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ACIP BRIEFING MATERIALS FOR PUBLIC POSTING
The Non -specific Effects of Hepatitis B Vaccines : A Rapid Systematic Revie w
Table of Contents
A. Background ................................ ................................ ................................ ................................ ................................ ..... 3
B. Methods ................................ ................................ ................................ ................................ ................................ .......... 3
B.1. Key Question Development ................................ ................................ ................................ ................................ ..... 3
B.2. Literature Search ................................ ................................ ................................ ................................ ...................... 3
B.3. Study Selection ................................ ................................ ................................ ................................ ......................... 4
B.4. Data Extraction, Study Assessment, and Synthesis ................................ ................................ ................................ . 6
B.5. GRADE -ing and Recommendation Development ................................ ................................ ................................ .... 6
C. Summary of Evidence ................................ ................................ ................................ ................................ ..................... 7
C.1. Evidence Tables ................................ ................................ ................................ ................................ ........................ 7
C.1.a. GRADE -ed Summary of Findings ................................ ................................ ................................ ........................... 7
D. Extracted Evidence from Included Studies ................................ ................................ ................................ ............... 14
E. Search Strategies and Results ................................ ................................ ................................ ................................ .......... 21
F. References ................................ ................................ ................................ ................................ ................................ ........ 23
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Table 1. PI/ECO(ST) Criteria for Key Question ................................ ................................ ................................ ....................... 3
Table 2. GRADE Table: Mortality and administration of monovalent hepatitis B vaccines in the first 6 years of life ....... 7
Table 3. GRADE Table: Mortality and administration of all hepatitis B -containing vaccines in the first 6 years of life ... 10
Table 4. GRADE Table: Cardiopulmonary outcomes and administration of hepatitis B vaccines in the first 6 years of life
................................ ................................ ................................ ................................ ................................ .............................. 14
Table 5. Characteristics of Studies Meeting Inclusion Criteria ................................ ................................ ........................... 14
Table 6. Results of Studies Meeting Inclusion Criteria ................................ ................................ ................................ ........ 15
Table 7. Risk of Bias Assessment of Studies Meeting Inclusion Criteria ................................ ................................ ............ 19
Table 8. Primary Search of MEDLINE (OVID), Embase (OVID), CINAHL (Ebsco), Scopus, Cochrane Library ...................... 21
Figure 1. Results of the Study Selection Process ................................ ................................ ................................ ................... 5
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A. Background
Non -specific effects of vaccination include broader impacts that may be conferred by vaccines beyond protection against
their target pathogen, including the potential for effects on all -cause morbidity and mortality, non -targeted infections,
allergic and a topic disease, autoimmune and immune -mediated disease, and malignancy.1 While the non -specific effects
of certain vaccines, including Bacille Calmette -Guérin (BCG) vaccine, measles -containing vaccines, and diphtheria -
tetanus -pertussis vaccines, among others,1 have been previously studied, an evidence -based review of non-specific
effects associated with hepatitis B -containing vaccines is needed. Given the need to ensure the safety of all vaccination s
administered in childhood, we propose a systematic review of the literature to understand any non -specific effects of
childhood vaccinations. In this report, we focused on the literature that evaluated non -specific effects of hepatitis B
vaccination .
B. Methods
B.1. Key Question Development
The Key Question was developed by infectious disease and systematic review methodology subject matter experts
using the PICO framework2 (Population, Intervention, Comparator, and Outcome ). The Key Question and PI /ECO(ST)
Criteria used to guide the literature review are:
1. What are the non -specific effects of childhood vaccines?
Table 1. PI/ECO(ST) Criteria for Key Question
PI/ECO(ST) ELEMENT Description for this Review
Population Infants and children through 6 years of age
Intervention or
Exposure Hepatitis A (HAV) – Havrix, VAQTA, Hepatitis B (HBV) – Recombivax HB, Engerix -B, Rotavirus
– ROTARIX, RotaTeq, Diphtheria, tetanus, acellular pertussis (DTaP) – Infanrix, Daptacel,
Haemophilus influenzae type B (Hib) – PedvaxHIB, ActHIB, Hiberix, Poliomyel itis/polio (IPV) –
IPOL, Pneumococcal (PCV15, PCV20) –VAXNEUVANCE, Prevnar 20, Measles, mumps rubella
(MMR) – PRIORIX, M -M-R II, Varicella - Varivax
RSV – Nirsevimab, Clesrovimab, Combination vaccines – Pediarix, Kinrix, Quadracel, Vaxelis,
Pentacel, ProQuad
Comparator (if
applicable) Any or none
Outcome(s) Non -specific effects, all -cause morbidity, all -cause mortality (death), non -targeted infection
(sepsis, respiratory tract), allergic and atopic disease (asthma, eczema, atopic dermatitis,
food allergy), autoimmune and immune -mediated disease (type 1 diabet es mellitus,
inflammatory bowel disease – ulcerative colitis and Crohn’s disease, juvenile idiopathic
arthritis, systemic lupus erythematosus, Hashimoto’s thyroiditis, alopecia), malignancy
(cancer, leukemia)
Setting Any
Time Frame Any publication years
Any duration of follow up
B.2. Literature Search
A CDC informationist (J T) developed search strategies from the Key Question s and PICO criteria, and performed the
search in MEDLINE, EMBASE , CINAHL , and Cochrane Library from the start of each database to August 20, 2025 .
