1. Small Pox

2. Sir Edward
Jenner

3. Definition
Acute infectious disease caused by variola virus and clinically characterised by sudden onset of fever,backache,headache,vomiting,and sometimes convulsions,esp in children .on third day of fever ,a typical rash appear which is centrifugal in distribution and passes through successive stage of macule,papule,vesical pastule and scab with subsequent scaring.

4. LANDMARKS IN THE HISTORY OF SMALLPOX4

5. LANDMARKS IN THE HISTORY OF SMALLPOX

6. Agent

7. SMALL - POX VARIOLA (ICD-10): B03 Variola :- Orthopox Virus
Large DNA virus
Types- Major
Minor

8. 5 subtypes- Modified Sp (15%) Abortive attack Haemorrhagic Sp (2.7%)-
Early : Purpura Variolas
Late : Variola pustulosa H’gica
Flat type (0.3%)
Variola sine eruption (v. rare)

9. -Mortality <1% VARIOLA Major VARIOLA Minor -Milder form
CFR 20% to 50%
Classical Small pox (82%)
VARIOLA Minor
-Milder form
-Short duration
-Mistaken for chicken pox
-Mortality <1%

10. Host Factors Host: all age groups Occupation: Medical & Nursing
Physiological:
Pregnancy & immuno-compromised

11. Immunity Immunity: life long after infection
Secondary sub-clinical cases were common
-They do not transmit infection,
Only booster the immunity

12. Source : Case of Sm. Pox,
No carrier,
Reservoir : NONE
Infectivity: Untill the scab is formed
Max. during 1st week of of Rash
S.A.R. = 35-40%

13. Environmental Factors
Low temperature & High Humidity
Virus survival increased
Season: Winter & Spring
Ventilation: Overcrowding Spread

14. Modes of Transmission
Direct: Implantation on Nasal, Oropharyngel, Mucous membrane
Secretion from the rash \scab
Indirect: Air borne, Fomite borne,
Close contact with patients, or their clothing or bedding, is thus required for infection.
The disease is spread by secretions from the patient's mouth and nose, and by material from pocks or scabs. It is transmitted directly from one person to the next. Droplet of nuclei– Particles <10 microns—remain suspended in the air & easily disseminated by an air current. 1-5 micron may get deposited in the alveoli.

15. Incubation Period 10 days -17 days
(average - 12days ) rarely 7-17 days
A patient who has developed the rash of smallpox will have been exposed to the virus about two weeks previously

16. Signs &Symptoms
Fever , Backache, Malaise, Headache, Convulsions in children , Delirium
Abdominal Colic in adults
A rash appears after 2 to 4 days and progresses through characteristic stages of papules, vesicles, pustules and finally scabs.
Scabes fall off at the end of 3rd or 4th week
The illness begins with fever. The patient feels sick and has symptoms such as headache and severe backache.
A rash appears after 2 to 4 days and progresses through characteristic stages of papules, vesicles, pustules and finally scabs. The scabs fall off at the end of the 3rd or 4th week.

17. Characteristics of lesions
Smallpox is a disfiguring disease.

18. Centrifugal distribution
Most dense
On face & extremities than on trunk
Distal part of limbs than proximal,
Extensor surface
Convexities,

19. The density of the rash is greater on the face than on the body.

20. Pocks are usually present on the palms and on the soles.

22. few raised spots called papules appear.
Day-1
few raised spots called papules appear.
Usually seen first on the face, and later on the body and extremities.
H / of patient been in contact with a smallpox case two weeks before, then one may suspect the diagnosis.

23. Day-2
more papules appear.

24. By day 3
the rash has become more distinct and raised above the skin surface.
Fluid is accumulating in the papules to form vesicles.

25. day 4,
the vesicles are more distinct , they feel very firm to the touch.
When broken, they do not collapse because the fluid is contained in many small compartments.

26. the fluid in the vesicles has become cloudy and looks like pus.
By day 5,
the fluid in the vesicles has become cloudy and looks like pus.
At this time, the fever usually rises and the patient feels more ill than before.
At this stage, the pocks are called pustules.

27. On day 7 The rash is definitely pustular. Umbilication starts
Although varying somewhat in size, all resemble each other in appearance.
The rash is now so characteristic that there should be no mistake in diagnosis.

28. the pustules increase somewhat in size.
Day 8 and 9
the pustules increase somewhat in size.
They are firm to the touch and deeply embedded in the skin.

