Download Hib vaccine

Review of childhood and
Adolescent Vaccination 2010
Marie-Denise Gervais, M.D.
Department of Family Medicine and
Community Health
University of Miami, Miller School of Medicine
Childhood Vaccination
The impact of routine
vaccination on childhood
diseases in U.S. is considered
one of the major medical
achievements of the 20th
century…
Trends in Deaths Caused
by Infectious Disease (US)
Mortality Rates per
100,000 US Population
900
800
700
600
500
400
300
65
60
55
50
45
40
35
30
25
1980
1984
1988
1992
1982
1986
1990
1994
200
100
0
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990
Year
Centers for Disease Control and Prevention. US Dept of Health and Human Services, 1998.
Vaccine Development
Disease
Year
Disease
Year
Smallpox
Rabies
Typhoid
Cholera
Plague
Diphtheria
Pertussis
Tetanus
Tuberculosis
Influenza
Yellow fever
Poliomyelitis
Measles
1798
1885
1896
1896
1897
1923
1926
1927
1927
1945
1953
1955
1963
Mumps
Rubella
Anthrax
Meningitis
Pneumonia
Adenovirus
Hepatitis B
Haemophilus
Influenzae type b
Hepatitis A
Varicella
Lyme disease
Rotavirus
1967
1969
1970
1975
1977
1980
1981
1985
MMWR Morb Mortal Wkly Rep. 1999;48(12):243-248.
1995
1995
1998
1998
Morbidity Pre- and PostVaccinations (US)
Disease
Smallpox
Diphtheria
Pertussis
(paralytic)
Tetanus
Poliomyelitis
Measles
Mumps
Rubella
Haemophilus
Influenzae type b
Annual Morbidity
Prior to Vaccine*
Morbidity
1998
%
Decrease
48,164
175,885
0
1
100%
>99.9%
147,271
1,314
16,316
503,282
152,209
47,745
6,279
34
0
89
606
345
95.7%
97.4%
100%
>99.9%
99.6%
99.3%
20,000
54
99.7%
MMWR Morb Mortal Wkly Rep. 1999;48(12):243-248.
Principles of Vaccination
Immunity
Self vs non- self
Protection from infectious diseases
Active Immunity
Protection produced by a person’s
own immune system
Usually permanent
Trigerred by Antigens
Passive Immunity
Protection transferred from another
person or animal as antibody
Wanes over time (weeks,months)
Active immunity
 Stimulation of immune system to produce Ag-
specific humoral(Ab) and cellular immunity
through :
 Natural disease : immunity is long through
immunologic memory
 Vaccination : similar memory without the risk of
disease
Classification of vaccines
 Live attenuated
– Must replicate to be
effective
– Usually effective with
1 dose
– Severe reactions
possible
– Interference with
circular Ab
– MMR, Varicella,nasal
Flu, OPV
 Inactivated
–
–
–
–
Heat / Formalin
Cannot replicate
Requires 3-5 doses
Immune response
mostly humoral
– Ab titer falls overtime
– Principal Ag may not
be defined (hib)
– IPV,DTaP, Hep B,A
Pertussis
 Most hospitalizations and complications occur in
infants
 1/2 cases occur in infants, 3/4 in children ≤ 5y/o
 Complication: pneumonia*(15%),
seizures(2.2%) , encephalopathy (0.7%) and
permanent brain damage
 Source: respiratory droplets from adults and
adolescents
 Highly contagious
Pertussis cont’d
 Contagiosity is long (7days post exposure to 3
weeks after symptoms onset)
 Incubation: 5 to 21 days (7-10)
 Immunity is lifelong
 Transplacental immunity wanes rapidly after
birth
 Recent outbreaks in US since 1990’s
Pertussis vaccine
 DTP 70% to 90% effective.
 DTP adverse reactions: persistent crying,
unusual high-pitched cry, seizures, hypotonichyporesponsive episodes.
 Protection wanes with time ≤ 12 years.
 DTaP has1/4 to 1/2 the adverse reactions.
 DTaP not recommended after age 7.
 2006: Tdap adolescent prep 11-12 y/o.
Tetanus and Diphteria
 Hundreds of thousands of tetanus deaths
worldwide
– Only 26 cases of Tetanus in 2000 in US
– Spasms of jaw muscles( trismus) and back
muscles(opisthotonos).
 In the 1920’s, 14,000 deaths/year to diphteria
– Only 2 cases of diphteria in 2000 in US
– Tonsillitis, myocarditis, heart failure and
neuritis
Td / Tdap
 Tdap recommended for 1st booster dose then
Td every 10 years for persons ≥ 12 y/o.
 Contains same quantity of tetanus toxoid as
DTP , DTap and DT.
 Contains only 1/11 as much diphteria toxoid.
 Arthrus-type hypersensitivity reaction or fever ≥
103ºF should not receive Td more often than
every 10 years.
Haemophilus Influenzae type B
 Most common cause of bacterial meningitis in
children≤5 y/o.
 Peak incidence 6- 12 months of age.
