Epidemiology of infections and quality concepts by Dr.T.V.Rao MD

1. Epidemiology of Infections and
Quality concepts
Dr.T.V.Rao MD
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 1

2. Epidemiology of Infectious
Diseases
•Epidemiology is ‘the study of the occurrence,
distribution and control of disease in
populations. The risk of infection is not just
dependent upon an individual’s susceptibility but
on the level of disease within the population, the
degree of population mixing and herd immunity,
as well as specific features such as the
communicable period, route and ease
(infectiousness) of transmission.
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 2

3. Learning Objectives Epidemiology of
Infectious diseases
• Define key concepts of infectious disease epidemiology
• Explain the relationship of an infectious agent to its host and
the environment
• Describe different modes of transmission
• Understand how common infectious agents are classified
• Describe the role of vaccination and other control
measures in preventing disease spread
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4. What is Infection
• Entry and development or
multiplication of an infectious
agent in the body of man or
animals
• Bacteria Virus Fungus and
Parasites
Does not always cause illness
Do you know we have 10x
bacteria in our body thanour
own cells
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5. Infectious Disease (ID) Epidemiology
•The epidemiology of
infectious disease (ID)
involves study of the
prevalence, incidence
and determinants of
infections in
populations.
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6. What is Prevalence
• Prevalence refers to
the total number of
individuals in a
population who
have a disease or
health condition at
a specific period of
time, usually
expressed as a
percentage of the
population.
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7. Knowing Prevalence Rate helps to take
corrective Measures
• Global prevalence of
hepatitis B virus (HBV)
infection may be higher
than previously reported;
therefore, all regions must
substantially scale-up
access to diagnosis and
treatment to eliminate viral
hepatitis by 2030, according
to a study published
(Lancet Gastroenterology &
Hepatology)
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8. What is Incidence
• Incidence refers to the
number of individuals
who develop a specific
disease or experience a
specific health-related
event during a particular
time period (such as a
month or year).
• Take the example of
Influenza or dengue
fever
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9. What is an incidence
rate?
• Incidence in epidemiology is a
measure of the probability of
occurrence of a given medical
condition in a population within a
specified period of time.
Although sometimes loosely
expressed simply as the number
of new cases during some time
period, it is better expressed as a
proportion or a rate with a
denominator.
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 9

10. Definition of
incidence
proportion
• Incidence
proportion is the
proportion of an
initially disease-free
population that
develops disease,
becomes injured, or
dies during a
specified (usually
limited) period of
time.1/23/2019 Dr.T.V.Rao MD @ Epidemiology 10

11. Definition of incidence proportion
• Synonyms include attack rate, risk,
probability of getting disease, and
cumulative incidence. Incidence proportion
is a proportion because the persons in the
numerator, those who develop disease, are
all included in the denominator (the entire
population).
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12. IMPORTANCE OF Knowledge on
INFECTIOUS DISEASES
• Infectious diseases remain
one of the most important
causes of morbidity and
mortality around the world.
In addition to studying the
rates of and risk factors for
infectious disease,
ID epidemiologists implement
and evaluate interventions at
the individual and community
level to:
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13. Infection
Prevention
• Prevent infection
primary prevention and,
among those with
infections, to prevent
development of disease
(secondary prevention) or
disease-associated death
and disability (tertiary
prevention)
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14. The Nature of Infections and Need for
Microbiology services
• Infectious disease syndromes: It is important to keep in
mind that many different bacterial species may cause the
same syndrome. For example both Gram positive and
negative bacteria can cause the sepsis syndrome
characterized by fever, disorientation and shock.
In addition, the same bacterial species is capable of
causing multiple different syndromes.
For example
• Streptococcus pyogenes causes impetigo as well as toxic
shock.
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15. What is an
Epidemic
• The constant presence of a
disease or infectious agent
within a given geographic
area or population group
without importation from
outside
• When conditions are
favorable may burst into an
epidemic
• Eg: HepatitisA, Typhoid
fever, Leptospirosis,
Common cold
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16. Terms used in Infectious diseases
• Hyperendemic: the disease is constantly present at
a high incidence and/or prevalence rate and affects
all age groups equally.
• Holoendemic: a high level of infection beginning
early in life and affecting most of the child
population, leading to a state of equilibrium such
that the adult population shows evidence of the
disease much less commonly than do the children
• Eg: Malaria
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17. Sporadic
Infections
• Scattered about • The cases occur irregularly
haphazardly from time to time, and generally
infrequently • May be the starting point of an
epidemic • Eg: Polio, Tetanus, Herpes zoster,
Meningococcal meningitis
• Many Zoonotic diseases are characterized by
sporadic transmission
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 17

18. PANDEMIC
An epidemic usually
affecting a large proportion
of the population
Eg: Influenza pandemics
of 1918 and 1957,
• Cholera El Tor in 1962
• Acute hemorrhagic
conjunctivitis in 1971 and
1981
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 18

19. NOSOCOMIAL INFECTION
• An infection originating in a patient while in a
hospital or other health care facility
• Not present or incubating at the time of admission
• Not the residual of an infection acquired during a
previous admission
• Includes infections acquired in the hospital but
appearing after discharge
• Eg: Surgical wounds, Hepatitis B and Urinary tract
infections.
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 19

20. OPPURTUNISTIC INFECTIONS
• Infection by an organism that
takes the opportunity provided by
a defect in host Defence to infect
the host and hence cause disease
• • Herpes simplex,
Cytomegalovirus, Toxoplasma,
• Tuberculosis, M.avium
intracellular, Pneumocystis
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 20