Search strategies and results are provided in Table 8.
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B.3. Study Selection
Results of the literature searches were uploaded into EndNote 21 (Clarivate Analytics©, Thomson Reuters, New
York, NY, USA), duplicate records were removed, and unique t itles and abstracts were uploaded to Covidence
(Veritas Health Innovation Ltd., Melbourne, VIC, Australia) where a second round of deduplication was conducted.
As this was the first of several planned systematic reviews on non -specific effects of childhood vaccination, a
keyword search was conducted to filter records with title and abstracts relevant for hepatitis B vaccines (Hepatitis B,
HBV, HepB, Engerix -B, Recombivax HB, Pediarix, Vaxelis). Two reviewers (EQ, EM, BE ) independently screened all
titles and abstracts and removed irrelevant references. Relevant full texts were screened independent ly by two
reviewers (EQ, LZ ) and disagreements were resolved by consensus . All studies were screened according to the pre -
identified exclusion criteria below, and results of the study selection process are provided in Figure 1 .
Criteria for excluding studies from the literature review include:
1. No full text available;
2. Not available in English;
3. Not relevant to key question ;
4. No population of interest (study popula tion did not include children vaccinated at ≤6 years of age ;
5. No intervention of interest (no hepatitis B vaccine exposure) ;
6. No outcome of interest;
7. No primary data or secondary data not systematically collected (no reproducible methods) ; or
8. Insufficient me thodologic reporting (i.e., m eeting abstract or poster );
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Figure 1. Results of the Study Selection Process
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policy . Page 6 of 24
B.4. Data Extraction , Study Assessment , and Synthesis
Data from studies meeting inclusion criteria were independently extracted by two reviewers using a standardized Microsoft Excel (2021) form, and
differences were reconciled by discussion. Extracted data included study characteristics (Table 5). Outcome data were extracted as presented in the studies
or calculated using data provided. For the purposes of this review, statistical significance was defined as p ≤ 0.05 . The risk of bias for each study was assessed
according to study type using standardized risk of bias tools appropriate to the identified st udy type. Tools were modified to specify region, time, age ,
weight, and prematurity, as confounding factors and to include an assessment of conflict -of-interest disclosures . The Newcastle -Ottawa Scale was used for
cohort and case control studies , R.O.B2. for randomized controlled trials (RCTs) , and JBI tools were used to assess the risk of bias for Case Series and
Systematic Reviews . The signaling questions used to assess study conduct and risk of bias and results are presented in Table 6. The evidence was narratively
synthesized for each outcome domain, and for specific outcomes where definitions aligned.
B.5. GRADE -ing and Recommendation Development
The Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach was used to assess the risk of bias , imprecision,
inconsistency, and indirectness , and final confidence for the body of evidence foreach outcome .3
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C. Summary of Evidence
C.1. Evidence Tables
C.1.a. GRADE -ed Summary of Findings
Key Question: Among children, what are the non-specific effects of hepatitis B vaccine s administered in the f irst 6 years of life ?
