infectious

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infectious
A PRESENTATIONFOR
YR 10 SCIENCE Adelaide High School
diseases
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High profile diseases
Terminology
VIRAL DISEASES V
Famous faces
BACTERIAL DISEASES B
Social context
Famous blunders
FUNGAL DISEASES F
Different cultures
Risk factors
WORM DISEASES W
Political context
Epidemics
PROTOZOAN DISEASES M
A global perspective
Killer diseases
VIROID PRION DISEASES P
History
Careers in medical science
Old wives tales
FUTURE ? PERSPECTIVES
Mindless facts
Prevention
A day in the life of a hypochondriac
War Biological warfare
Pictures
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INFECTIOUS
OUTBREAK
PUS
COMMUNICABLE
NECROSIS
EPIDEMIC
TRANSMISSION
ENDEMIC
INFECTIVITY
PANDEMIC
TOXIN
INFECTIVITY
PATHOGENICITY
HERD IMMUNITY
VECTOR
VERTICAL TRANSMISSION
PATHOGEN
ZOONOSIS
VIRULENCE
SURVEILLANCE
RESERVOIR
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Louis Pasteur
Alexander Fleming
Howard Florey
Anton van Leeuwenhoek
Robert Koch
John Snow
Click on the green arrow to find out about famous
personalities who had infectious diseases
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Creutzfeldt-Jakob
Mad Cow Disease
Trying to cure syphilis by taking mercury
Dusting with DDT to prevent typhus in Afghanistan
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• Intrinsic Factors
• Age
• Health
• Behaviour
• Site of infection
• Race (TB in Jews)
• Genetic

• Environmental Factors
• Living conditions
• Public Health measures
• Standards of care
• Climatic-environmental

Extrinsic Factors - Survival outside the host.
TB bacilli can survive in dried sputum for 6-8
months and resist common disinfectants. They can
survive sunlight, but are killed by heating.
HepB virus survives longer in a discarded syringe
than HIV.
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EPIDEMICS

• Behaviour
• Risk behaviour
• Ethical-Moral Question Is legislation an answer?
  Should carriers be locked up? Should people who
  spread HIV / SARS knowingly be prosecuted?

• Environmental Factors
• Natural Disasters
• Overcrowding
• Slums and poor health
• Lack of herd immunity

• Extrinsic Factors
• New strains
• Unexposed populations
• Drug resistance
• Point source failure
• Vaccine failure

Plague
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KILLER DISEASES
Screening for Tuberculosis TB. In some areas,
MRTB, multi-drug resistant TB, rates are 30 of
all TB cases. There is no cure for MRTB.

• MORTALITY RATES
• Smallpox 30
• Legionnaires Disease 10
• Rabies is deadly
• AIDS is fatal
• Ebola 90
• In 1347-1351, 75 million people around the world
  died from the Black Death (1 in every 3
  Europeans)
• In 1918-1919, 21.64 million people died of
  Influenza
• A burst appendix is very dangerous

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STEP BACK IN TIME
Hospitals Quarantine Immediate amputation on the
battlefield History of sanitation and rise in
living standards (polio, TB) Egyptian mummies
with leprosy and TB Bronze age villagers
In prior generations, the sight of children and
adults showing the effects of childhood paralysis
from polio was common. Often legs were paralysed.
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OLD WIVES TALES

• Shopping for tinned or canned food
• Fingers Malone, Typhoid Mary
• Gargle with salt and water (sore throat)
• Gargle with lemon and honey (sore throat)
• Dont pick your scabs
• Dont hold it in (go to the toilet if you need to)

Typhoid Fever can be spread by fecal
contamination of food or water.
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PREVENTION

• IMMUNISATION
• ENGINEERING (sewerage and clean water)
• GOOD HEALTH STATUS
• SURVEILLANCE
• ELIMINATION
• SCREENING
• ISOLATION QUARANTINE
• COMPLIANCE

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WAR biological warfare
PLAGUE bacteria
EBOLA virus
ANTHRAX bacteria
Q FEVER bacterial granuloma
SMALLPOX virus
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WAR biological warfare (cont)

• The past eg smallpox on blankets, plague bodies
• Disease epidemics that follow war
• Disease epidemics caused by war
• Diseases of armies burns, trench foot, cholera,
  typhoid

