Introduction Of Inactivated Poliovirus Vaccine and withdrawal of Oral Polio Vaccine, Polio Eradication & Endgame Startegy 2013-2018

1. Introduction of
Inactivated
Poliovirus
Vaccine
- Sujay Bhirud

2. Epidemiology of Polio
• Polio myelitis is an acute viral infection caused by poliomyelitis
virus.
• Three types
Type 1 – most common, causes most epidemics
Type 2 – most effective antigen(no serotype detected in
world since 1999)
Type 3
• Man is the only reservoir of infection. For every clinical case
1000 subclinical cases in children and 75 in adults.

3. • Infectious material – Feces and Oropharyngeal
secretions.
• Mode of transmission – Feco-oral(major) and Droplet(in
developed countries)
• IP: 7-14 days
• POLIO: inapperent infection(72%)
mild disease (24%)
aseptic meningitis(4%)
Paralytic polio(rare<1%)

4. POLIO IS A CRIPPLING &
POTENTIALLY FATAL DISEASE
HAS NO CURE

5. Global Scenario
• GPEI(Global Polio Eradication Initiative) launched in
1988 –incidence of polio decreased by 99% from
350000 cases to 26 in 2015.
• In 1988 polio endemic countries were 125, now in
2015 only 3 –Afghanistan, Nigeria, Pakistan are
endemic.

6. Indian Scenario
• Incidence in 1970 – 4,00,000 cases.
• Vaccination against polio started in 1978 with EPI.
• In 1985 UIP was launched.
• Pulse polio Immunization programme launched in 1995.
• Incidence came down to 42 cases in 2010.
• Last case of polio due to Wild Polio Virus was in January 2011.
• SEAR certified as polio free in March 2014.

7. OPV
• Developed by Albert Sabin in 1961
• Live attenuated vaccine
• As oral drops
• Easily administered
• Provides both humoral and mucosal intestinal immunity
“SABIN VACCINE’’

8. • This intestinal immune response to opv is the main reason
why mass campaigns with OPV can rapidly stop person to
person transmission of wild polio virus
• Vaccine of choice for outbreak control

9. Three Types Of OPV
(mOPV), (bOPV), (tOPV)
• mOPV vaccines are recommended in supplementary immunization where
only WPV1 OR WPV2 is circulating
• mOPV2 stockpiles are secured with WHO for any cVDPV2 after tOPV-
bOPV switch
• bOPV is being used in India for pulse polio immunization since 2010
• Presently tOPV is the only Oral Polio Vaccine being used for the
routine immunization in OPV using countries

10. RISKS ASSOCIATED WITH OPV
Especially in areas with low routine immunization coverage
VAPP (Vaccine Associated Paralytic Polio)
-Recipient VAPP
- Contact VAPP
VDPV (Vaccine Derived Polio Virus)

11. VAPP (Vaccine Associated Paralytic Polio)
• Defined as those cases of AFP which have residual weakness
60 days after the onset of paralysis & from whose stool
sample vaccine related poliovirus but no wild poliovirus is
isolated
• Caused due to loss of attenuating mutation & reversion to
neurovirulance during replication of vaccine virus in the gut.
• Is associated with single dose of OPV to a child or occur in a
close unvaccinated or non-immune contact of vaccine
recipient who is excreting the mutated virus.

12. VDPV(Vaccine Derived Poliovirus)
• Immunized child excretes the vaccine virus for 6-8 weeks
• Some of the vaccine virus gets genetically altered during
replication knowns as VDPP
• on very rare occasions it may revert to a form that is able
to cause paralysis(VDPV) in humans
• VDPV has 3 types
1. Cvdpv(circulating VDPVs): associated with sustained
person-to-person transmission and circulates in community
with low population immunity

13. 2. iVDPV(immunodeficiency related VDPVs): in
immunodeficient patients who have prolonged
infections after exposure to OPV.
3. aVDPV(ambiguous VDPVs): isolated from
environmental sources or evidence of circulation not
established

14. • Among these three types cVDPV causes sustained
circulation. It occurs where there is low routine or
supplementary immunization coverage.
• cVDPV outbreaks have ability to become endemic,
can spread in any under vaccinated community and
can be imported to other countries.
• A fully immunized population will be protected
against both vaccine derived and wild polio viruses.

