Definition Eradication Criteria Successful Eradication Programs Ongoing Eradication Programs Former Eradication Programs

1. Disease Eradication The Past The
Present and The Future
By Dr Ehab Omrani
M.B.B.Ch
M.P.H (Occupational Health)
D.T.M&H(Tropical Medicine)

2. CONTENT
1. Definition
2. Eradication Criteria
3. Successful Eradication Programs
4. Ongoing Eradication Programs
5. Former Eradication Programs

3. Definition
Eradication
It is an absolute process an “ all or none”
phenomenon.
Restricted to termination of an infection
from the whole world.

4. Definition
It is sometimes confused with:
1. Elimination:
 Which used to describe of eradication of disease
from a large geographic region or political
jurisdiction
• When a disease stops circulating in a region, it’s
considered eliminated in that region.
• If a particular disease is eliminated worldwide, it’s
considered eradicated.

5. Definition
Polio, for example, was eliminated in the
United States by 1979 after widespread
vaccination efforts.
2. Further confusion arises from the use of the
term eradication to refer to the total removal
of a given pathogen from an individual (also
known as clearance of an infection).

6. Eradication Criteria
Selection of infectious diseases for eradication
is based on rigorous criteria?
Both biological and technical features
determine whether a pathogenic organism
can be (at least potentially) eradicated or not.

7. Eradication Criteria
1. The targeted organism must not have a non-human
reservoir.
 This implies that sufficient information on the life
cycle and transmission dynamics is available at the
time an eradication initiative is programmed.
 In the case of animal diseases, the infection reservoir must be
an easily identifiable species, as in the case of rinderpest),
and/or amplify in the environment.

8. Eradication Criteria
2. An efficient and practical intervention (e.g.,
vaccine) must be available to interrupt transmission
of the infective agent.
3. The disease to be eradicated should be clearly
identifiable, and an accurate diagnostic tool should
exist.

9. Eradication Criteria
4. Economic considerations, as well as social
and political support and commitment, are
other crucial factors that determine
eradication feasibility.

10. Eradication Programs
Two successful programs targeting
1. Smallpox
2. Rinderpest

11. Eradication Programs
Two former programs targeting
1. Hookworm
2. Yellow fever

12. Eradication Programs
Four ongoing programs targeting
1. Poliomyelitis
2. Yaws
3. Dracunculiasis
4. Malaria

13. Eradication Programs
 Five more infectious diseases have been identified as
of April 2008 as potentially eradicable with current
technology:
1. Measles
2. Mumps
3. Rubella
4. Lymphatic filariasis
5. Cysticercosis

14. Successful Eradication Programs

15. Smallpox
 Smallpox was the first disease, and so far the only infectious
disease of humans, to be eradicated by deliberate intervention.
 It became the first disease for which there was an effective
vaccine in 1798 when Edward Jenner showed the protective
effect of inoculation (vaccination) of humans with material
from cowpox lesions

16. Smallpox
Eradication was accomplished with a
combination of focused surveillance—quickly
identifying new smallpox cases—and ring
vaccination.

17. Smallpox
“Ring vaccination” meant that anyone who
could have been exposed to a smallpox patient
was tracked down and vaccinated as quickly as
possible, effectively corralling the disease and
preventing its further spread.

18. Smallpox
Last natural smallpox case was of Ali Maow
Maalin in, Merca/ Somalia on October 26:1977

19. Smallpox
 It is useful to consider the epidemiological factors
which have led to eradication of smallpox; these
could form the basis for eradication for other disease:
1. No known animal reservoir.
2. No long-term carrier of the virus.
3. Life-long immunity, after recovery from the disease.
4. Simple detection of cases , the rash was so characteristic and
occurred in visible parts of the body.

20. Smallpox
5. Persons with subclinical infection did not
transmit the disease
6. Vaccine highly effective, easily administered,
heat stable, and confers long term protection
7. International cooperation

21. Rinderpest
• It is a viral disease which infected cattle and other
ruminants and belonged to the same family as
measles
• During the 20th century, there were a series of
campaigns to eradicate it, through the use of a live
attenuated vaccine

22. • The final, successful campaign was led by the Food
and Agriculture Organization (FAO) of the United
Nations.

23. Rinderpest
 On 14 October 2010, with no diagnoses for nine
years, the FAO announced that the disease had been
completely eradicated.
 It is the first (and so far the only) disease of livestock
to have been eradicated by human undertakings.

24. Ongoing Eradication Programs

25. 1-Dracunculiasis; guinea worm disease
 It is a painful and disabling parasitic disease caused
by a worm, Dracunculus medinensi.
 It is spread through consumption of drinking water
infested with copepods hosting the larvae.

26. Dracunculiasis; guinea worm disease
• Guinea worm disease is set to become the
second human disease in history, after
smallpox, to be eradicated.
• It will be the first parasitic disease to be
eradicated and the first disease to be
eradicated without the use of a vaccine or
medicine.