Table 2. GRADE Table: Mortality and administration of monovalent hepatitis B vaccines in the first 6 years of life
Outcome Summary Studies Risk of Bias Imprecision Inconsistency Indirectness Confidence
All Mortality
Outcomes,
Monovalent
Hepatitis B
Vaccines Evidence from 3 cohorts suggests hepatitis B vaccine
administration may not be associated with an increase
in risk of mortality in high -income countries ( HIC) and
may be associated with an increase in risk in low-and
middle -income countries ( LMIC ). Two studies from HIC
suggest either a protective or no effect of hepatitis B
vaccination on mortality and one study from an LMIC
suggest s an increase in mortality after hepatitis B
vaccination . Evidence from 1 cohort and 1 nested case
series is inconsistent about sex-specific mortality after
receipt of hepatitis B vaccines; one study suggest s both
no difference and an increase in the female -to-male
mortality ratio and one study sugges ts no difference in
mortality by sex. One cohort suggest s either a protective
or no effect on hepatitis B vaccines and cancer -related
and cardiovascular -related mortality. 4 Studies
(N=46,628) Some concernsa No concerns No concernsb Some
concernsc Very low
confidence
Mortality Summary: The evidence from 2 cohort studies (He 2022
and Morgan 2025) in HIC suggests no association or a
decrease in mortality after hepatitis B vaccination. The
evidence from 1 cohort in Guinea -Bissau (Garly 2004)
suggests an increase in mortality after hepatitis B
vaccination; these findings had some concerns for bias. 3 Cohorts
(He 2022,
Morgan
2025, Garly
2004)
(N=46,515) Some concernsd No concerns No concernse Some
concernsf Very low
confidence
a Confounding by weight/ weight -for-age z score or health service utilization in 2 studies, temporal variation in 2 studies, regional differences in 2 studies, concern for exposure
misclassification in 1 study and inadequate follow up in 1 stud y.
b Inconsistency may be explained by direct and indirect population differences .
c Aaby 2006 and Garly 2004 are conducted in LMIC population s.
d Confounding by weight/weight -for-age z score or health service utilization in 2 studies, temporal variation in 2 studies, regional differences in 2 studies, and inadequate follow
up in 1 stud y.
e Inconsistency may be explained by direct and indirect population differences .
f Garly 2004 is conducted in a LMIC population .
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Outcome Summary Studies Risk of Bias Imprecision Inconsistency Indirectness Confidence
• One cohort (He, 2022) of 36,791 participants in
the National Health and Nutrition Examination
Survey in the United States suggested a
reduced risk of all -cause mortality associated
with hepatitis B vaccination [aHR 0.78 (95%CI:
0.68 -0.90); 390/10,785 PY vs 4,185/26,006 PY]
following vaccination prior to 1.5 years of age
with a median follow -up of 8 years .
• One cohort (Morgan 2025) of extremely
preterm infants (<29 weeks gestation) in
Australia’s Surveillance of Adverse Events
Following Immunization in the Community
suggested there is no difference in risk of death
during the first 3 months of life when
compa ring infants with a record of receiving
hepatitis b vaccine within 24 hours of birth to
infants with no record of receiving hepatitis B
vaccine within 24 hours of life [aRR: 1.13;
(95%CI: 0.42 -2.81); 7/306 vs 14/512].
• One cohort study (Garly 2004) of 8,906 children
from Bandim Health Project's Health and
Demographic Surveillance System in Guinea -
Bissau suggested increased mortality rate at 7 ½
- 12 months of age compared to mortality rate
at 1 ½ - 7 ½ months of age [aMR R: 1.62, 95% CI:
1.09, 2.41) for the birth cohort in which most
children received hepatitis B vaccination
(Hepaccine) at 7 ½ months of age. In a
subgroup analysis within a measles vaccine
(MV) trial , mortality rate for children 7 ½ -12
months of age was ele vated among those
receiving hepatitis B vaccine (+MV) compared
to hepatitis B -unvaccinated (+MV) children
(5,441 children), [MRR 1.81 (95%CI: 1.19 -2.75)].
Hepaccine is not approved for use in the United
States.
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policy . Page 9 of 24
Outcome Summary Studies Risk of Bias Imprecision Inconsistency Indirectness Confidence
Female and male
mortality One cohort (Garly 2004) from Bandim Health Project's
Health and Demographic Surveillance System in Guinea -
Bissau suggested elevated female -to-male (F/M)
mortality in a subgroup of 5,061 children ages, evaluated
through 12 and 24 months within a 2 -dose mea sles trial,
among those vaccinated for hepatitis B ( Hepaccine) 12
months: [F/M MRR 1.66 (95%CI: 0.80 -3.45); 18/143.8 PY
vs 12/159.1 PY] 24 months: [F/M MRR 2.20 (95%CI: 1.07 -
4.54); 22/358 PY vs 11/394.3 PY].
