global polio eradication: history, achievements & challenges omar khan, md mhs

Global Polio Eradication: Global Polio Eradication: history, achievements & challengeshistory, achievements & challenges

Omar Khan, MD MHSOmar Khan, MD MHS

History & RelevanceHistory & Relevance Basics of PolioBasics of Polio VaccinationVaccination Eradication plan Eradication plan AchievementsAchievements ChallengesChallenges Personal experiencesPersonal experiences A polio cartoonA polio cartoon

OverviewOverview

History & RelevanceHistory & Relevance

The more definitions change, the more they stay The more definitions change, the more they stay the same: Polio defined in 1895 and 2005the same: Polio defined in 1895 and 2005

Poliomyelitis: Poliomyelitis: Acute inflammation of the anterior horns of the gray matter of the spinal cord, Acute inflammation of the anterior horns of the gray matter of the spinal cord, leading to a destruction of the large multipolar cells of these horns. It is most leading to a destruction of the large multipolar cells of these horns. It is most common in children, coming on during the period of the first dentition and common in children, coming on during the period of the first dentition and producing a paralysis of certain muscle groups or of an entire limb.producing a paralysis of certain muscle groups or of an entire limb.Gould’s Illustrated Medical Dictionary, 1895Gould’s Illustrated Medical Dictionary, 1895


Poliomyelitis:Poliomyelitis: An inflammatory process involving the gray matter of the cord. An acute An inflammatory process involving the gray matter of the cord. An acute infectious disease caused by the poliomyelitis virus and marked by fever, infectious disease caused by the poliomyelitis virus and marked by fever, pains, and gastro-enteric disturbances, followed by a flaccid paralysis of one pains, and gastro-enteric disturbances, followed by a flaccid paralysis of one or more muscular groups, and later by atrophy.or more muscular groups, and later by atrophy.Stedman’s, 2005Stedman’s, 2005


In 1916, New York City experienced the first large epidemic of polio, with over 9,000 cases and 2,343 deaths. The 1916 toll nationwide was 27,000 cases In 1916, New York City experienced the first large epidemic of polio, with over 9,000 cases and 2,343 deaths. The 1916 toll nationwide was 27,000 cases and 6,000 deaths. Epidemics worsened during the century: in 1952, a record 57,628 cases of polio were reported in the United States.and 6,000 deaths. Epidemics worsened during the century: in 1952, a record 57,628 cases of polio were reported in the United States.

Polio (also called infantile paralysis) was most often associated with children, but it affected teens and grown-ups as well. Between 1949 and 1954, 35 Polio (also called infantile paralysis) was most often associated with children, but it affected teens and grown-ups as well. Between 1949 and 1954, 35 percent of those who contracted polio were adults.percent of those who contracted polio were adults.

Sign from a home Sign from a home in Atlanta where an in Atlanta where an infant contracted infant contracted polio, 1941polio, 1941



1953: Pool in Elmira, New York, with sign 1953: Pool in Elmira, New York, with sign

indicating it is closed due to polioindicating it is closed due to polio

The first known polio outbreak in the United States?The first known polio outbreak in the United States?


Vermont, 1894: Vermont, 1894:

““Early in the summer just passed, physicians in certain parts of Rutland County, Vermont, noticed that an acute nervous disease which was almost Early in the summer just passed, physicians in certain parts of Rutland County, Vermont, noticed that an acute nervous disease which was almost invariably attended with some paralysis, was epidemic … and a general feeling of uneasiness … was perceptible among the people in regard to the invariably attended with some paralysis, was epidemic … and a general feeling of uneasiness … was perceptible among the people in regard to the ‘new disease’ that was affecting the children.”‘new disease’ that was affecting the children.”

-- Dr. C. S. Caverly, reporting on the first epidemic outbreak of polio in the United States, 1894 -- Dr. C. S. Caverly, reporting on the first epidemic outbreak of polio in the United States, 1894



Polio affected events, Polio affected events, lives, and peoplelives, and people


Throughout most of the 20th century, hospitals operated under strict Throughout most of the 20th century, hospitals operated under strict and orderly patient regimens. Epidemic conditions, combined with the and orderly patient regimens. Epidemic conditions, combined with the lack of a cure for polio, heightened everyone’s anxiety.lack of a cure for polio, heightened everyone’s anxiety.

