Answers Your Questions
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IPV be given in the arm before one year of age?
Yes. IPV can be given by the intramuscular (IM) or subcutaneous
(SQ) route. It can be given by the SQ route into the upper-outer
triceps area of an infant, if necessary. This can be especially
helpful to remember when you're giving multiple vaccines in
any one visit. ACIP
General Recommendations (see page 12) (2/20/03)
is the relation of the SV40 virus to Polio vaccine? We hear
about this in the media sometimes.
SV40 is a virus found in some species of monkey. Soon after
its discovery in 1960, SV40 was found in polio vaccine.
More than 98 million Americans received one or more doses of
polio vaccine during the period 1955-1963, when some of the
vaccine was contaminated with SV40. SV40 has been found in certain
types of human cancers, but it has not been determined that
SV40 causes these cancers. The majority of evidence suggests
that it does not, but some research results are conflicting
and more studies are needed. For further information, please
visit this website: NIP
SV40 Webpage. (2/20/03)
does the graph depicting incidence of polio flatten out prior
to the introduction of OPV and not after?
Millions of doses of IPV were administered when the vaccine
was licensed, leading to a tremendous decline in polio infections.
The subsequent introduction of OPV sustained this decline and
led to the eventual eradication of wild polio virus transmission
in the United States and many other parts of the world. Pink
Book Chapter: Poliomyelitis (see page 74) (2/20/03)
there any circumstances when a fifth dose of polio vaccine is
Yes. If upon record review you find that a dose was given before
the minimum age of 6 weeks or if any doses were given before
the minimum interval of 4 weeks, then you may need to repeat
an invalid dose. Also, if all 4 doses are given before 4 years
of age and school law requires a dose after age four, you may
have to give a 5th dose. Finally, adults who completed their
series as children and are traveling to a polio endemic area
may receive a single lifetime booster dose of IPV. ACIP
Polio Recommendations (see page 13) (2/20/03)
3 doses of IPV confers 99% immunity and we only give adults
a 3-dose series, why is it necessary to give children a 4-dose
series? This sometimes means that we have to give a 5th or 6th
dose if the 4th dose was given before the 4th birthday.
To some extent this is a phenomenon that is driven by a state’s
immunization requirements. It’s really a case of hedging
the bet in case the child did not develop antibodies to the
2-month-old dose. Maternal antibodies don’t have much
impact on inactivated vaccines, but they may reduce the immune
response by a little. Giving 4 doses is a conservative approach.
see children, especially immigrants, who have received multiple
doses (up to 6-8 doses total) of OPV. If they have more than
4 doses of OPV given before age 4, is it necessary to give an
additional dose of IPV after age 4.
ACIP recommends that the 4th dose in the polio series should
be given at the time a child enters kindergarten or first grade
(4-6 years of age). But if the child has received a total of
four doses of any combination of OPV or IPV at least 4 weeks
apart, the child does not need a fifth dose at school entry.
Some states' school entry regulations require at least one dose
of polio vaccine to be given on or after the fourth birthday,
regardless of the number of doses given before the fourth birthday.
Polio Recommendations (see page 12-13) (2/30/03)
is the IPV schedule for a child 7 years of age or older with
no immunization record.
In this situation the catch-up schedule should be used. The
child will need 3 doses of IPV with each dose separated by 4
Pediatric Catch-up Schedule (2/20/03)
12-year-old child received OPV #1 in 11/90, OPV #2 in 11/91,
and IPV on 3/05/03. Is the polio series complete or does this
child need another dose of polio?
This child needs one more dose of IPV. Whenever OPV and IPV
are used in the same series, a complete series is 4 total doses,
even if those doses are spread over several years. If the child
had received all OPV or all IPV and a dose was given after age
4, we would not recommend an additional dose unless the person
were going to travel to a polio endemic area. ACIP
Polio Recommendations (see pages 12-14) (2/20/03)
dose one in the vaccination series is Pediarix (DTaP, IPV, Hepatitis
B) and the second dose in the series is separate DTaP, IPV,
and Hepatitis B vaccines, does the IPV count since it is a different
IPV than the one in the combined Pediarix vaccine?
Yes, all doses in the combined vaccine and the separate vaccines
can be counted as valid doses as long as none of the doses violate
minimum age and minimum interval guidelines. These vaccines
are all licensed by FDA. (2/20/03)
do we immunize people in other countries with OPV? The hygiene
is so much worse and the living conditions are poor. Why are
we not using IPV?
There are several reasons. OPV is cheaper and easier to administer
than IPV. The shedding of the virus in the stool to contacts
is beneficial in an area where the disease is endemic or has
recently been endemic because it enhances herd immunity. Current
supplies of IPV are also inadequate to meet the needs of polio
eradication efforts in other countries. As combination vaccines
including IPV become available in other countries and the risk
of vaccine associated paralytic polio (VAPP) begins to outweigh
the risk of wild polio virus infection, especially in countries
with high rates of HIV, OPV will very likely be replaced with
a child developed polio after OPV vaccine, does the child, who
is now a teenager, need the IPV vaccine?
Yes. The child is only immune to the strain of polio with which
he was infected. There are 3 strains of polio virus in both
OPV and IPV. The child still needs protection against the other
two strains of polio. He should receive 3 doses of IPV, inactivated
polio vaccine. The minimum interval between all doses is 4 weeks.
is the incidence of vaccine associated paralytic polio (VAPP)
in the developing world?
The overall risk of VAPP in developing countries has been estimated
to fall in the range of 1 case per 1.5 million doses administered
(Latin America) to 1 case per 4.6 million doses administered
(India). These are the only two developing countries/regions
with published studies on this topic. Work is currently in progress
to estimate risk of VAPP per million birth cohort, which will
provide numbers that are potentially more useful to policy-makers
in the future. (2/20/03) More Information
Type II Polio has been eradicated, will they be changing the
composition of OPV. It seems that if the Type II was taken out,
then polio could be eradiated in about 30% less time with 30%
fewer resources. I know getting a new vaccine approved in the
USA is quite a process, but could it be done cheaper and more
quickly in another country?
There is no OPV vaccine of any type licensed or used in the
U.S. now. There has been some discussion about monovalent and
bivalent vaccines as part of the end-game strategy but this
is just in the discussion phase right now. (8/21/03)
reason you find children from other countries with multiple doses
of polio vaccine isn’t because they don’t know what
they are doing. You are witnessing the polio eradication program
in action. They basically vaccinate every child in the entire country
who is five years of age or younger on the same day. They do this
for several cycles on two immunization days each year. Therefore,
you are going to see kids with 4, 5, 6, or more polio doses.
has not been a lot of research on this question in developing countries.
Citations for two published studies are given below. VAPP risk is
estimated in terms of number of VAPP cases per OPV doses distributed,
per first OPV dose distributed, or per birth cohort. Some studies
have also tried to separate out “recipient VAPP” (that
occurring among persons who have documented receipt of OPV) and
“contact VAPP” (occurring among persons without direct
receipt of OPV, but assumed to have resulted due to contact with
another person who received OPV). All of these numbers are estimates;
there are challenges inherent in the methodologies used to come
up with these estimates that would require reading the original
papers to understand strengths and weaknesses.
Kohler KA, Banerjee K, Hlady WG, Andrus JK, Sutter RW. Vaccine-associated
paralytic poliomyelitis in India during 1999: decreased risk despite
massive use of oral polio vaccine. Bull WHO 2002;80:210-6.
JK, Strebel PM, de Quadros CA, Olive JM. Risk of vaccine-associated
paralytic poliomyelitis in Latin America, 1989-91. Bull WHO 1995;73:33-40.