inoculated
Remains
Healthy

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Fresh virulent
culture of
chicken Cholera
bacteria Chicken
which is not
previously
inoculated
Chicken
previously
inoculated
Died
Remained
Healthy

15.  Then he attenuated anthrax bacillus by incubation at high
temperatures (42 C-43 C) and proved that inoculation of
such bacilli in animals introduced protection against
anthrax.
 He coined the term ‘Vaccine’ for such prophylactic
preparations.
 While working on rabies, he could not isolate any
microorganism from dog and man but suggested that
causative agent of rabies was too small to be seen by
microscope.
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Louis Pasteur [1822-1895]

16.  Father of Antiseptic surgery
 Professor of surgery
 Applied Pasteur’s work and introduced Antiseptic techniques in
Surgery
 Introduced the Use of Carbolic acid in Antiseptic surgery
 Resulted in drop in morbidity and mortality due to surgical sepsis
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17.  Father of Bacteriology and medical
microbiology.
 Introduced methods for isolation of pure
culture.
 use of solid media for isolation of bacteria
 Introduced Staining techniques
 discovered Anthrax bacillus (1876), Tubercle
bacillus (1882) and cholera vibrios (1883)
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18.  Microorganism can be accepted as the
causative agent of an infectious disease only
if following conditions are fulfilled:
 Disease agent must be present in every organism
suffering from the disease but should be absent in
healthy organism.
 It should be possible to isolate the microorganism in its
pure culture from lesion of the disease
 The isolated microorganism when introduced into
suitable laboratory animal should produce the similar
disease
 It should be possible to re-isolate the microorganism in
its pure culture from lesions produced in experimental
animals.
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20.  Discovery of 1st Antibiotic
 Accidentally discovered Penicillin produced by a fungus
Penicillium.
 Left his Staphylococcus culture on an agar plate for 2
weeks →went on vacation → came back & found mold
on his plate which prevented bacterial growth.
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22.  Father of Chemotherapy
 Applied stains to cells and tissues for study of their
functions.
 Reported the acid-fast nature of tubercle bacillus.
 Discovered Salvarsan (derivative of arsenic) sometimes
called as ‘Magic Bullet’.
 Salvarsan: capable of destroying spirochetes of syphilis.
 Gave rise to new branch of medicine: Chemotherapy’
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23. “To teach is to
learn”
THANK YOU
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“To teach is to learn”