During a 1934 epidemic in Los Angeles, 5 percent of doctors and 11 During a 1934 epidemic in Los Angeles, 5 percent of doctors and 11 percent of nurses who treated polio patients contracted the disease.percent of nurses who treated polio patients contracted the disease.


What’s this?What’s this?


Iron lung ward at the Massachusetts General HospitalIron lung ward at the Massachusetts General Hospital

The last cases of wild (naturally occurring) polio in the United States were in 1979 in four states, among Amish residents who had refused vaccination.

2006 is the 50th anniversary of the announcement that Dr. Jonas Salk had developed a polio vaccine: Smithsonian exhibit (below)


Evidence of sporadic epidemics of polio predate recorded history. 1789, British physician Michael Underwood provides first clinical description of the disease.

1840, Jacob Heine describes the clinical features of the disease as well as its involvement of the spinal cord.1894, first outbreak of polio in epidemic form in the U.S. occurs in Vermont, with 132 cases.

1908, Karl Landsteiner and Erwin Popper identify a virus as the cause of polio by transmitting the disease to a monkey.1916, large epidemic of polio within the United States.1921, FDR contracts polio at age 39. Although he is open about having had polio, he conceals the extent of his disability. 1929, Philip Drinker and Louis Shaw develop the “iron lung” to aid respiration.1930s, two strains of the poliovirus are discovered (later it was determined that there were three).1931, scientists create the first filter able to trap viruses.1933, FDR inaugurated president of the United States.1935, Maurice Brodie and John Kolmer test polio vaccines, with disastrous results.1938, FDR founds the National Foundation for Infantile Paralysis, known today as the March of Dimes. 1940s, Sister Kenny, an Australian nurse, comes to the U.S. to promote her new treatment for polio, using warm compresses to relax painful, contracting muscles and massage for rehabilitation. 1947 - 50, Dr. Jonas Salk is recruited by the University of Pittsburgh to develop a virus research program.

1953, Salk and his associates develop a potentially safe, inactivated (killed), injected polio vaccine.1954, nearly two million children participate in the field trials.1955, news of the success of the trials is announced by Dr. Thomas Francis in a formal press conference at Ann Arbor, Michigan, on April 12, the tenth anniversary of FDR's death. The news was broadcast both on television and radio, and church bells rang in cities around the United States.1955 - 57, incidence of polio in the U.S. falls by 85 - 90%.1957 - 59, mass clinical trials of Albert Sabin's live, attenuated vaccine in Russia.1962, the Salk vaccine replaced by the Sabin vaccine for most purposes because it is easier to administer and less expensive.1968, passage of the Architectural Barriers Act, requiring that all federally financed buildings be accessible to people with disabilities.1979, last case of polio caused by “wild” virus in U.S.; last case of smallpox in the world.1980s, post-polio syndrome identified by physicians and people who had polio.1980, the first National Immunization Day for polio held in Brazil.1981, poliovirus genome sequence published.1985, Rotary International launches PolioPlus program.1988, Rotary International, PanAmerican Health Organization, World Health Organization, Centers for Disease Control, UNICEF begin international campaign to stop transmission of polio everywhere in the world.1990, Passage of the Americans with Disabilitites Act (ADA), providing broad legal protections for people with disabilities.1999, inactivated polio vaccine replaces oral polio vaccince as recommended method of polio immunization in the United States.

“If the ability to replicate is one of life’s attributes, then polio is a chemical with a life cycle…. Viruses are ‘living’ chemicals. They have structural uniformity, like crystals, but can only self-replicate inside living cells. Poliovirus is made up of carbon, hydrogen, nitrogen, oxygen, phosphorus and sulphur; from these elements, the virus forms its RNA (ribonucleic acid) genes, and its protective protein coat.”