28. Dracunculiasis
Eradication efforts have been based :
1. On making drinking water supplies safer
(e.g. through treating the water with
larvicide).
2. Containment of infection.
3. Education for safe drinking water practices.

29. Dracunculiasis
The original goal for eradication was 1995.
Two decades of eradication efforts have
reduced guinea worm's global incidence to:
more than 99.99% to 126 cases in 2014, down
from an estimated 3.5 million in 1986

30. Dracunculiasis
 South Sudan, the world's youngest nation, reported 70
cases or 56 percent of the worldwide case total in
2014.
 The remaining indigenous cases in 2014 were
reported in isolated areas of Chad (13), Mali (40), and
Ethiopia (3).

31. 2-Measles
 It is an airborne disease
 Spreads easily through the coughs and sneezes of
those infected , and contact with saliva or nasal
secretions.
 Nine out of ten people who are not immune who
share living space with an infected person will catch
it.

33. Measles
 The measles vaccine is effective at preventing the
disease?
 Vaccination has resulted in a 75% decrease in deaths
from measles between 2000 and 2013 with about
85% of children globally being currently vaccinated.

34. Measles
 In 2009 the regional committee for Africa agreed a
goal of measles elimination by 2020
 Europe had set a goal to eliminate measles
transmission by 2010, but were hindered by:
• The MMR vaccine controversy ?
• They have set a new target of 2015

35. Measles
 The Americas set a goal in 1994 to eliminate measles
transmission by 2000, and successfully achieved
regional measles elimination in 2002.
 As of February 2015, measles is no longer
eliminated in the US.
 From January 1 to April 10, 2015, 159 people were
reported to have measles.
 most of these cases [117 cases (74%)] are part of a large,
multi-state outbreak linked to an amusement park in California

36. Outbreak Response in Sudan
 5 April 2015 – The Ministry of Health of Sudan, in
collaboration with the World Health Organization
(WHO), UNICEF and other partners, respond to the
measles outbreak
 More than 1600 suspected measles cases (with 710
confirmed) have been reported from 23 localities in
12 states of Sudan.

37. Outbreak Response in Sudan
 One of the most affected states is West Darfur, with most
cases being reported among goldmine workers
 A WHO proposal to allocate US$ 3.9 million for response
activities
 Ongoing actions are being undertaken for the implementation
of initial response and containment measures including:
1. Case management
2. Alert investigation
3. Response vaccination campaigns and community health
awareness.

38. Geographic distribution of measles cases in the EMR countries by district and final
diagnosis between July 2010 and June 2011
Source : Official countries’reports

39. Measles
 At the 63rd World Health Assembly in May 2010,
delegates agreed to move towards eradication,
although no specific global target date has yet been
agreed

40. Challenges
Funding: specially for the follow-up
campaigns
National managerial Capacity:
– Inadequate number and qualification of
staff
Competing priorities:
– Polio eradication
Pockets of susceptible populations/groups
– Hard to reach populations in low
income countries
– Pockets in countries with big expatriate
population
• Security situation: rapidly deteriorating
in the EMR
– Delayed implementation of planned
activities
– Financial support
from international
partners
– Interest of the
countries
– Polio infrastructures
Opportunities
Measles

41. History of polio…
• The disease of poliomyelitis has a
long history.
• The first example may even have been
more than 3000 years ago.
• An Egyptian stele dating from the
18th Egyptian dynasty shows a priest
with a deformity of his leg
characteristic of the flaccid paralysis
typical of poliomyelitis.
3-Poliomyelitis (polio)

42. Poliomyelitis(polio)
• The World Health Assembly launched the Global Polio
Eradication Initiative (GPEI) in 1988
• Since the GPEI was launched, the number of cases has
fallen by over 99%.
• In 2013, only three countries in the world remain polio-
endemic: Nigeria, Pakistan and Afghanistan

43. Poliomyelitis(polio)
Middle East:
The most recent case reported from Syria had
onset of paralysis on 21 January 2014, while in
Baghdad-Resafa province, on 7 April 2014.
Horn of Africa
The most recent case, which had onset of
paralysis on 11 August 2014, was from central
Somalia

44. The Global Polio Eradication Initiative
(GPEI)
Objectives
To interrupt transmission of wild poliovirus as
soon as possible
To achieve certification of global polio
eradication
To contribute to health systems development
and strengthen routine immunization and
surveillance for communicable diseases

45. The Global Polio Eradication Initiative
Four Pillars of the Global Polio Eradication
Initiative Strategy:
1. Routine Immunization.
2. Supplemental Immunization Activities.
3. Acute Flaccid Paralysis (AFP) Surveillance.
4. Targeted Mop-Up Campaigns.

