presentation on smallpox made by MD. Fadi Saad Ollo

1. SMALLPOX
MADE BY MD.FADI SAAD AOLOW

2. INTRODUCTION
A highly contagious and frequently fatal viral disease.
The disease is also known by the Latin names Variola or Variola Vera, which is a derivative
of the Latin Varius, meaning "spotted", or Varus, meaning "pimple".
The term "Smallpox" was first used in Europe in the 15th century to distinguish Variola from
the "great pox" (Syphilis).
Smallpox was responsible for an estimated 300–500 million deaths during
the 20th century.
Believed to have begun in Africa and spread to India and china.
U.S.S.R. Weaponized.

3. HISTORYFirst appeared in northeastern Africa around 10,000
BC
 Skin lesions on mummies 1570-1085 BC Ramses V
In the elephant war in Mecca 568 AD, smallpox
decimated the Ethiopian soldiers
Introduction of smallpox into the new world (Carribean
1507, Mexico 1520, Peru 1524, and brazil 1555 )
facilitated Spanish conquest
Smallpox destroys Hottentots (1713)
In 1738, smallpox killed half the Cherokee Indian
population
Smallpox disrupted colonial army in 1776

4. MICROBIOLOGY
Caused by Variola virus
Belongs to the genus Orthopoxvirus, the
family Poxviridae and subfamily
Chordopoxvirinae
Single, linear, double-stranded DNA
molecules and replicate in cell cytoplasm.
Shaped like bricks and measure about 300 x
200 nm in size
Incubation: 12-14 days (range 7-17d)
2 clinical forms:
 Variola major
 Variola minor

5. MICROBIOLOGY
 Variola major
 Classic smallpox
 Predominant form in Asian epidemics
 Highest mortality (~30%)
 Variola minor
 Causes milder disease
 Discovered in 20th century
 Started in S. Africa
 Was most predominant form in N. America

6. TYPES
 Classic smallpox was considered the most communicable disease; about
30% of unvaccinated people who came in contact with the virus were
infected.
 The Hermorrhagic variety of Variola had a much higher death rate (95%)
than classic smallpox and lead to death more quickly.
 The Malignant or flat forms of smallpox affected 6% of the population
and evolved slower than the classic type of smallpox but with a death rate
of almost 100%.
 The Modified variety of Variola essentially affected people who were

7. PATHOPHYSIOLOGY
 Virus lands on respiratory/oral mucosa
 Macrophages carry to regional nodes
 Invades Reticuloendothelial organs
 White blood cells infected
 Systemic inflammatory response

8. Signs & Symptoms
The initial symptoms that the person has
are fever 1030, body aches, headache,
chills and vomiting.
After the initial symptoms the virus
creates a rash that starts as macules (flat,
red lesions) on the skin. Then vesicles
(raised blisters) form and lastly pustules
(pus filled blisters) appear.
Just after the rash appears, the virus is
highly contagious as it moves into the
mucous membrane.

9. Rash Stages Of Development

10. Rash Stages Of Development

11. TRANSMISSIONAirborne route
 Initially via aerosol
 Then person-to-
person
 Hospital outbreaks
from coughing patients
 Highly infectious
Infectious materials:
Saliva
Vesicular fluid
Scabs
Urine
Conjunctival fluid
Possibly blood
The virus can cross the placenta, but the incidence of
congenital smallpox is relatively low.
Smallpox transmission does not occur through animals
or insects.

12. PREVENTION
• The smallpox vaccine is the only known way to
prevent smallpox in an exposed person. The
smallpox vaccine helps the body develop
immunity to smallpox.
• Isolation of patients if they develop fever.

13. CONTROL STRATEGIES
Smallpox hospitals (Japan 982 AD).
Variolation 10th century.
Quarantine 1650s.
Home isolation of smallpox in Virginia 1667.
Inoculation and isolation (Haygarth 1793).
Jenner and widespread practice of vaccination throughout Europe
and rest of the world.
Mass vaccination.
Surveillance containment.

14. EPIDEMIOLOGY
Smallpox reached Europe between the 5th and 7th centuries
According to one estimate smallpox was claiming 400,000 European
lives a year by the end of the 18th century – at a time when the
population of the continent numbered less than 200 million.”
In the last decade of the 18th century, life expectancy was 32 in France
and 40.5 in Denmark. Assuming an average life expectancy of 35 means
that of the 200 million people 5.7 million died per year. This means that
smallpox was the cause of death of 7% of Europeans at that time

18. TREATMENT
No proven treatment.
Only thing done was to give them intravenous fluids and medicine
to control fever and pain.
Antibiotics, given to prevent possible bacterial infections.

19. VACCINATION
Edward Jenner demonstrated that immunity
to smallpox could be produced by inoculating
a human with material from a lesion on the
udder of a cow. Jenner called this infectious
material vaccine, and the procedure came to
be called vaccination.
The material Jenner used for his vaccine
probably contained cowpox virus, a virus
related to Variola but not as virulent.

20. VACCINATION
Smallpox (vaccinia)
vaccine dryvax®
 Lyophilized vaccinia
containing calf lymph.
 Trace amounts of
antibiotics:
 Polymyxin B.
 Streptomycin.
 Chlortetracycline.
 Neomycin.
 1796 edward jenner develops vaccine
 1805 use of cows to produce vaccine
 1940s freeze-drying technology
 1965 licensure of bifurcated needle
 1972 routine vaccination stopped in u.S.
 1983 vaccine removed from civilian
market

22. Thanks