15. Birth dose of OPV
• OPV at birth is not immunogenic but it enhances
seroconversion of subsequent polio vaccine both OPV &
IPV considerably
• The first dose of OPV at a time when the infant is still
protected from maternally derived antibodies may thus
prevent VAPP
• So it is considered necessary in countries hwere the risk
of poliovirus transmission is high

16. INACTIVATED POLIO VACCINE
• IPV was developed by Dr. Jonas Salk in 1955
• Its injectable vaccine and is available only in trivalent form
• It consists of inactivated (formalin killed) strains of all three
types of polioviruses(Type 1,2,3- 40D,8D,32D antigen unit).
• It provides excellent humoral immunity but no mucosal intestinal
immunity
“SALK VACCINE”

17. • It is highly effective in preventing paralytic disease
• In the event of infection, the antibodies produced
by IPV prevent the spread of virus to CNS and
protect against paralysis.
• Studies in India shows that IPV given to OPV primed
children boosts the mucosal intestinal immunity.

18. • No risk of VAPP and VDPV
• IPV may contain formaldehyde, and traces of
streptomycin, neomycin or polymyxin. Some
formulations of IPV may contain 2-
phenoxyethanol(0.5%)
• IPV is freeze and heat sensitive vaccine. Stored
at 2-80C in the basket of ILR

19. • Liquid vaccine, no reconstitution is required
• Dose 0.5ml
• It reduces quantity and duration of virus shedding
in stool samples, which may contribute to a reduction
in transmission
• IPV is one of the safest vaccine in use

20. • IPV is not recommended for routine use in
Polio-endemic countries or in developing
countries at risk of poliovirus importations.

21. Polio eradication & endgame strategic Plan
2013-2018
The Plan differs from previous eradication plans
because it addresses paralytic cases associated with
both wild polioviruses and vaccine-derived
poliovirus/VAPP
Goal: complete the eradication & containment of all
wild, vaccine-related and Sabin polioviruses.
• refers to wild virus
Eradication Endgame
• refers to management of
VDPVs and VAPP

22. The Plan has Four Objectives
• Detect and interrupt all poliovirus transmission1
• Strengthen immunization systems, introduce inactivated polio
vaccine (IPV) and withdraw oral polio vaccines (OPV)2
• Contain poliovirus and certify interruption of transmission3
• To plan how to utilize the legacy of the fight against polio4

23. Objective 2 of The Plan addresses the
Endgame through three distinct stages
Introduce
• at least one dose of IPV
• into routine immunization
Switch
• tOPV to bOPV
Withdraw
• of bOPV & routine OPV useBefore end
2015
2016
2019-2020
Ongoing STRENGTHENING of routine immunization services

24. LEGACY BUILDING
• This strategic plan also aims at planning for the
backbone of the polio effort to be used for
delivering other health services to the worlds most
vulnerable children
• The assets, learning, capacities and workforces
developed in the fight against polio are applied to
other major public health challenges

25. Rational For The Introduction Of IPV
• Primary purpose of introducing IPV into routine
immunization is to boost population immunity against Type 2
poliovirus during & after the planned global withdrawal of
OPV2 and switch from tOPV to bOPV
• It will also facilitate the interruption of transmission with
the use of monovalent OPV type2 in the case of outbreaks
• To boost both humoral & mucosal immunity against poliovirus
Type 1&3, which will also hasten the eradication of these
WPVs
• Mitigate the risk of emergence & transmission of cVDPV2

