Various modes of transmission of outbreaks in epidemiology. That includes direct transmission, point source, propagated outbreak, common source outbreak or mixed epidemic.

1. MODES OF OUTBREAK TRANSMISSION
( DISEASE TRANSMISSION)
Prepared by: Anish Dhakal (Aryan)
MBBS Student
Patan Academy of Health Sciences
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3. Modes of disease
transmission
Direct transmission
1) Direct contact
2) Droplet infection
3) Contact with soil
4) Inoculation into
skin/mucosa
5) Transplacental
( Vertical)
Indirect transmission
1) Vehicle borne
2) Vector- borne
3) Air borne
4) Fomite borne
5) Unclean hand and
fingers
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4. DIRECT TRANSMISSION
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o Direct contact  Droplet infection

5. DIRECT TRANSMISSION…
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 Contact with soil  Inoculation into skin/Mucosa

6. DIRECT TRANSMISSION…
 Transplacental ( Vertical)
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7. INDIRECT TRANSMISSION
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 Vehicle borne  Fomite borne

8. INDIRECT TRANSMISSION…
AIR BORNE
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 Droplet nuclei  Dust

9. VECTOR BORNE
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 Mechanical  Biological

10. INDIRECT TRANSMISSION…
 Unclean hand and fingers
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11. MODES OF OUTBREAK TRANSMISSION
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 Common source
 Point
 Continuous
 Intermittent
 Person to person
 Index case with limited spread
 Propagated
 Mixed
 Other

12. POINT SOURCE OUTBREAK
 Single event
 Common incubation period
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13. CONTINUOUS COMMON SOURCE OUTBREAK
 Broader incubation period
 Exposure to the source is prolonged
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14. INTERMITTENT COMMON SOURCE OUTBREAK
 Could be seasonal or weather related or a result of
common exposure
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15. PROPAGATED OUTBREAK
 People are infected through a source and ultimately
they become source too
 No. of people increases in every generation
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16. INDEX CASE WITH LIMITED SPREAD
 Single index infects other people
 Outbreak wanes when the infected people no longer
transmit the infection to other susceptible people,
perhaps because of successful control measures
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17. MIXED EPIDEMIC
 Features of both common-source epidemics and
propagated epidemics
 Common-source outbreak followed by secondary
person-to-person spread
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