46. 1. Routine Immunization
• A major cornerstone of the polio eradication strategy
• According to WHO/UNICEF immunization
coverage estimates, 86% of infants received three
doses of oral polio vaccine in 2010, compared with
75% in 1990.
The Global Polio Eradication Initiative

47. Good routine OPV coverage:
1. Increases population immunity
2. Reduces the incidence of polio
3. Makes eradication feasible plan of routine
immunization for out reach areas.
The Global Polio Eradication Initiative

48. The Global Polio Eradication Initiative
2. Supplemental Immunization Activities
• Mass polio immunization campaigns that
complement routine immunization programs
are intended to:
Interrupt transmission by immunizing every
child under the age of 5 with oral polio vaccine
annually, regardless of the number of times
they have been immunized previously.

49. The Global Polio Eradication Initiative
3. Acute Flaccid Paralysis (AFP) Surveillance
• As many as 90% of people infected with the
poliovirus experience very mild or no symptoms.
• A single symptomatic case can therefore represent
a significant community-wide outbreak.
• Robust surveillance to detect and investigate
every case of polio-like AFP is essential to polio
eradication.

50. The Global Polio Eradication Initiative
4. Targeted Mop-Up Campaigns
Last stage in polio eradication
Low routine immunization coverage: very
dense or mobile populations, inadequate
sanitation, and poor access to health services
exacerbate communities’ vulnerability to polio.

51. The Global Polio Eradication Initiative
In focal areas where polio cases have been
confirmed within the previous 3 years and
circulating virus is confirmed or suspected.
In mop-up campaigns vaccinators go house-to-
house to immunize every child under 5 and
help to stop transmission.

52. The Global Polio Eradication Initiative
Before a WHO region can be certified polio-
free, the following conditions must be
satisfied:
(A) AT LEAST THREE YEARS OF ZERO POLIO CASES DUE TO
WILD POLIOVIRUS
(B) EXCELLENT CERTIFICATION STANDARD
SURVEILLANCE
(C) EACH COUNTRY MUST ILLUSTRATE THE CAPACITY TO
DETECT, REPORT AND RESPOND TO “IMPORTED” POLIO
CASES.

53. The goal of the 2013-2018 Polio Eradication
and Endgame Strategic Plan is to complete
the eradication and containment of all wild,
vaccine-related and Sabin polioviruses, such
that no child ever again suffers paralytic
poliomyelitis

54. Poliomyelitis(polio) in Libya
Libya reported the last confirmed polio case in
1991.
Routine immunization
• Routine immunization against polio has
been mandatory since 1970.
National immunization days
• National immunization days and supplementary
immunization days in high-risk areas are
conducted yearly.

55. Poliomyelitis(polio) in Libya
Acute flaccid paralysis surveillance
• National reporting started in Libya in 1997.
• Acute flaccid paralysis surveillance indicators have met
certification standards since 2002.
Laboratory
• There is no poliovirus laboratory in Libya; it is served by
the Tunisian poliovirus regional reference laboratory in
Tunisia.
• laboratory containment of polioviruses has been completed
and a report documenting the quality of containment
activities has been submitted to WHO.

56. Conclusion
• At present, polio is endemic in three countries
• Until poliovirus transmission is interrupted in these strongholds, all
countries remain at risk, as shown not only by the outbreak in
Syria, but also in recurrent outbreaks across sub-
Saharan Africa, including an ongoing outbreak in Somalia.
• But the outbreak also serves as a reminder that high vaccination
coverage is essential in countries where the disease is not currently
circulating.

57. Former Eradication Programs
Hookworm
Hookworm infection is caused by the
transmission of the hookworm parasite common
to warmer climates.
Hookworm larvae live in soil and typically enter
humans through the soles of their feet
Hookworm eradication campaign start at US in
1909

58. Hookworm
 700 million people worldwide, including 44 million
pregnant women.
 Tropical or sub-tropical environments in poverty-
stricken areas of Africa, Latin America, Southeast
Asia and China.
 In North American countries, such as the United
States, elimination of hookworm had been attained .

59. Hookworm
While regions such as Mexico still deal with
these infections from parasitic worms, WHY?
 Hookworm campaign start in the 1920s was
supposed to focus on the eradication for those living
in Mexico and other rural areas.
 However, the campaign was politically influenced,
causing it to be less successful.

61. Hookworm
 In 2001, the World Health Organization
adopted a resolution aimed at the deworming
of 75 percent of all at-risk school-age children
by 2010.
 The largest public health program ever
attempted to date.

62. Hookworm
A hookworm vaccine is also in development
and is currently in a Phase I clinical trial by the
Sabin PDP.
The 2012 WHO Road Map added 75%
coverage of all at-risk pre-school-age children.

64. Conclusion
 It is useful to consider the successful eradication
programs, these programs could form the basis for
eradication for other disease.
Both biological and technical features of the
disease should be considered before starting it is
eradication programme.
 We have to put in our knowledge the economic ,
social and political issues before setting a specific
global target date for any eradication programme.

65. THANK YOU