Experience with PCV7 vaccination in children at risk

1. Experience with PCV7 Vaccination in
Children Characterized as “At Risk”
Prof. L.Sierrasesúmaga
Clínica Universitaria.
University of Navarra.
Pamplona. Spain.

2. Streptococcus pneumoniae (pneumococcus) remains a leading cause of serious illness
among young children worldwide and is the most frequent cause of pneumonia, bacterie-
mia, sinusitis, and acute otitis media (AOM).
165
203
61
INCIDENCE of IPD
< 2 y.

3. Can J Infect Dis Med Microbiol
2006;17(1):19-26.
> 150/100,000
> 25/100,000www.cdc.gov/ncidod/dband/abcs
INCIDENCE of IPD

4. MMWR 2000;49(No. RR-9)
X 4 X 4-10X 2-3
INCIDENCE of IPD
X 4-6

5. Levine O.S. et al. PEDIATRICS 1999; 103, e28
INCIDENCE of IPD

6. Hjuler T. et al. Pediatrics
2008;122:e26–e32
INCIDENCE of IPD

7. Pediatrics 2008;122:e26–e32
MMWR
2000;49(No. RR-9)
Lancet 1994;
344:1504
X 60 – 80
INCIDENCE of IPD

8. INCIDENCE of IPD
X 2.8 – 12.6
MMWR 2000;49(No. RR-9)

9. N Engl J Med 2003;349:435-45.
INCIDENCE of IPD

10. > 0.15 g/ml (92% - 100%)
IMMUNOGENICITY
> 1 g/ml (51% - 90%)

11. IMMUNOGENICITY
NS NS
> 9.0 μg/ml

12. IMMUNOGENICITY

13. Pediatric Infectious Disease Journal • Volume 24, Number 5, 2005
IMMUNOGENICITY

14. IMMUNOGENICITY
HIV-infected children have similar quantitative
antibody responses but poorer qualitative an-
tibody responses to the PnCV.
Pediatric Infectious Disease Journal
• Volume 24, Number 5, 2005

15. Clinical Infectious Diseases 2000;31:34–41
IMMUNOGENICITY

16. RECOMMENDATIONS
Eligible Groups
• All infants and children at least six weeks of age through 59 months old.
• Groups identified by ACIP as being at “highest risk” include: infants,
toddlers through 24 months old, children with sickle cell disease or
anatomic asplenia, chronic illnesses, immunocompromising conditions,
or HIV infection;
• Groups at moderate risk include: toddlers 24-35 months old, children of
aboriginal populations, and children between 35 and 59 months old who
attend out of home day care.
CONJUGATE VACCINE (PCV7) TO PREVENT
PNEUMOCOCCAL DISEASE

17. RECOMMENDED PNEUMOCOCCAL
CONJUGATE VACCINE (PCV7). SCHEDULE.
Recommended schedules for pneumococcal conjugate vaccine PCV7
vary with the age of the child and the presence of underlying conditions:
• As primary series all children should receive:
• a 3 dose primary series and a booster dose if vaccination is begun at
< 6 months of age;
• a 2 dose primary series and a booster if vaccination is begun between
7 and 11 months of age;
• a 2 dose primary series and no booster if vaccination is begun between
12 and 23 months of age.
• If primary vaccination is initiated at >23 months of age:
• Healthy children should receive a single dose of vaccine.
RECOMMENDATIONS

18. • High Risk Children > 23 months of age, (with functional or anatomic asplenia, HIV
infection or AIDS, chronic illnesses (chronic cardiopulmonary disease, diabetes mellitus,
or CSF leak), immunocompromising conditions (malignancies, chronic renal failure,
nephrotic syndrome, or organ transplant) or who are receiving immunocompromising
medications) should receive 2 doses of pneumococcal conjugate vaccine (PCV7).
• High Risk Children > 23 months of age, should receive a single dose of PPV23
after 2 doses of PCV7.
• Aboriginal children, 24-59 months old, who have received the PCV7, may receive
a single dose of PPV23 vaccine after conjugate vaccination.
• The recommended and minimal interval between PCV7 and PPV23 vaccines is
2 months
RECOMMENDATIONS
RECOMMENDED PNEUMOCOCCAL
CONJUGATE VACCINE (PCV7). SCHEDULE.

19. RECOMMENDED FOLLOW - UP SERIES.
SEQUENCIAL PCV7 / PPV23 SCHEDULE
• For children who are immunocompromised or who have functional or
anatomical asplenia:
• If the child is < 10 years old, one dose of pneumococcal conjugate
vaccine (PCV7) and 2 months later one dose of pneumococcal
polysaccharide vaccine (PPV23) is recommended every 3 years after
the previous dose;
• If the child is > 10 years old, a revaccination is recommended if more
than 5 years have elapsed since the previous doses.
RECOMMENDATIONS

20. EFFICACY
68%
84.5%

21. EFFICACY
Clinical Infectious Diseases 2007; 44:1428–33

22. EFFICACY
> 15 >
> 59 >

23. EFFICACY

24. EFFICACY
155
9
- 90%
144
161

25. EFFICACY

26. EFFICACY
Pediatr Infect Dis J 2004;23: 726–731
83%

27. EFFICACY
Lancet 2006; 368: 1495–502

28. EFFICACY
Limits of targeting only children with an identificable
co-morbidity
Children with IPD Children with an
identifiable co-
morbidity
75 to 90% of all IPD cases occur in healthy children
(i.e., those without any co-morbidity that might put
them at greater individual risk of IPD)
5 to 10% of all children have an
identifiable co-morbidity putting them at
high individual risk of IPD
Immunization of only children with an
identifiable co-morbidity will prevent a
small percentage of all IPD cases
All Children