In a nested case series (Aaby 2006) in The Gambia’s
Medical Research Council Laboratories’ Demographic
Surveillance System, hepatitis B vaccine was the last
vaccination received among 7% (4/60) of female infants
and 0% (0/53) male infants who died and had vaccination
status available from 2 -17 months of age . 1 Cohort
(Garly 2004)
(N= 8,906)
1 Case
series
(Aaby 2006)
(N=113) Some concernsg No concerns No concerns Some
concernsh Very l ow
confidence
Cancer -related
mortality One cohort (He 2022) of 36,791 participants in the United
States’ National Health and Nutrition Examination Survey
suggested a trend toward reduction in cancer -related
mortality among people 6 years and older who had
received a hepatitis B vaccine compared to those who
were unvaccinated for hepatitis B [aHR 0.76 (95%CI: 0.58 -
1.00 ); 97/10,785 PY vs 881/26,006 PY ]. Most of the
vaccinated population had received hepatitis B vaccine in
the first 1.5 years of life with a median follow -up of 8
years .
1 Cohort
(He 2022)
(N=36,791) No concerns No concerns No concerns No concerns Low confidence
Cardiovascular -
related mortality One cohort (He 2022) of 36,791 participants in the United
States’ National Health and Nutrition Examination Survey
suggested no association between cancer -related
mortality in people 6 years and older and hepatitis B
vaccination [aHR 0.83 (95%CI: 0.60 -1.15 ); 53/10,785 PY vs
732/26,006 PY ]. Most of the vaccinated population had
received hepatitis B vaccine in the first 1.5 years of life
with a median follow -up of 8 years .
1 Cohort
(He 2022)
(N=36,791)
No concerns No concerns No concerns No concerns Low confidence
g Confounding by weight/weight -for-age z score or health service utilization and concern for exposure misclassification in 1 study .
h Conducted in LMIC population .
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Table 3. GRADE Table: Mor tality and administration of all hepatitis B -containing vaccines in the first 6 years of life
Outcome Summary Studies Risk of Bias Imprecision Inconsistency Indirectness Confidence
All mortality
outcomes, all
hepatitis B -
containing vaccines Evidence from 4 cohorts is inconclusive about whether
receipt of a hepatitis B -containing vaccine is associated
with mortality . Studies (n=2) from HIC suggest a
protective or no effect of hepatitis B vaccination on
mortality and studies (n=2) from LMIC suggest an
increase in mortality after hepatitis B vaccination.
Evidence from 4 cohorts and 1 nested case series about
sex-specific mortality after hepatitis B -containing
vaccines varies . One cohort suggested either a
protective or no effect of hepatitis -B co ntaining vaccines
on cancer -related and cardiovascular -related mortality.
Findings may differ due to differences in types of
vaccines administered. Some studies evaluated
monovalent hepatitis -B vaccines , and some studies
evaluated pentavalent vaccines, which contain antigens
to protect against diphtheria, tetanus, pertussis,
haemophilus influenzae type B and hepatitis B. 8 Studies
(N=82,849) Some
concernsi No concerns No concernsj Some concernsk Very low
confidence
Mortality Summary: The evidence from 2 cohort studies (He 2022
and Morgan 2025) in HIC suggests no increase in the risk
of mortality with hepatitis -B vaccination at a follow up of
3 months of life and a median follow up of 8 years of life .
• One cohort (He, 2022) of 36,791 participants in
the United States’ National Health and
Nutrition Examination Survey suggested a
reduced risk of all -cause mortality associated
with hepatitis B vaccination [aHR 0.78 (95%CI: 4 Cohorts
(He 2022,
Morgan
2025, Fisker
2018, Garly
2004)
(N=53,609) Some concernsl No concerns No concernsm Some concernsn Very low
confidence
i Confounding by weight/weight -for-age z score or health service utilization in 4 studies, temporal variation in 3 studies, regional differences in 2 studies, concern for exposure
misclassification in 1 study , outcome misclassification in 2 studies and inadequate follow up in 1 stud y.
j Inconsistency may be explained by direct and indirect population differences
k Aamand 2023, Hanifi 2021, Fisker 2018, Fisker 2016, Aaby 2006, Garly 2004 are conducted in a LMIC population
l Confounding by weight/weight -for-age z score or health service utilization in 3 studies, age at administration in 1 study, temporal variation in 2 studies, regional differences in 2
studies, concern for outcome misclassification in 1 study and inadequate follow up in 1 stud y.
m Inconsistency may be explained by direct and indirect population differences
n Fisker 2018 and Garly 2004 are conducted in a LMIC population
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Outcome Summary Studies Risk of Bias Imprecision Inconsistency Indirectness Confidence
0.68 -0.90); 390/10,785 PY vs 4,185/26,006 PY]
following vaccination prior to 1.5 years of age
with a median follow -up of 8 years .
