1. CHANGING PATTERN OF DISEASES
(EMERGING AND RE-EMERGING INFECTIONS)
Presented by;
Dr. Alteib Yousif Abdelgadir
Student of Public and Tropical Health
Master program - Patch 11
September 2012
2. Objectives
Key terms
Background
Emerging and re emerging infections
Potential contributing factors
Control of infectious diseases
Critical epistemology
Emerging diseases and globalization
Developing global response
3. By the end of this session, participants are
expected to have some ideas about:
Emerging diseases, key terms, history and
potential contributing factors
Control of infectious diseases
Emerging diseases and globalization
Developing global response
4. Emerging infections: An infection that has
newly appeared in a population or has previously
existed but has rapidly increasing in incidence or
geographic range
Population at risk: A population subgroup that
is more likely to be exposed or is more sensitive
to the infection than the general population
Quarantine: The practice of isolating an
individual who has or is suspected of having a
disease, in order to prevent spreading the
disease to others.
5. Infections remain a major global public health
problem
Humans originated in the tropical climate in
Africa were affected by the same parasites as
other primates in these areas.
Humans as hunters moved to more temperate
zones and the infectious agents they were
exposed to changed due to new climate.
In due time hunting gave way to agriculture and
domestic animals living in close proximity to
human...(opportunity for many zoonotic
diseases) to spread to humans
6. Increase population size and density provided
ideal conditions for further spread of person
to person spread of infections
Humans, food and water became reservoirs
for many of these infections
Trade routes became established and
movement of people and goods carried new
pathogens to susceptible populations
7. A climate of irrational fear has been a common
feature of responses to infectious diseases for
many centuries ( before and after the role of
microorganism as a causative agents).
Germ theory: Theory that all contagious
diseases are cause by microorganism ( 1870)
Control of infectious disease became through
the work of Robert Koch and Louis Pasteur and
the isolation and identification of the etiological
agent
8. Nature of infectious diseases changing not
only in magnitude but also inability of science
to provide all answers because of:
New disease notably HIV/AID, SARS
Ancient and re-emerging diseases such as
tuberculosis, diptheria ( these had
disappeared in some parts of the world)
9. New agents are being implicated in the
causation of a number of clinical syndromes;
Parvovirus B19 (causes a childhood rash
called fifth disease or erythema infectiosum
which is commonly called slapped cheek
syndrome)
Herpes viruses; herpes type 1 (oral herpes)
and herpes type 2 (genital herpes).
HPV (warts, anal lesions, genital cancer, oro
pharyngeal cancers, oral papillomas, etc
10. Many new drug resistant organisms,
unresponsive to anti microbial agents have
emerged over the last 60 years
Multidrug resistant organisms such as M.
Tuberculosis, Staph. Aureus and Salmonella
species
Bovine spongiform encephalitis decimated
the British beef industry and cost $40 billion.
11. Population growth and Poverty: more than 2
billion suffer from under nutrition or
malnutrition.
Population movement ( 150million, 2.5%,
people live outside their country of
birth),more migrants live in overcrowded
conditions
Human behavior: Changes including sexual
behavior and IV drug use
12. Non compliance by health care
workers....drug resistance
Technological development: Bovine
Spongiform Encephalopathy (BSE; Mad
Cow Disease) spread has been attributed to
technological changes in animal and food
chain dating back to the 1980s. BSE are
transmissible
Economic development and land use e.g
malaria in newly agricultural area
13. Microbial adaptation and change...Antigenic
shifts and drifts. Major epidemic are caused
by antigenic drifts
Breakdown of public infrastructure and public
policy due to war or political change.
Climate change: Vectors will be able survive in
areas where they had not.
14. Warfare/ terrorism/conflict: British in 18th
Century Distributed small pox infected
blankets to North American Indians.
Countries have sought to produce an Anthrax
bomb and increasing concern about
biological weapons
15. Involves going beyond the focus on host and
organism to socioeconomic, cultural, and
political necessary
Globalization has challenged infectious
diseases in a way that has become starker.
The role of the state has become more
important
16. Tension between the individual and the state:
compulsory HIV test for employment and
travel, compulsory immunization, Quarantine
e.g H1NI.
Many borders in African serve as semi-
permeable membranes; open to disease and
yet closed to cure.
17. What qualifies as emerging infectious
diseases?
Why do some persons constitute ‘risk group’
while others are ‘individuals’ at risk?
Can standard epidemiology, (sometimes
short on critical theory) help us to take hold
of deep socio-economic issues relating to
disease emergence?
18. Modern epidemiology is oriented to
explaining and quantifying the bobbing of
corks on the surface waters, while largely
disregarding the strong undercurrents that
determine where, on the average, the cluster
of corks end up along the shoreline of risk’
-McMichael 1995
19. Ancient trade route and early globalization
WHO in 1948 became responsible for
International Health Regulation, binding
member states regarding cholera, plague,
yellow fever and smallpox. (IHR has now been
revised enhancing timeliness and reporting)
20. IHR does not provide legal framework for
other diseases including threats of emerging
diseases
Enforcement of IHR depends on the
cooperation of governments and there are no
resources to ensure compliance such as
punitive measures
21. Good health is both essential and instrumental
to achieving human security’ (illness and death
are critical threat to human life)-The Commission
on Human Security.
Violence, infections and poverty are the three
health challenges that critically impact human
security
Bioterrorism
The potential to cause mass casualty
HIV/AIDS risk to population, military and
peacekeepers... Uganda soldiers in Somalia
22. Development of global surveillance
networks...surveillance remains fundamentally a
local activity so collaboration is needed across
borders
International mechanism for control of
infectious diseases depends heavily on
government institutions
While globalizations creates new risks it also
offers new opportunities for enhancing
communicable disease response e.g facilitating
surveillance and reporting