 Meningitis has 2%-5% mortality rate even with
appropriate treatment
 Neurologic sequelae in 30% of survivors
 Epiglottitis, facial, orbital and periorbital cellulitis,
pneumonia, osteomyelitis,septic arthritis and
pericarditis.
Hib vaccine
 Hib organism is encapsulated in polysaccharide capsule.
 Unencapsulated H-flu colonize the respiratory tract
(sinusitis, otitis media, bronchitis).
 Vaccines against Hib do not protect against other strains
of Hflu.
 Immature immune systems of infants do not respond to
polysaccharide Ag
 Ag of Hib capsule is linked to other proteins (diphteria,
tetanus, meningococcal) to improve recognition.
Hib vaccine (cont’d)
 Hib not given before 6 weeks of age (may
induce tolerance to Ag)
 Efficacy 95% to 100 %
 Also decreases nasopharyngial carriage
 Unimmunized children acquire natural immunity
by age 5.
 No serious adverse reactions.
Poliomyelitis
 18,000 paralytic cases in 1954 in US.
 Last case of indigenous polio : 1979 US, 1994
Peru.
 Recent outbreak in D.R and Haiti due to a
revertant virus.
 Enterovirus, 3 serotypes, feco-oral route,75% to
95% transmission in household contacts.
 Subclinical infection(95%), non specific viral
illness(5%), nonparalytic meningitis, paralysis.
Polio Vaccines
 IPV-Salk (inactivated)
– Cannot cause VAPP
– Safe for
immunocompromized
– IM injection
– Less GI immunity
 OPV (attenuated)
– Easier administration
– Cohort effect
– Can revert and cause
VAPP ( 1 case per 2.4
million doses of OPV.)
– No longer
recommended in US
MMR
 Combination of 3 live attenuated vaccines
– Contains neomycin, gelatin, sorbitol, human albumin,
and is produced in chick cells.
 Maternal Ig persist until 9-11 months.
– 1st dose is recommended at 12-15 months.
– Ab persist ≥ 17 years (life!)
 Adverse reactions: pain ,irritation, redness.
 Specific delayed reactions:
– Measles..fever and rash.
– Mumps…transient orchitis
– Rubella…lymphadenopathy and arthralgia.
Ongoing Mumps outbreaks in
Iowa
Hepatitis B
 128,000 to 320,000 infected annually in U.S.
 HBV infection more likely to become chronic
when acquired early in life:
• 90% as infants
• 30% to 60% if less than 4 y/o
• 5% to 10% as adults
 36% of all HBV infection contracted the infection
in childhood
 HBV is the 2nd cause of cancer worldwide
Rationale for HepB vaccination
 HBV infection high morbidity and mortality.
 HBV infection from child to child reported in schools,
daycare centers, families.
 No risk factor was identified in 30% of infected persons.
 Cost effectiveness of vaccine.
 Protective Ab levels ( ≥ 10mIU) in 95% of children.
 Standing orders for Hep B vaccines at birth.
Streptococcus Pneumoniae
 Encapsulated organism, 90 serotypes
 Most common bacterial cause of meningitis*,
bacteremia, pneumonia, otitis media in US
 Incidence highest in infants then declines with
age and increases in the elderly
 Risk factors; age, race, recent use of Abx,
daycare, exposure to tobacco smoke, chronic
medical conditions; sickle-cell and HIV
Pneumococcal conjugate vaccines
 3 vaccines are available :
– Pneumovax, 23-valent, polyssacharide .
– Prevnar, 7-valent,conjucated.
- (new) Prevnar,13-valent, conjugated.
 Pneumovax ( only stimulates B lymphocytes)
not effective in children ≤ 2y/o.
 Prevnar elicits T-dependant immune response.
– $108 per dose… most expensive routine
infant immunization series to date.
– No serious adverse reaction with Prevnar.
Varicella
 4 millions cases of VZV infection per year in US.
 Hospitalization rate: 5/1000 cases.
 Death rate: 0.7/100,000 cases.
 Secondary attack rates: 90%.
 Complications: Impetigo , pneumonia , ataxia ,
encephalomeningitis, glomerulonephritis …
 Most severe in neonates and adults.
Varicella vaccine
 Live attenuated virus
 97% effective against severe disease
 85% protective for any infection; for ≥ 7years
 Less immunogenic in older children
 Ab levels have persisted 20 y in Japan
 Adverse reaction 25% after 1st dose, 47% after
2nd dose
 Possible postexposure prophylaxis
2005-10 New Vaccines
 Rota Teq: live oral rotavirus; 2- 4- 6m.
 ProQuad: MMRV
 Hepatitis A: Havrix; 2 doses 6 months apart
after 1 year.
 Influenza: expanded indication 6- 59 m (23)
 Meningococcal MCV4 age 11-12y/o
 Pediarix: (DTaP+ IPV+ HepB)
 HPV *:3 doses after age 9 (0,2,6m)
cdc.gov
cdc.gov
cdc.gov
cdc.gov
Recommended Childhood Immunization
Recommended Childhood Immunization
Catch-up Schedule
Catch-up Schedule
Thank You!