Microbiology Unit 1: Introduction

Microbiology and Parasitology

UNIT 1: INTRODUCTION

Some rules

• Listen when others are talking

• Show respect for other opinions

• If you don’t understand, don’t hesitate to ask (raise hand)

• No cellphones in the class room

• Full participation is asked

Microbiology

Virus: Ebola

Fungi: MushroomBacteria: Salmonella

?ENEMY OR… …FRIEND

Algae: Algal bloom

MICROBES

Course content

• Theory– Burton’s Microbiology for the Health Sciences – P.G. Engelkirk & J. Duben– Microbiology and Infection – T.J.J. Inglis

• Practice: demonstrations in laboratory science– Growth of bacteria– Growth of fungi

• Tests• Assignments• Final examination

Website

• http://pson-biochemphys.yurls.net/en/page/

Today

• Microbes– Definition– Presence– Variety– Enemy or friend?

• Historical Background– Earliest known diseases– Fouding fathers

• Microbiology in health care– Possible careers

Definition?

• MICRO – BIO – LOGY

– μικρος = micros = “small”– βιος = bios = “life”– λογος = logos = “science”– “The study of very small living organisms”

• or: MICROBIOLOGY

– “The study of microorganisms (microbes) usually less then 1 mm in diameter which requires some sort of magnification to be seen clearly”

Burton’s Microbiology: Chapter 1

Presence of Microbes

• Microbes are ubiquitous: virtually everywhere– Water (photosynthetic algae, plankton)– Dead or decaying materials (decomposers/saprophytes)– Soil (bacteria used in microbial ecology)– Animals/plants (bacteria and protozoa in intestinal tract)– Food/drinks (yeast in bread and beer)– Laboratory (study or to produce antibiotics, insulin, hormones)


MANY MICROBES

ARE USEFUL

(FRIENDLY)

Variety of Microbes

• Categories– Acellar: Viroids, Virus, Prion– Prokaryotes (cellular without nucleus): Bacteria, Archaea, Cyanobacteria– Eukaryotes (cellular with nucleus): Algae, Fungi, Protozoa


Microbes

Acellular ViroidsPrions

Virusus

Cellular

ProkaryotesArchaeaBacteria

Cyanobacteria

EukaryotesAlgaeFungi

Protozoa

Microflora

Indigenous microflora

(100 trillion)

Nonpathogens (97%)

Opportunistic pathogens

Pathogens / infectious

agents (3%)

FRIENDSMICROBIAL ALLIES

ENEMIESMICROBIAL ENEMIES

“GERMS”

USED-TO-BE-FRIENDSPOTENTIAL ENEMIES


• All microbes living on our bodies: Indigenous Microflora

Disease

Health Care!

• Microbial enemies…– …cause disease– “Pathogens”– Two categories

• Infectious diseases– 50.000 deaths/day– Majority in

developing countries

• Be aware of…– Infectious diseases– Pathogens– Source– Transmission– Protection/prevention


Earliest known diseases

3180 BC

1900 BC

1500 BC

1122 BC

790-640 BC

430 BC 1493

0 2015

Egypt: First recorded pestilence

Troy: Bubonic plague

Egypt: Epidemic fevers

China: Smallpox

Rome: Epidemics of plague

Greece: Epidemics of plague

Europe: Syphilis


Historical background

• Once upon a time…


… they had no idea

Until…

Antoni van Leeuwenhoek

• Dutch merchant• Godfather of Microbiology

– First to see live bacteria– Quote from Microbe Hunters

• Inventor microscope (hobby)– Examined water, blood, sperm,

teeth, stool, etc.– Observed tiny living creatures:

“ANIMALCULES”• No scientist

– No speculation on origin– No association with disease


Leeuwenhoek’s microscopes

• Simple or single-lens microscope– One magnifying lens– Magnifying power of x 300– Tiny glass lens mounted in a plate– Specimen placed on small pin– Screws used to adjust position


Drawings of van Leeuwenhoek

Robert Koch

• German Physician– Germ theory of disease: “specific

microbes cause specific disease”– Developed fixing, staining,

photographing bacteria– Contributed to TB skin test– Cultivate bacteria on solid agar

• obtain pure culture (one type)

• Developed Koch’s postulates– Experimental procedure– Proof germ theory of disease: “specific

microbes cause specific disease”– e.g. Antrax bacillus Antrax


Koch’s Postulates

After fulfilling Koch’s Postulates: prove that microbe is cause of particular diseaseBurton’s Microbiology: Chapter 1

Edward Jenner

• British physician and scientist• 1976: Developed smallpox vaccine

– Hypothesis: “Having cowpox protects from smallpox”

– Vaccin: sample from milder cowpox– First to publish results of vaccination– Origin of immunology?


Louis Pasteur

• French Chemist– Fermentation process– Disproved abiogenesis

(sponteneous generation)– Aerobes/Anaerobes– Developed Pasteurization– Germ theory of disease: “specific

microbes cause specific disease”– Championed changes in hosptial

practices: minimize spread disease– Vaccins for chicken cholora, antrax

and rabies.• Research center for

infectious disease


Joseph Lister

• British surgeon– Asepsis (without infection)– Antisepsis (against infection)

• “Phenol as antiseptic”– Apply to wounds, hands, instruments,

wound dressings– Perform surgery in phenol mist (irritating)

• Use of sterile equipment• ↓ wound infections/mortality• First pure culture (in liquid medium)

Burton’s Microbiology: Chapter 8,12

Alexander Fleming

• Scottish bacteriologist• First antibiotic

– Accident: mould (fungi) on bacteria culture plate

– Antibiotic (Penicillin) produced by mould inhibited growth of bacteria!

• WWII: Penicillin saved thousands of lifes


Ronald Ross

• British medical doctor (born in India)– Discovered malarial parasite in

mosquito– Realization: “Malaria transmitted by

mosquitos”

Ignaz Semmelweis

• Hungarian physician• The Father of Handwashing

– Many women died from puerperal fever (childbed fever)

– Physicians directly from autopsy room to delivery clinic

– Spread by hands of physicians/students– Rule: “wash hands with antiseptics”– ↓ Maternal mortality rate


Career in Health Care

• Bacteriologist (Bacteria)• Phycologist (Algae)• Protozoologist (Protozoa)• Mycologyst (Fungi)• Virologist (Viruses)

• Pursue career in medical microbiology?– Study pathogens, infectious diseases

and body’s defense mechanisms– Development of vaccines– Epidemiology (public health)– Immunology (immune system)– Clinical/diagnostic microbiology

(laboratory diagnosis)


The End

Microbiology Unit 1: Introduction

Education

Transcript of Microbiology Unit 1: Introduction