-- Jeronimo Cello, Aniko V. Paul, Eckard Wimmer, creators of the synthesized poliovirus, 2002

A bit about polio: basicsA bit about polio: basics

Poliovirus Poliovirus EMs EMs

A bit about polio: basicsA bit about polio: basics

Life cycle of poliovirusLife cycle of poliovirus

Affects mostly children under 3 (50% of all cases) Majority asymptomatic About 10% will get ‘minor illness’: fever, nausea, vomiting 0.5 -1% infections leads to irreversible paralysis (AFP), with maximum effect

taking place in 3-4 days Legs affected more than arms; paralysis of respiratory muscles is life-threatening Humans are the only reservoir for the poliovirus. The virus does not naturally

reproduce in any other species. Transmission is usually fecal-oral (oral-oral is possible) Virus sheds from stool for 4-6 weeks No treatment; deformity and handicap can be minimized with early PT

A bit about polioA bit about polio

A bit about (post) polioA bit about (post) polio

• Post-polio syndrome (PPS): a disorder of the nervous system that appears in people who experienced paralytic poliomyelitis, usually 15 – 40 years after the original illness.

• The main symptoms are new progressive muscle weakness, severe fatigue and pain in muscles and joints. Less common symptoms include muscle atrophy, breathing and swallowing difficulties, sleep disorders, and cold intolerance.

• Exact mechanism by which PPS causes fatigue, pain, and new weakness is not completely understood.

A bit about (post) polioA bit about (post) polio

• Possibly related to the gradual loss of individual nerve cells, and subsequent loss of nerve transmission to these fibers.

•After the original polio infection, surviving nerve cells sprout extra branches that re-attach to muscle fibers.

•Although the the muscle fibers occasionally work as well as before, some suggest that PPS develops because these extra axonal sprouts cannot “hold” forever, but instead get weaker over time due to “overexertion”.

In 1988, the World Health Assembly In 1988, the World Health Assembly (WHA) the annual meeting of the (WHA) the annual meeting of the ministers of health of all Member States ministers of health of all Member States of the World Health Organization, voted of the World Health Organization, voted to launch a global goal to eradicate polio.to launch a global goal to eradicate polio.

As a result, the largest public health effort As a result, the largest public health effort to date was put together: The Global to date was put together: The Global Polio Eradication Initiative (GPEI).Polio Eradication Initiative (GPEI).

Eradicating polio?Eradicating polio?

2 ways to get immunity: infection or 2 ways to get immunity: infection or immunizationimmunization

The live attenuated oral polio vaccine The live attenuated oral polio vaccine (OPV) was developed by Dr. Albert Sabin (OPV) was developed by Dr. Albert Sabin in 1961. The inactivated (killed) polio in 1961. The inactivated (killed) polio vaccine (IPV), was developed in 1955 by vaccine (IPV), was developed in 1955 by Dr. Jonas Salk and is an injected vaccine.Dr. Jonas Salk and is an injected vaccine.

Vaccination: the key intervention in the Vaccination: the key intervention in the GPEIGPEI

OPV (Sabin): provides immunity to all 3 strains of polio. Induces humoral immunity systemically as well as local GI mucosal immunity (which limits transmission during outbreaks).

IPV (Salk): Also induces humoral immunity via antibodies. However, it induces very low levels of immunity to poliovirus locally, inside the gut. As a result, it provides individual protection against polio paralysis but, unlike OPV, cannot prevent the spread of wild polio virus.

Vaccination: Salk vs SabinVaccination: Salk vs Sabin

IPV cannot cause vaccine-associated paralytic polio (VAPP).

