Epidemiology for nursing

1. Duhok polytechnic university
Shekhan technical college of health
Public health department
2nd stage
INCUBATION PERIOD
Prepared by :
Rathwan misle
Saher aswad
Zedo saido
Academic year: (2022-2023) Date:25/10/2022
Supervised by :
Dr. Alaa N. Sarkees
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2. Contents
 Terms of disease transmission
 Factors influencing incubation period
 Types of Incubation Period
 Importance of IP
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3. Terms of disease transmission:
Incubation period :
Time between transmission
of the agent and the first
symptoms of the disease.
Latent period : Time
between transmission of the
agent and the start of
infectiousness.
Infectious period :
period when an infected
host can transmit the agent
to another host.
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4. • If the latent period is longer than the incubation period,
individuals are contagious only after the onset of
symptoms
• If the latent period is shorter than the incubation period,
people are contagious before presenting symptoms
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5. Factors influencing incubation period:
• Generation time of pathogen
• Infective dose
• Portal of entry
• Individual susceptibility
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6. Types of Incubation Period
Short IP (2-3 days)
Food poisoning
Cholera
Dysentery
Influenza
Medium IP (10-21 days)
 Typhoid Fever
 Chickenpox
 Measles
 Mumps
Long IP (weeks-months-years)
Hepatitis B
Rabies
Leprosy
 AIDS 6

7. Importance of IP:
1) Tracing source of infection and
contacts:
This is use in diseases with shorter IP,
Food poisoning, dysentery, typhoid fever
Not particularly useful in diseases with
Longer IPs
2) Period of surveillance:
Helps in determining quarantine period
which is equal to maximum IP
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8. Importance of IP:
3) Identifying point source or propagated
epidemic:
In point source epidemic all cases fall
within the same incubation period
In propagated epidemics cases fall longer
than IP
4)Prognosis:
Shorter the IP, worse the prognosis
(tetanus, rabies)
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9. References
 Chan, Miranda; Johansson, Michael A. (Nov 30, 2018). "The
Incubation Periods of Dengue Viruses". PLOS ONE. 7 (11):
e50972. Bibcode:2012PLoSO...750972C.
doi:10.1371/journal.pone.0050972. PMC 3511440. PMID
23226436.
 Food poisoning symptoms & treatments - Illnesses &
conditions | NHS inform". Nhsinform.scot. 2020-02-26.
Retrieved 2020-05-07.
 World Health Organization (WHO), Severe acute respiratory
syndrome, www.who.int. Accessed 2012-05-28.
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10. THANK
YOU
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