• One cohort (Morgan 2025) of extremely
preterm infants (<29 weeks gestation) in
Australia’s Surveillance of Adverse Events
Following Immunization in the Community
suggested there is no difference in risk of death
during the first 3 months of life when
compa ring infants with a record of receiving
hepatitis b vaccine within 24 hours of birth to
infants with no record of receiving hepatitis B
vaccine within 24 hours of life [aRR: 1.13;
(95%CI: 0.42 -2.81); 7/306 vs 14/512].
Indirect evidence from 2 cohort studies in Guinea -Bissau
(Fisker 2018, Garly 2004) suggests there may be an
increase in the risk of mortality after hepatitis -B
containing vaccination (pentavalent and hepatitis B
vaccine ). There are concerns about the generalizability of
LMIC infant mortality data to HIC infants.
• In on e cohort (Fisker 2018) in Guinea -Bissau,
pentavalent vaccine is administered at a
younger age than measles vaccine. 7,094
infants in Bandim Health Project's Health and
Demographic Surveillance System suggested no
association between receiving a measles
vaccine first and then a pentavalent vaccine
[aHR 1.19 (95%CI: 0.84 -1.69); 43/2,847 PY vs
160/14,186 PY], receiving missing pentavalent
doses [aHR 1.87 (95%CI: 0.96 -3.65); 10/430 PY
vs 160/14,186 PY] or not receiving missing
pentavalent doses [aHR 0.93 (95%CI: 0.57 -
1.54); 17/1,537 PY vs 160/14,186 PY] compared
to receipt of a pentavalent vaccine first and
then a measles vaccine.
• One cohort study (Garly 2004) of 8,906 children
from Bandim Health Project's Health and
Demographic Surveillance System in Guinea -
Bissau suggested increased mortality rate at 7
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Outcome Summary Studies Risk of Bias Imprecision Inconsistency Indirectness Confidence
½ - 12 months of age compared to mortality
rate at 1 ½ - 7 ½ months of age [aMRR: 1.62,
95% CI: 1.09, 2.41) for the birth cohort in which
most children received hepatitis B vaccination
(Hepaccine) at 7 ½ months of age. In a
subgroup analysis within a measles vaccine
(MV) trial , mortality rate for children 7 ½ -12
months of age was elevated among those
receiving hepatitis B vaccine (+MV) compared
to hepatitis B -unvaccinated (+MV) children
(5,441 children), [MRR 1.81 (95%CI: 1.19 -2.75)].
Hepaccine is not appro ved for use in the United
States.
Female -to-male
mortality Summary: Indirect evidence from 4 cohort studies in
LMIC suggests there may be an increase in risk of
mortality among female compared to male children
receiving hepatitis B vaccines. An increased female -to
male mortality rate was observed in 2 cohorts (Hanifi
2021, Fisker 2016) but not in 1 cohort (Aamand 2023).
One cohort in LMIC reported no difference in female to
male mortality at 12 months of age and an increase in
female mortality at 24 months (Garly 2004).
• One cohort (Aamand 2023) of 12,753 infants in
Bandim Health Project's Health and
Demographic Surveillance System in Guinea -
Bissau suggested no association between
female and male mortality and pentavalent
vaccination [F/M aMRR 1.01 (95%CI: 0.82 -1.25);
73/2,901 PY vs 78/2,930 PY )] through 6 months
of follow -up post -vaccination .
• One cohort (Hanifi 2021) of 7,644 children ages
6 weeks - 9 months in the International Center
for Diarrheal Diseases Research Bangladesh’s 4 Cohorts
(Aamand
2023, Hanifi
2021, Fisker
2016, Garly
2004)
(N=38,033)
1 Case series
(Aaby 2006)
(N=113)
Some
concernso Some concernsp No concerns Some concernsq Very low
confidence
o Confounding by weight/weight -for-age z score or health service utilization in 2 studies and concern for exposure misclassification in 1 study and outcome misclassification in 1
study .
p Wide confidence intervals in the study reporting the highest female to male mortality differences .
q Conducted in LMIC population s.
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Outcome Summary Studies Risk of Bias Imprecision Inconsistency Indirectness Confidence
Health and Demographic Surveillance System
suggested elevated female -to-male mortality
after pentavalent vaccination [F/M MRR 9.91
(95%CI: 1.16 -84.44)].