OPV can, but at a rate of 1/2.5 million doses US started OPV in 1961, switched to IPV in 1999 OPV benefits for public health programs are:

– easy to give (drops) – cheap (8 cents a dose) vs IPV (almost $1/dose with

syringe, not including cost of health worker)– short term shedding of live virus from immunized kids

will likely immunize others via contact– Interrupts transmission during outbreaks due to

mucosal GI immunity

Vaccination: Salk vs SabinVaccination: Salk vs Sabin

Vaccination trend in the USVaccination trend in the US

0

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1950 1956 1962 1968 1974 1980 1986 1992 1998

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Last indigenous case

Vaccination trend in the USVaccination trend in the US

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Vaccination schedule in the USVaccination schedule in the US

VaccineIPVIPVIPVIPV

Age2 months4 months

6-18 months4-6 years

When GPEI was launched, wild poliovirus was endemic in more than 125 countries on five continents, paralyzing more than 1000 children every day

Since 1988, some two billion children around the world have been immunized against polio

Eradicating polio?Eradicating polio?

Funding: $3 billion to date The major players in the GPEI are the

World Health Organization (WHO), Rotary International, the US Centers for Disease Control and Prevention (CDC) and UNICEF.

In 1987, Rotary international launched a $120M campaign for polio

The campaign raised $247M in 1 year

Eradicating polio: fundsEradicating polio: funds

WHO: overall coordination of NIDs, SNIDs, mop-up campaigns as well as technical assistance and strategy

Rotary: advocacy and funding at the global and local country levels

CDC: technical expertise, polio surveillance, epi investgations

UNICEF: field-based support for polio vaccination as part of its own EPI (Expanded Programme on Imunizations) initiative

Eradicating polio: who does whatEradicating polio: who does what

Eradicating polio: the planEradicating polio: the plan

Interrupting transmission: 2004-5

Certifying polio-free regions 2006-8

Cessation of OPV 2006-8 Mainstreaming the GPEI 2009+

Eradicating polio: the realityEradicating polio: the reality

Interrupting transmission: 2004-5– High infant immunization coverage with four doses of

oral polio vaccine (OPV) in the first year of life - routine immunization with OPV

– National immunization days (NIDs) to provide supplementary doses of oral polio vaccine to all children under five years of age

– Surveillance for wild poliovirus through reporting and laboratory testing of all cases of acute flaccid paralysis (floppy) among children under fifteen years of age

– Targeted "mop-up" campaigns once wild poliovirus transmission is limited to a specific focal area


Certifying polio-free regions 2006-8:– Achieving certification-standard surveillance – Ensuring access to a WHO-accredited laboratory – Ensuring containment of wild polioviruses and Vaccine

Derived Poliovirus (VDPVs) – Completing the certification process (regulatory in

nature)


Cessation of OPV 2006-8– Polio outbreaks caused by vaccine-derived polioviruses

(VDPVs) have shown that continuing the use of oral polio vaccine (OPV) for routine immunization could compromise the goal of eradicating all paralytic disease due to circulating polioviruses.

– Therefore to minimize the risks associated with the use of oral polio vaccine it has been recognized that the world must stop the routine use of this vaccine as soon as possible after global certification, while surveillance sensitivity and population immunity are high.


Mainstreaming the GPEI 2009+– Minimize the perception of this being a ‘vertical

program’

– GPEI has supported the delivery of other health services, such as the distribution of vitamin A supplementation, integrated disease surveillance, supporting routine immunization services, and supporting the implementation of activities of the Global Alliance for Vaccines and Immunization (GAVI)

– Transition polio human resources and infrastructure for the use for other disease control programs

By end-2003 (I.e., in 15 years), the no. of countries with endemic polio had shrunk to 6: Afghanistan, Egypt, India, Pakistan, Niger, Nigeria.

The early leader was Latin America: PAHO (the regional WHO office) committed in 1985 to eradicate polio from the Americas

The last case in the Americas was in 1991: a 3-year old boy (Luis Tenorio) in Peru

Eradicating polio: achievementsEradicating polio: achievements

In 1995, a Global Commission for Polio Eradication was formed, and prepared regional plans which gave rise to GPEI’s current structure

In 1995, Afghanistan allowed its 3rd national 1-day ceasefire for immunizations to happen

Also in 1995, India conducted its first National Immunization Day (NID), vaccinating a historic 87M kids

The last case in China was in 1996; the last case in the Western Pacific region (the 2nd to be polio-free) was 1997 (Cambodia).