29. The scabs begin to appear
Day 10-14
The scabs begin to appear
The scabs contain live smallpox virus.
Until all scabs have fallen off, the patient may infect others.
Gradually the pustules dry up and dark scabs form.

30. By day 20,
the scabs have come off and light- coloured or depigmented areas are observed.
Non infectious stage

31. Over a period of many weeks the skin gradually returns to its normal appearance.
Scars which last for life may remain on the face, an indication of previous infection with smallpox.

32. 3 4 5 7 9 13 Papules Vesicles Pustules Scabs
Papules are seen on days 3 and 4; vesicles on day 5; pustules on days 7 and 9; and, finally, scabs on day 13.
Scabs

33. Onset of rash FEVER RASH Pre-eruption Papules Pustules Scabs Days – 4
– 3
– 2
– 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 21
Spics of fever at each stage of rash, fever throughout untill the scab is formed

34. Complications Pustules- secondary Infection Ocular Bones & joints
Resp.-Pneumonia
Bronchitis, Pulm. Oedema
G.I. syst- Diarrhoea, Ac. Dilatation of Stomach, Infection of Intestine
GU sys- Orchitis
CNS- Encephalitis

35. Diagnosis Clinical- & Lab : Skin scab. Oro-pharyngeal, Mucous membrane
Conjunctiva,
Urine

36. Eradication

37. The eradication campaign was based on two key strategies:
(1) mass vaccination and
(2) the detection and containment of all cases of smallpox. 
Surveillance: Facial Pocks marks survey
Rumor register

38. Prevention & Control Isolation & Quarantine were used in early days
Vaccination:
Early days: Variolation
Edward Jenner (1796) - 1st Vaccination using Cow Pox
Surveillance: Facial Pocks marks survey
Rumor register

39. Sir Edward Jenner 18th century
People who survived from small pox (S.P)
did not get disease again--- Life long immunity.
Variolation- To infect healthy individual with s.p. material taken from the pustules of infected individual
Some were developing the ds. Or developed other infection

40. Hypothesis- Cow pox offers immunity to S.Pox.
Small pox epidemic
Developed Did not developed disease disease
Milkmaid women
had contact Cow pox
Hypothesis- Cow pox offers immunity to S.Pox.

41. Eradication Of Small pox
Vaccination
Administration of Cow pox material to 8 yrs. Old healthy volunteer
After 6 weeks
Inoculated from small pox pustules
No disease
Large no. of people
Results
Immunization schedule
Evaluation of the effect & coverage
Eradication Of Small pox
Vacca- cow---- First time the word vaccination was introduced

42. Vaccination
Dryvax was created in the late 1800s, by the company that became Wyeth Laboratories

43. Multipuncture vaccination by bifurcated needle
Triceps\ Deltoid Intradermal

44. Revaccination recommended at least every 10 years.
Administration-
by making 15 punctures in the skin with a special needle. 
Revaccination recommended at least every 10 years. 

45. Efficacy of vaccine- >95%

46. Vaccine Reaction

47. Organ transplant- Steroid therapy

48. Virus- Vaccines

49. Vaccination
Wyeth stopped making the vaccine in the 1980s. But government officials kept a stockpile of about 15 million doses.
The Dryvax came in handy in 2003, when it was used to help contain an outbreak of monkeypox in the United States.

50. Is vaccination needed at present?

51. Post Eradication Scenario
Possibility of infection
A- Accidental infection with laboratory associated stocks
B-Infection with animal virus--- monkey pox & tenapox virus

52. Vaccination
After 9/11 the subsequent spread of anthrax in October 2001, public health officials regard the use of biological weapons by terrorists as a real possibility. 
U.S. officials had also been worried that smallpox might resurface as a result of bioterrorism.

53. It is believed that clandestine stocks of smallpox exist in 10 or more other countries.
Today the only verified repositories of the virus are held in secure laboratories at the Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, and the State Center for Research on Virology and Biotechnology in Koltsovo, Russia. 

54.   Most recently, a CIA intelligence review concluded that Iraq, France, North Korea, and Russia have covert stocks of smallpox virus, although the French government has denied the allegation.

55. 15 months after sept.11 Bush ordered smallpox vaccine for military.
Bush said he will also be getting the smallpox vaccine.

56. vaccine is now available under limited circumstances:
  Department of Defense military and civilian personnel and State Department personnel who work in high threat areas
Healthcare providers and “first responders” who volunteer for smallpox response teams
For laboratory workers and others at risk for exposure to the smallpox virus, or closely related viruses 
Participants in smallpox vaccine clinical trials

57. Thank you