26. IPV is not replacing OPV
It is a pre-requisite for
tOPV to bOPV switch

27. Why withdraw OPV Type2 OR
Why switch from tOPV to bOPV
• Thus, need to remove OPV2, but need to maintain population immunity
against type 2 with IPV prior to OPV2 cessation
• Type 2 wild poliovirus apparently eradicated since 1999 (last case
detected in Aligarh, India)
• New diagnostics and experience suggest that type 2 polio vaccine causes
>95% of VDPVs
• Type 2 causes approximately 40% of VAPP today
• Type 2 component of OPV interferes with immune response to types 1 and
types 3
Risks of OPV2 far outweigh the benefits

28. Rational For Introducing At least One Dose Of
IPV with OPV Schedule Prior to OPV2 Cessation
• Combined & sequential schedule of OPV and one dose of IPV
have generated high seroconvertion rate
• Number of studies have shown use of both vaccines
simultaneously better immune response than either vaccine
alone
• A single dose of IPV to children immunized previously with
tOPV who are seronegative substantially improved
seropositivity rates against type 2 & 3 wild
polioviruses(from 91% to 100%)

29. Rational for introducing single dose of
IPV at 14 weeks
• The immune response to IPV varies based on the number of doses (higher
with more doses) and the age at vaccination (higher with delayed
immunization).
• 3 doses: ~100% against all 3 serotypes
• 2 doses: ~90% against all 3 serotypes, when given >8 weeks of age
• 1 dose: ~19%-46% against Type 1, 32%-63% against Type 2,
and 28%-54% against Type 3 poliovirus.
• The immune response to one dose of IPV is substantially higher against
Type 2 poliovirus (63%) when administered at 4 months of age compared
to 6 weeks to 2 months of age (32%-39%).
• Thus, SAGE recommends a single dose of IPV at 14 weeks or first
contact afterwards, or with DTP3/OPV3/OPV4, in the EPI schedule

30. Why IPV not later than 14 weeks
• The purpose of IPV is to give infants protection
against type 2 VDPVs after tOPV-bOPV switch
• This IPV dose will be the only protection an infant
will receive against type 2 poliovirus
• So vaccinating after 14 weeks will leave child
unprotected for a longer period of time

31. • The switch is necessary because replacing tOPV with is the
key to ensuring eradication of type 2 Sabin virus which in
turn will reduce the risk of new cVDPV type2 outbreaks
after OPV type cessation, if a cVDPV2 appears
• Once the switch is made tOPV will no longer be used
anywhere in the world

32. • Routine vaccination with IPV alone should be used only in
countries with high immunization coverage(>90%) & at low
risk of wild poliovirus importation and spread
• When IPV is administered after a few doses of OPV, it not
only enhances protection against paralytic disease but also
boosts intestinal immunity even more than an additional dose
of OPV would provide.
• Combining IPV with OPV provides the advantages of both
vaccines: Strong intestinal immunity & antibody protection
against all three serotypes

33. AEFI
IPV is one of the safest vaccine in use
No serious adverse events have been reported with
IPV
Minor local reactions such as : redness & tenderness
may occur

34. CONTRATINDICATIONS
•Documented or known allergy to Streptomycin,
Neomycin or Polymyxin B
•History of allergic reaction following a
previous injection of IPV

35. Site For Injection
• Site for an injection is fixed to maintain uniformity across
the country
• It helps in seeking vaccination history in case of loss of MCP
card
• Caregiver can better recall during follow up visits
• Helps ANMs to remember & safely provide multiple
vaccinations

36. Left upper arm:-
BCG, JE
Right upper arm:-
Measles
Anterolateral aspect of
right mid thigh:- IPV Anterolateral aspect of
left mid thigh:-
Pentavac or DPT, HepB

37. Four key messages for caregivers
What vaccine was given & what disease it prevents
What minor adverse events could occur & how to
deal with them
When & where to come for next visit
Keep the immunization card safe & bring it along at
the next visit

38. IPV Key Messages for Community
• Children are still at risk of polio till it is not
eradicated from the world
• Just one dose of IPV with the third dose of OPV to
your child in routine immunization at 14 weeks of age
gives additional protection against polio
• IPV is available free of cost at RI session site

39. THANK YOU!