• Enterovirus subgroup- Picarnoviridae family
• Inhabitants of the GI tract
• 3 serotypes polio virus
• IP-7 to 14 days
• Transmission is possible as long as the virus is
shed. Highly infectious in the absence of
• Man is the only known reservoir of infection.
• Fecal oral route transmission, oral – oral
transmission is also possible.
• Upto 72% of all infections in children are
asymptomatic- sheds virus in stools
• 24% Low grade fever,sore throat with out CNS
invasion- abortive polyomyelitis
• Fewer than 1 % of all polio cases results in
• Many patients with paralytic poliomyelitis
recover completely. Weakness or paralysis
present for >12 weeks will stay permanent.
Types of paralytic polio
• Spinal polio- most common, asymptomatic
paralysis often involving the legs.
• Bulbar polio- leads to weakness of muscles
innervated by cranial nerves.
• Spinobulbar polio- a combination of
• Virus isolation: from stools and rarely from
CSF or Blood.
• RT-PCR or Genomic sequencing - for
distinguishing from “wild type” or “vaccine
• No treatment
• Can be prevented through effective
• First vaccine Salk vaccine in 1955
• Trivalent Sabin vaccine in 1961
• Consists of formalin
virions of all 3
• Contains live attenuated
Polio virus 1,2 and 3.
VAPP ,VDPV& cVDPV
• VAPP- Paralytic disease occurring in vaccine
recipients, or contacts of recipients immunized
• VDPV-Vaccine virus genitally reversed to
neurovirulent Virus known as VDPV and
transmitting to unvaccinated children causing
• cVDPV- If one genotype of VDPV is detected in
two or more children with polio.
WHO South East Asian Region
3. Democratic People's
Republic of Korea
9. Sri Lanka
27 March ‘14
Total cases WPV cVDPV
Globally 27 0
in endemic countries 27 0
in non-endemic countries 0 0
Global polio status
3 Endemic countries
Hyper endemic polio era
• Incidence in India were the highest reported
anywhere (2 – 4 lakhs cases).
• Post independence India targeted diseases like
TB , Malaria, Leprosy and Kala azar but not
• Inspite of the availability of IPV in 1955,OPV
was imported in 1962.
• EPI was launched to protect from 6 vaccine
• Achieve a vaccination coverage of >80%
• India began the attempt to control polio by
immunization only in 1978 .
• WHO launched EPI in 1974.
Introduction of OPV didn’t cause
any decline in cases.
Factors lead to EPI failure
1. Coverage of 80% vaccination was achieved
2. Low vaccine efficacy
3. Provocation poliomyelitis
Recommendations to improve
• At least 5 dose polio immunization
• Giving the doses in pulse fashion
• IPV given intra dermaly in fractionated doses
• Later ,> 80 % 3 dose OPV coverage-result in
improved vaccine efficacy and indirect herd
• 1988, WHA – target polio for global eradication
by 2000.(125 countries endemic)
1. maintaining high coverage of vaccination with at
least three doses of live oral polio vaccine
2. providing supplemental rounds of vaccination
3. establishing an effective mechanism for the
surveillance of acute flaccid paralysis (AFP)
4. house-to-house OPV “mop-up” campaigns
carried out at the final stage in a limited
• Polio burden had not reached control status in
• Polio cases were estimated to be > 22 lakhs
from 1980 through 1990.
• To certify as polio free in 2000,India should
report zero case by 1997.
Factors lead to the burden
• Serious under reporting of cases continued.
• EPI could only deliver vaccine ,not measure or
monitor the disease burden.
• GOI relayed on EPI to achieve the target even
after data showed the national policy was
Era of Eradication
1 1995- 2000
3 2005 to Rukhsar
• India’s effort to implement polio eradication
started only in 1995 targeting eradication by
• PPI of children under 5 years at fixed booths on 2
National Immunization days, separated by six
weeks during the winter months.
• WHO,UNICEF,CDC and Rotary International
designed a modus operandi for India
• Launches the NPSP in 1997,a collaboration of
WHO and GOI.
Lessons from EPI failure
1. Failure to vaccinate
2. Failure of vaccination
3. Lack of nation wide surveillance
Failure to vaccinate
• Nation wide PPI campaigns 1995-1999, WPV2 stopped
circulating by 1999 October.
• In 1999,India was divided into high, medium and low risk
• Sub-national vaccination rounds were conducted in high
and middle risk states.
