Transcript Malta - VHPB

Infant and Adolescent
Hepatitis B Vaccination
and Use of Combination Vaccines
United States
Elimination of Hepatitis B Virus Transmission
United States
Strategy
• Prevent perinatal HBV transmission
(1984 - selective; 1988 – universal)
• Routine infant vaccination (1991)
• Catch-up vaccination
• 11-12 year-old children (1995)
• All children <19 years of age (1997)
• Adults in high risk groups (1982)
Key Elements of Perinatal Hepatitis B
Prevention Program, United States
• Testing all pregnant women for HBsAg
• Reporting of HBsAg-seropositive women
• Case-management and tracking to assure:
– HBIG and hepatitis B vaccine at birth
– completion of vaccine series by age 6 months
– post-vaccination serologic testing
– identification and vaccination of susceptible HH/sex
contacts
Evaluations of HBsAg Screening
of Pregnant Women, 1991-2001
Study
New York
Kansas
National
Washington
Ohio
Illinois
California
Florida
North Carolina
Delaware
8 states (EID sites)
Year
1991
1992
1993
1994
1994
1994-5
1995
1995
1997-98
1999
2001
Births
Mothers
Reviewed, No. Screened, (%)
607
412
3,982
4,031
394
1,361
5,414
365
4726
N/A
5135
(96)
(84)
(84)
(96)
(96)
(91)
(96)
(88)
(92)
(91)
(96.5)
Percent Identified
100
19042 19250 19252 19617
80
60
40
20
19919 20254 20861
Expected
7874
8403
8002
8687
20000
15000
8841
8730
9503
Identified
0
10000
5000
0
1993 1994 1995 1996 1997 1998 1999
Year
Expected Number
Identified and Expected Births to
HBsAg-Positive Mothers
United States, 1993-1999
HBsAg Seroprevalence among Pregnant Women
by Prenatal Screening Status, Philadelphia, 1991
Prenatal
Screening
No. of Women
Tested
Yes
1555
12 (0.8)
No
208
14 (6.7)
Source: JAMA 1991;266:2852-5
HBsAg-positive
No. (%)
Elimination of Hepatitis B Virus Transmission
United States
Strategy
• Prevent perinatal HBV transmission
(1984 - selective; 1988 – universal)
• Routine infant vaccination (1991)
• Catch-up vaccination
• 11-12 year-old children (1995)
• All children <19 years of age (1997)
• Adults in high risk groups (1982)
Coverage, %
HepB3, DTP3, and Hib3 Coverage,
Among 19-35 Month-Old Children, 1992-2000
100
90
80
70
60
50
40
30
20
10
0
DTP3
Routine
HepB vaccination
recommended
Hib3
HepB3
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000
Year
Reported Cases of Acute Hepatitis B in Children
United States, 1985-2000
Reported Cases
200
150
100
50
Routine
HepB vaccination
recommended
5-9 years
1-4 years
0
1985
1987
1989
1991 1993
Year
1995
1997
1999
Estimated Non-Perinatal HBV Infections
Among Children <10 Years of Age
United States, 1991
Incidence
Per 100,000
(95% CI)
Annual
Infections,
No. (95% CI)
36.6
24
(9-62)
8,680
(3,310-22,770)
Asian
1.2
605
(471-783)
7,280
(5,670-9,420)
Total
37.8
42
(24-85)
15,950
(8,980-32,190)
Racial/Ethnic
Group
Non-Asian
Population
(millions)
Source: Armstrong, et al. Pediatrics 2001; in press
Age of Acquisition for Persons with
Chronic HBV Infection, United States
Newborn, 18%
Children, 18%
Adult, 59%
Adolescent, 6%
Elimination of Hepatitis B Virus Transmission
United States
Strategy
• Prevent perinatal HBV transmission
(1984 - selective; 1988 – universal)
• Routine infant vaccination (1991)
• Catch-up vaccination
• 11-12 year-old children (1995)
• All children <19 years of age (1997)
• Adults in high risk groups (1982)
Percent Coverage
National vaccination coverage levels of adolescents
13-15 years of age, NHIS
100
90
80
70
60
50
40
30
20
10
0
93 92
89 91
60
48
3+ Hep B
1997
1998
45 45
2+ MMR
1+ Varicella
1+ Td
States Requiring Hepatitis B Vaccination
Before Middle School Entry, 2001
WASHINGTON
MONTANA
MAINE
NORTH
DAKOTA
MINNESOTA
OREGON
VT
NH
WISCONSIN
IDAHO
SOUTH
MICHIGAN
WYOMING
MA
NEW
YORK
DAKOTA
CT
RI
IOWA
NEVADA
PENNSYLVANIA
NEBRASKA
NJ
OHIO
IN
UTAH
DE
ILLINOIS
DC
COLORADO
WV
KANSAS
VIRGINIA
MISSOURI
KENTUCKY
CALIFORNIA
NO.