21. 1/23/2019 Dr.T.V.Rao MD @ Epidemiology 21

22. IATROGENIC
(PHYSICIAN INDUCED)
DISEASE
• Any untoward or
adverse consequence of
a preventive, diagnostic
or therapeutic regimen
or procedure, that
cause impairment,
handicap, disability or
death resulting from a
physician's professional
activity or from the
professional activity of
other health
professionals
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 22

23. Consequences
of Infections
• Disease may be
serious enough to
prolong the hospital
stay, require special
treatment or actually
threaten life
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 23

24. Quality improvement in infectious
diseases
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 24

25. Improving the quality
care and prevention of
Infections a great
priority
• The measurement
and continuous
improvement of the
quality of medical
care which we deliver
has become an
important concept in
today’s health care
environment.
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26. What is Quality
Difficult to Define
• Although there is no unanimity
on how to define ‘quality’, a
widely accepted definition is: “a
continuous effort by all
members of an organization to
meet the needs and
expectations of the customer”.
Exploring this definition further
allows one to realize the
ramifications of this definition.
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27. • The continuous
effort emphasizes
the value of
striving to exceed
the existing
standards rather
than merely
attaining them,
which is a
departure from
the traditional
approach to
quality assurance.
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28. ANTIBIOTIC POLICY
RATIONALISTIC USE OF ANTIBIOTICS
NEED OF THE TIMES
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29. Antibiotic policy and
stewardship
• An antimicrobial use committee working
towards the optimal use of antimicrobials
in the most cost-efficient manner in an
institution represents a process in which
many levels of the organization are
involved (or should be involved) to
improve the quality of care delivered to
the patients and, at the same time,
satisfying the prescribing physicians
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 29

30. Laboratory
Management systems
• The laboratory
management committees
for diagnostic clinical
microbiology laboratories
with representatives from
within the laboratory
administration and
‘consumers’ of the
laboratory information
also provides an ideal
opportunity for improving
the delivery of results.
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 30

31. Hand washing is most
important component of
Infection prevention
• In infection control, rather then
focusing on rates and distributions
of nosocomial infections, efforts
are directed towards determining
the common denominator of
specific infection rates1/23/2019 Dr.T.V.Rao MD @ Epidemiology 31

32. Expanded Roles of Infection Control Teams
and Microbiology Labs
•Increasingly complex and
demanding work
Increasing resistance
Emerging pathogens
New technology
Monitoring resistance
Implementation of molecular
epidemiology
5/1/2018 Dr.T.V.Rao MD 32

33. Factors to control Infection Control
•Shift toward focused
surveillance
ICUs
Devices
Antimicrobial resistance
Control strategies are
more proactive
Active intervention
Control of resistance
5/1/2018 Dr.T.V.Rao MD 33

34. How Does Chemotherapy Increase My
Risk for Getting an Infection
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 34

35. WHO releases
frequent guidelines
• The generation of practice
guidelines for the
management of sexually
transmitted diseases,
immunization guidelines and
treatment guidelines for
specific infectious diseases
also represent efforts to
improve the process of care.
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36. 1/23/2019 Dr.T.V.Rao MD @ Epidemiology 36

37. Highlighted Research
• The infectious disease epidemiology unit encompasses
domestic and global work on the epidemiology of
emerging and re-emerging infections, global
infectious disease threats, disease surveillance,
disease detection, development of vaccines and
other prevention methods, clinical trials, and the role
of infectious pathogens in the pathogenesis of chronic non-
communicable diseases (such as cancer and cardiovascular
disease).
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38. Statement of
WHO
• According to the World
Health Organization (WHO)
there are 390 million new
Dengue Fever infections
every year and half the
world's population is at risk..
This is one of the leading
causes of serious illness and
death among children in
some Asian and Latin
American countries.
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 38

39. •Plotting these on maps, they add other factors.
We have a system that obtains over 276
variables. Weather variables, geographical
variables (and) socio-economic variables.”1/23/2019 Dr.T.V.Rao MD @ Epidemiology 39

40. •The platform was
the result of more
than two years
research effort and
several months of
machine learning
analysis.
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 40

41. Forecast of emerging
Infection trends
• It has been adopted
by the Malaysian
government and
regional governments
in Brazil and the
Philippines and its
creators claim it has
an accuracy of
86.37%. They say it is
able to provide the
exact geolocation and
date of the next
dengue outbreak, up
to three months in
advance.
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 41

42. Data forecasts Helps in
Reducing the infection rate
• Diverse data challenges:
how to control,
manage, and
manipulate the multiple
data sources relating to
infectious disease
epidemiology, known
and uncertain disease
characteristics and the
recent advance of data
management methods.
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 42

43. Methodologica
l challenges
• Methodological challenges:
Helps us how to best
integrate advanced data-
mining, disease modelling
and syndromic surveillance
methods to maximize our
understanding of emerging
and reemerging diseases
based on the multiple data
sources.
1/23/2019 Dr.T.V.Rao MD @ Epidemiology 43

44. References
• Continuous quality improvement in infectious diseasesJM Conly, MD,
FRCPCToronto, Ontario Journal ListCan J Infect Disv.4(1); Jan-Feb
1993PMC3250806
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45. THANK YOU ALL
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46. •Program Created by Dr.T.V.Rao MD for benefit of
Medical, Nursing and Health care professionals in the
developing world
•Email
•doctortvrao@gmail.com
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