• In order to improve the coverage of vaccination House to
house immunization was started in 1999 to actively search
and vaccinate missed children.
• Founded in 1997- the heart of India’s polio
• Active surveillance of AFP cases in the entire
• IEAG revised quality of AFP surveillance to at
• Unfortunately, even as >10/100,000 were
• Nation wide PPI campaigns stopped the
transmission of WPV2 by October 1999. last
case was in Aligarh, Uttar pradesh.
• WPV circulation was limited essentially to the
two Northern states of Bihar and UP.
• India declared 2005 as the target year for polio
eradication in the National Health policy.
• Adopted a ‘Virological scheme’ in place of clinical
classification of AFP cases.
• Environmental sewage specimen testing started in
• Expanded its network with more than 200 SMO.
• Increased sensitivity- the program soon became
able to detect any poliovirus transmission anywhere
in the country.
Virologic Classification Scheme
Wild Poliovirus Confirm
No Wild Poliovirus
2 Adequate Stool
Died or Lost to f/u
• House to house vaccination strategies were
• Identification of missed children- the little
finger of the left hand was marked with
• Transit vaccination- teams stationed at bus
stands, railways stations, highways etc.
• Social mobilization network was launched in
UP and Bihar- to generate community support
for polio immunization.
• Convergence-to generate acceptance among
• Under served strategy- targeting poor
Social mobilizing Network
• Launched in 2001 to generate community support.
• Community mobilizers work with local medical
practitioners, religious leaders, school teachers
and others to influence local people in support of
• Mobilized communities house by house to accept
OPV and other health interventions.
• Celebrities like Amitabh Bachan as brand
ambassador of UNICEF motivated leaders and
community for greater progress.
• The mass following of the celebrity and his
endorsement of the polio programme is widely
recognized as being a key generator of
community support for polio vaccination.
• In addition to providing information about
OPV, the Social mobilizing network shares
2. exclusive breast feeding
3. the use of ORS and Zinc to tackle diarrhea
4. Sanitation and hygiene
Under served strategy
• A special strategy to reach the under served
• To tackle the disproportionately high
percentage of polio cases.
• Developed partnership with key muslim
leaders and institutions- for polio acceptance
Why Bihar and UP were high risk
• Even after several PPI and Subnational rounds
WPV transmission couldn’t be interrupted .>85%
of the cases were reported from these two states.
• 60% of WPV cases from the Muslim community.
• 32% cases of Non-Polio AFP had received 3 or
less tOPV doses
How did we target them?
• Social mobilization was first launched in UP and later
in Bihar in 2003.
• Underserved strategy
• Ulemas committee- engaged key religious leaders to
get community support for polio eradication.
• Local level microplaning
• Expanded the no. of AFP reporting units
Did we miss 2005 target too?
• 66 cases were reported in 2005.
• The virus strayed into other states as far south
as Karnataka, kerala and Tamil nadu.
1. A sensitive surveillance system to identify any
case of poliovirus transmission across the
2. The under-served strategy improved the vaccine
acceptance in the marginalized sections of the
3. Transit vaccination and house to house
immunization improved the coverage >95%
What was lacking ?
• Failure to vaccinate both under EPI schedule and
in Pulse campaigns.(Bihar-27%,Western UP-38%
and Eastern UP- 45%)
• ‘Failure of vaccine’- the extremely poor efficacy
of OPV permitted WPV transmission in western
UP and in Bihar.
• Persistent transmission attributed to failure of
vaccine and very high FOT of WPV due to the
very high density of infant population.
Vaccine and vaccination changes
• Monovalent vaccine against WPV 1 and WPV
3 were introduced.
• To counter vaccine failure and failure to
vaccinate, the number of PPI campaigns was
increased to 10 each year from 2005 and the
under-served and transit vaccination strategies
• In 2006 outbreak-638 cases of WPV1 and
28cases of WPV3
• Population immunity gap was found <2 yrs
children, due to poor UIP coverage with tOPV
and less opportunities to receive mOPV1 in
• Migrant strategy: reach out to the most
vulnerable migrant population in brick kilns,
construction sites and nomadic sites
New born tracking
• introduced in 2006- to identify, track and
immunize every new born child in the highest
risk area of UP and Bihar.
• Each child in this vulnerable area will receive
at least 8 rounds of OPV before the age of 1
year through UIP and PPI campaigns.
Targeting WPV1 WPV3
• India in 2006 prioritized elimination of WPV1
– >90 % of polio cases in the country and the
agent of re infection of a few polio free
countries and states were WPV1.