31 of 50 States
have HepB
immunization
requirements
CAROLINA
TENNESSEE
OKLAHOMA
ARIZONA
NEW
MEXICO
SO.
ARKANSAS
CAROLINA
MS
GEORGIA
ALABAMA
TEXAS
LA
ALASKA
FL
HAWAII
MD
Reported cases of acute hepatitis B among 15-18 year olds
United States, 1990-2000
20
Total
15
Monovalent HepB
10
Hib-HepB
5
0.4%
8.5% 14.6% 18.3%
00
20
99
19
98
19
97
19
96
19
95
19
94
19
93
19
92
19
91
19
90
0
19
Millions of doses
Hepatitis B vaccine doses
distributed in public sector
United States, 1990-2000
Thimerosal: Changes in Hepatitis B Vaccine
Recommendations, July 1999
Joint PHS-AAP Statement
“Clinicians and parents can take advantage of
the flexibility within the existing
schedule…to postpone the first dose of
hepatitis B vaccine from birth until 2 to 6
months of age…”
AAP
“If thimerosol-free vaccine is not available,
hepatitis B virus vaccination should be
initiated at 6 months of age”
HepB Doses Administered Before Age 2 Months
Oregon Immunization Registry, 2/99 – 3/00
Doses Administered
1200
Joint Statement
1000
800
600
400
200
Hep B given
0-56 days after birth
Preservative-free
HepB available
through VFC
Preservative-free
HepB available
in hospitals
Hep B given
0-5 days after birth
0
1999
Week
Source: Oregon Immunization ALERT registry
2000
Vaccine coverage among infants born to
unscreened women, Oregon, 1999-2000
100
80
HepB received
<12 hours after
birth
60
40
20
HepB received
before discharge
0
Apr-Jun
Aug-Oct
Apr-Jun
1999
1999
2000
July 11, 1999: CDC/AAP announcement to defer vaccination of infants born to HBsAg neg women
No change in recs for unscreened women
August 28, 1999: Resume previous policies
Why Should Birth Dose Be Given to All Infants?
• “Safety net” – If all get birth dose, eliminates missed
immunoprophylaxis for infants born to HBsAg-positive
mothers (a medical error)
• Assures immunoprophylaxis for infants born to
unscreened women (10x more likely to be HBsAgpositive)
• May reduce number of doses that need to be given
simultaneously with other vaccines
• May increase likelihood that the Hep B series will be
given on schedule
• Conveys the importance of vaccination to parents
Hepatitis B Combination Vaccines
Concerns
• Requires use of 4 dose schedule to prevent perinatal
HBV transmission
– Potential to decrease use of birth dose
– Increased cost/cost-effectiveness data?
– Safety data?
• Need to assure adequate immunogenicity of all vaccine
components in schedules used in developed and
developing countries (w/ and w/o birth dose)
• Increased vaccine cost per dose
– requires increased attention to vaccine wastage
– smaller vaccine vials – increased need for cold chain
capacity
• Could displace local DTP production