During the Boer War, typhoid killed more British
soldiers than enemy bullets 10 dead. Almroth
Wrights typhoid vaccine reduced the death rate
from typhoid in British soldiers in WW1 to 0.24
dead. During WW1, however, 10 of British
soldiers died of gas gangrene and tetanus.
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High Profile Diseases - media

• HIV / AIDS 40 million people have HIV. There
  are about 14000 new cases per day.
• EBOLA Ebola Haemorrhagic Fever kills 90 of
  those who get it.
• E coli toxins released by a deadly strain of
  Escherichia coli caused the Garribaldi food
  poisoning outbreaks in Adelaide mettwurst. Some
  died and many children suffered severe illness.
• SARS mortality rate of around 10
• ANTHRAX in 2001, in the USA, anthrax infected
  letters were sent to politicians. Postal workers
  handling mail were infected. Some died.
  Hysteria and panic caused the grounding of all
  crop dusters for months.
• MENINGOCOCCAL cases of meningococcal disease
  are frequently cited on Australian nightly
  Television news.

Meningococcal infection in the brain
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Social Context of Diseases

• Expectations
• How we view protecting ourselves society (free
  will versus legislation)
• The best strategy (compare childhood exposure
  patterns)
• Attitudes to sufferers and prejudice (lepers,
  AIDS)
• Using needles in hold-ups
• Social costs of AIDS in sub-Saharan Africa
• Fears about Genetic Modification
• an epidemic exists as much in the mind as in
  reality
• Plague in Sydney in 1900 created hysteria. The
  Chinese were blamed and persecuted. 103 people
  died. In 1867, 60 children per day died of
  measles. In the epidemic, 13000 children were
  infected, equalling 70 of Sydneys under 5s.
  748 children died in 5 months. There was
  scarcely a public reaction since childhood
  epidemics were a part of life.

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Different cultures

• Thailand 3 separate towels for upper lower
  body
• India leprosy as a special divine gift
• Arabic habit of eating with the left hand
• eating freshly killed animals
• hair removal Ancient Egypt
• cremation versus burial customs

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Political context

• sanctions surgical gloves, medicines,
  antibiotics are banned
• breakdown of the Soviet Union health services
  after the Cold War
• 1997 200 000 cases of diphtheria per year
  compared with the usual 2000

1998 in Sierra Leone troops mutilate civilians.
Both hands are amputated. Children and adults
are affected.
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Global perspectives

• burden of illness in developing countries
• global food supply industry
• (there is such large scale supply and
• distribution that infected food can
• be supplied far and wide).
• economics of monocultures
• (monocultures are more susceptible
• to infection than wild types. Our
• food crops are predominantly
• monocultures).
• drug resistance
• travel (millions of people travel each day.
• Boats dock in ports around the globe.
• Isolating areas is much harder than before).

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Careers in medical science -

• Food safety adviser
• Food Hygienist
• Health Inspector
• Policy adviser
• Customs Quarantine Officer

• Microbiologist
• Virologist
• Serologist
• Pathologist
• Public Health Officer
• Doctor, nurse, health care worker
• Histologist
• Research Officer
• Parasitologist
• Vetinarian

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Fact Sheet - microbes

• In Developing Countries, half of all deaths are
  caused by infectious diseases
• 100g of exotoxin from the bacteria that cause
  dysentery, botulism and tetanus would wipe out
  the population of the world!
• antibiotics are made by bacteria!
• after 15 hours, one bacterium can give rise to 1
  million descendants!
• tapeworms can grow up to 10 meters long inside
  adult humans!
• a huge cyst containing Echinococcus tapeworm
  larvae was removed from an Australian woman. It
  contained 8 litres of fluid!
• 1.3 billion people worldwide are believed to
  have hookworm.

Bacteria producing toxins that cause
gastroenteritis
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VIRUSES

• Plant viruses
• eg TMV, ToMV,
• Animal viruses
• eg Myxomatosis
• Rabbit Calici
• Foot Mouth
• Newcastle

• Influenza
• HIV
• Eppstein Barr
  
• Hepatitis
• MVE Ross River
• Varicella zoster herpesvirus
  
• Herpes simplex virus
• Poliovirus
• Smallpox
• Yellow Fever
• Rabies
• Rubella

Click ltENTERgt 3 times to see the HIV virus
budding from its host cell membrane
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BACTERIA