• SIA campaigns used mOPV1 and mOPV3.
• IEAG planned sequential elimination of
WPV1 first and WPV3 later.
Kosi river area intensification.
• Difficult to access area
• Satellite offices and over night stay points
were set up to reach areas were children were
Strategy against 107 blocks
• Conducted additonal mOPV3 SIA rounds while
continuing to use m OPV1 for most SIA.
• Multi pronged strategy to address polio associated
risk factors with rapid improvement in sanitation
and hygiene,availablity of clean water, exclusive
breast feeding and the prevention and control of
• By 2009 WPV1 had virtually disappeared but
due to less use of mOPV3 and poor UIP
coverage of tOPV, WPV3 outbreaks continued
• bOPV was recommended instead of mOPV3 to
address both WPV1 and WPV3.
• WPV1 recorded lowest numbers in subsequent
years and finally its transmission ceased in
1. Political will and technical leadership
2. Vaccination with a high efficacy vaccine
3. Disease surveillance and immunization progress
4. Mobilizing social and community support for
Political will and technical
• India could have achieved eradication decades
ago even before the launch of EPI in 1974.
• Application of the scientific knowledge about
the vaccine and vaccination was neglected by
• Lack of a public health department with
technical leadership only caused financial
Vaccination with a high efficacy
• tOPV had less type 1 and 3 efficacy.
• IPV was proven to highly efficacious and
many countries eradicated polio using nation
wide vaccination with IPV.
• SIA rounds with monovalent OPV against type
1 and 3 drastically reduced the transmission of
WPV1 and WPV3.
• Later SIA included bOPV and curtailed all
WPV 1 and 3 cases.
Tactics for Immunization coverage
• House to house vaccination
• Identification of missed children
• Transit site vaccination
• Congregation site vaccination
• New born tracking
• Immunization along the international borders
• Responding to polio as a public health emergency
Disease Surveillance for
immunization progress monitoring
• Polio case identification- using virological scheme
• Reporting network expansion- a large network of health
facilities over 33,700sites, including public and private health
• Increase in sensitivity of AFP surveillance- by broadening the
definition of AFP cases to make surveillance more sensitive for AFP
• Sewage sample testing
• Change in laboratory test surveillance- a new methodology of
testing the stools was introduced which takes only 2 weeks of time
compared to 5 weeks earlier.
Social mobilization as a key to
• Social mobilization network
• Migrant strategy
• Under served strategy
• Brand ambassadors and celebrities
Delay in achievement
• Lack of technical leadership at central and
• Use of less efficient OPV
• Absence of disease surveillance and laboratory
• Any eradication program should be started
with sufficient funds and financial backup
• eradication should always be targeted to a
shorter and stipulated time frame, as a long
duration leads to fatigue and decreases the
performance of the people involved
• Immunization across the international borders and
OPV vaccine certification to travel to endemic
• True polio eradication = zero transmission of WPV +
• Ethically unacceptable to use OPV after eradication-
vaccine virus-genetic reversal to neurovirulence
• cVDPV – interrupted using IPV.
• Elimination of VDPV using IPV- phase 2 polio
Risk factors of emergence of VDPV-
1. Gaps in population immunity
2. continued use of OPV.
• Introduce IPV in UIP- withdraw OPV after
achieving high coverage for IPV.
• AFP surveillance and virological investigation of
every child with AFP -continued for three
consecutive years following withdrawal of OPV.
POLIO ERADICATION END
• WHO announced the steps to complete and
conclude polio eradication in 2012.
1. Universal introduction of IPV
2. tOPV to bOPV switch
Cost and feasibility
• OPV: Rs:4 per dose
• IPV: Rs:80 – 250 per dose
• To reduce overall cost of Imported IPV
1. 2+1 schedule can be used
2. Intradermal injections in fractionated doses
• Re emergence of Polio in the post eradication
phase is anticipated.
• Cessation of OPV
• IPV manufacturing using WPV post eradication
pose some risk of inadvertent leak.
• Importation of WPV /VDPV
• Eradicating poliomyelitis:India’s journey from
hyperendemic to polio free status-T jacob john
• Polio programme: let us declare victory and move
on- Neetu Vasisht
• Global polio eradication initiative: lessons
learned and legacy- Stephan L Cochi
• The journey to a polio free India:UNICEF
• Polio eradication and end game strategic
• Polio eradication in India:Getting to the verge
and beyond:Centre for strategic and International