1999: more African countries, e.g. Angola and Congo, agree to cease-fires for polio campaigns.

2000: low of 719 cases 2001: low of 483 cases 2002: blip of 1919 cases, in only 7 countries;

98% of these were in India, Pakistan and Niger 2002: EURO becomes the 3rd region to be polio-

free 2006: 296 cases so far


Eradicating polio: Eradicating polio: achievementsachievements

Eradicating Eradicating polio: polio: problemsproblems

In Nigeria, some states suspended polio immunization in August 2003, following concerns regarding the safety of the polio vaccine

A new outbreak occurred, originating in one of those states, re-infecting previously polio-free areas within Nigeria

Eight previously polio-free countries across Africa were re-infected as well

Somalia is the only country in the world with a geographically expanding polio outbreak. Plagued by ongoing conflict, insecurity, lack of a health infrastructure and low rates of population immunity, it is at the top of the Global Polio Eradication Initiative's list of acute challenges.

Eradicating polio: problemsEradicating polio: problems

Increasing money being spent on Increasing money being spent on smaller number of casessmaller number of cases

Donor fatigueDonor fatigue Health worker fatigue and Health worker fatigue and

frustration: when will it be over?frustration: when will it be over?

Eradicating polio: problemsEradicating polio: problems

Nigeria (endemic) 236 India (endemic) 22 Somalia (importation) 20 Afghanistan (endemic) 6 Niger (importation) 3 Pakistan (endemic) 2 Indonesia (importation) 2 Ethiopia (importation) 2 Yemen (importation) 1 Bangladesh (importation) 1 Nepal (importation)1

Polio figures today (if today is May 2, Polio figures today (if today is May 2, ‘06)‘06)

MaMapp

Joined Pakistan and Afghanistan team in Nov. 05 for NIDs Rapidly learned why 80% of cases in these 2

countries are in about 3 provinces ‘Social determinants of health’ demonstrated daily:

cultural barriers; mistrust; resentment from Afghan/Soviet war; inequity between these impoverished areas and the rich cities

Unpredictable barriers: the largest natural disaster to his South Asia (earthquake killing 80,000) had just hit

Notes from the fieldNotes from the field

More on the resentment: mass graves More on the resentment: mass graves near Pak-Afghan bordernear Pak-Afghan border

The polio vaccination team vehiclesThe polio vaccination team vehicles

Getting there isn’t half the problem;Getting there isn’t half the problem; it’s most of itit’s most of it

Polio reservoirsPolio reservoirs

SewageSewage Drinking waterDrinking waterSewageSewage

Polio markings: an inexact sciencePolio markings: an inexact science

Finding a case (1 of 19 in 2005)Finding a case (1 of 19 in 2005)

Vaccination campaigns:Vaccination campaigns:Village in PakistanVillage in Pakistan Refugee camp in Refugee camp in AfghanistanAfghanistan

Vaccination campaignsVaccination campaigns

Empty canisters of Empty canisters of vaccine to tally upvaccine to tally up

List of potential polio List of potential polio casescases

Vaccinated!Vaccinated!

Vaccinated children’s 5Vaccinated children’s 5thth fingernail is marked fingernail is marked with purple indelible markerwith purple indelible marker

http://www.pbs.org/wgbh/aso/ontheedge/pohttp://www.pbs.org/wgbh/aso/ontheedge/polio/lio/

Polio in comic book form:Polio in comic book form:

WHO site /GPEI: WHO site /GPEI: www.polioeradication.orgwww.polioeradication.org

Polio Case Count: Polio Case Count: http://www.http://www.polioeradicationpolioeradication.org/.org/casecountcasecount.asp.asp

CDC: CDC: www.cdc.gov/nipwww.cdc.gov/nip

LinksLinks & References & References

AcknowledgementAcknowledgementWith thanks to David Heymann, Tim Brookes, and the American With thanks to David Heymann, Tim Brookes, and the American Public Health Association (APHA)Public Health Association (APHA)

global polio eradication: history, achievements & challenges omar khan, md mhs

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