• Syphilis, Yaws Treponema
• Gastritis Helicobacter
• Burns Pseudomonas
• Food poisoning Escherichia
• Typhoid Salmonella
• Dysentery Shigella
• Cholera Vibrio
• Typhus Rickettsia
• Q-Fever Rickettsia
• Trachoma, VD Chlamydia
• Golden Staph Staphylococci
• Strep throat Streptococci
• Gangrene Clostridium
• Anthrax Bacillis
• Tetanus Botulism Clostridium
• Legionaires Disease Legionella
• TB Leprosy Mycobacterium

Salmonella
Diphtheria
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FUNGI

• THRUSH
• ATHLETES FOOT
• RINGWORM

Athletes foot (Tinea)
Thrush (Candida)
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STEP BACK IN TIME
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SOCIETY INTERPRETS DISEASE
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PRIONS and VIROIDS

• BSE (Bovine Spongiform Encephalopathy) Mad Cow
  Disease
• KURU
• Creutzfeldt-Jakob Disease
• Sheep Scrapie

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PROTOZOAN DISEASES

• Malaria (see above)
• Sleeping sickness
• Giardia
• Amoebic dysentery
• Toxoplasma
• Pneumocystis

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PROTOZOAN DISEASE Sleeping Sickness
Infected humans become perpetually weak and
sleepy. Untreated, this disease can cause death
within a year.
TseTse fly (a vector)
Trypanosomes
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PARASITIC WORMS

• Liver fluke
• Roundworm
• Hydatid cyst
• Hookworm
• Tapeworm
• Shistosomiasis
• Filariasis
• Pinworm Whipworm

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PARASITIC WORMS Filaria worm

• Filariasis Elephantitis

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PARASITIC WORMS Tapeworms
Each tapeworm is capable of producing 2500
million eggs!

• Tapeworm
• living in the gut of a cat or dog can get passed
  out in the faeces. These eggs may be eaten by a
  flea, which then colonises another dog or cat.
  The pet licks the fleas then licks a child,
  passing on young tapeworms which establish
  themselves in the gut.

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Illustrations of the manifestations of infectious
disease
HISTOPATHOLOGY
ORGAN PATHOLOGY
CLINICAL PRESENTATION
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Illustrations
HISTOPATHOLOGY
CSF containing neutrophils in a Meningitis patient
Kidney tissue infected with Staphylococci
CYSTITIS gas bubbles in tissue from gas
producing bacteris
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Illustrations (page 2)
HISTOPATHOLOGY
Cystitis massive neutrolphil presence and tissue
sloughing
Urothelial cell with attached bacteria (UTI)
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Illustrations (page 3)
HISTOPATHOLOGY
Gonorrhea a STD The bacteria have been
ingested by the bodys defence cells.
Meningococci
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Illustrations
ORGAN PATHOLOGY
GINGIVITIS
CHLAMYDIA
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Illustrations
ORGAN PATHOLOGY
PERTUSSIS
CHLAMYDIA psittaci
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Illustrations
ORGAN PATHOLOGY
CHICKEN POX WOUNDS INFECTED BY GOLDEN STAPH
TINEA
LEPROSY HAND
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Illustrations
CLINICAL PRESENTATION
Severe MENINGOCOCCAL rash
A patient with chronic lymphocytic leukaemia is
severely affected by Herpes zoster rash and
chicken pox.
LEPROSY
SMALLPOX
DIPHTHERIA Bull Neck
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Famous people who died of Infectious Diseases
King Louis XIV of France, the Sun King, one of
the most famous of all rulers died after three
weeks of severe pain from gangrene in his leg.
Al Capone, a notorious Chicago gangster, died of
syphilis.
Rasputin - syphilis
King Henry XIII of England - syphilis
King Louis XIII of France died from ulcers.
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Future perspectives

• The nature of infectious disease in the future is
  likely to depend on how we respond to the
  challenges of . . .
• drug resistance (antibiotic over-prescription,
  non-compliance, complacency)
• natural and man made disasters
• an ageing population (more susceptible to
  infection, less protected by vaccination, more
  likely to be on medication, sometimes less
  capable of maintaining high hygiene standards)
• increasing prevalence of cancers which are
  accompanied by immunosuppression and an
  immunocompromised state
• climate change and its impact on rainfall
• very mobile populations (refugees, travellers,
  asylum seekers)
• humans clearing the land and encroaching on wild
  populations
• research (eg the role of microbes as causes of
  cancer Helicobacter pylori)
• increased population density