• One cohort (Fisker 2016) of 8,730 infants in
Bandim Health Project's Health and
Demographic Surveillance System in Guinea -
Bissau suggested elevated female -to-male
mortality after pentavalent vaccination [F/M
aMRR 1.86 (95%CI: 1.16 -2.98), 52/1,939 PY vs
31/1,999 PY] through 6 -months post -
vaccination .
• One cohort (Garly 2004) from Bandim Health
Project's Health and Demographic Surveillance
System in Guinea -Bissau suggested no
difference in F/M mortality at 12 months [F/M
MRR 1.66 (95%CI: 0.80 -3.45); 18/143.8 PY vs
12/159.1 PY] and elevated F/M mortality at 24
months [F/M MRR 2.20 (95%CI: 1.07 -4.54);
22/358 PY vs 11/394.3 PY]. after hepatitis B
vaccination ( Hepaccine) in a subgroup of 5,061
children In a nested case series (Aaby 2006) in
The Gambia’s Medical Research Council
Laboratories’ Demographic Surv eillance
System, hepatitis B vaccine was the last
vaccination received by 7% (4/60) of female
infants and 0% (0/53) male infants who died
and had vaccination status information
available .
Cancer -related
mortality One cohort (He 2022) of 36,791 participants in the United
States’ National Health and Nutrition Examination Survey
suggested a trend toward a reduction in cancer -related
mortality among people 6 years and older who had
received a hepatitis B vaccin e compared to those who
were unvaccinated for hepatitis B [aHR 0. 76 (95%CI: 0. 58-
1.00 ]. Most of the vaccinated population had received
hepatitis B vaccine in the first 1.5 years of life with a
median follow -up of 8 years.
1 Cohort
(He 2022 )
(N=36,791)
No concerns No concerns No concern No concerns Low
confidence
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Outcome Summary Studies Risk of Bias Imprecision Inconsistency Indirectness Confidence
Cardiovascular -
related mortality One cohort (He 2022) of 36,791 participants in the
United States’ National Health and Nutrition Examination
Survey suggested no association between cancer -related
mortality in people 6 years and older and hepatitis B
vaccination [aHR 0.83 (95%CI: 0.60 -1.15] . Most of the
vaccinated population had received hepatitis B vaccine in
the first 1.5 years of life with a median follow -up of 8
years .
1 Cohort
(He 2022 )
(N=36,791)
No concerns No concerns No concerns No concern s Low
confidence
Table 4. GRADE Table: Cardiopulmonary outcomes and administration of hepatitis B vaccines in the first 6 years of life
Outcome Summary Studies Risk of Bias Imprecision Inconsistency Indirectness Confidence
Cardiopulmonary The evidence from 1 cohort suggests that receipt of hepatitis
B vaccine in the first 24 hours of life is not associated with an
increase in the risk of bronchopulmonary dysplasia. 1 Stud y
(N=818) Som e
concerns No concerns
No concerns
No concerns
Low
confidence
Bronchopulmonary
dysplasia One cohort (Morgan 2025) of extremely preterm infants (<29
weeks gestation) in Australia’s Surveillance of Adverse Events
Following Immunization in the Community suggested there is a
reduction in risk of bronchopulmonary dysplasia when
comparing preterm infants with a record of receiving hepatitis
b vaccine within 24 hours of birth to preterm infants with no
record of hepatitis B vaccine within 24 hours of birth [aRR:
0.83; (95%CI: 0.68 -1.0); 155/306 vs 317/512].
1 Cohort
(Morgan
2025 N =
818) No concerns No concerns No concerns No concerns Low
confidence
D. Extracted Evidence from Included Studies
Table 5. Characteristics of Studies Meeting Inclusion Criteria
Author
Year Study
design Data Collection
Period Vaccine Sample size, N Surveillance System (if Applicable) Country
Aaby 20064 Nested case
series 1998 -2002 Hepatitis B [unspecified
manufacturer] 113 children who had died and
had vaccination status Medical Research Council Laboratories'
Demographic Surveillance System in Farafenni The Gambia
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policy . Page 15 of 24
Author
Year Study
design Data Collection
Period Vaccine Sample size, N Surveillance System (if Applicable) Country
Aamand
20235 Cohort September 1, 2008 –
December 31, 2017 Pentavalent * 12,753 children Bandim Health Project's Health and
Demographic Surveillance System Guinea -Bissau
Fisker
20166 Cohort September 1, 2008 –
April 18, 2011 Pentavalent * 8,730 children Bandim Health Project's Health and
Demographic Surveillance System Guinea -Bissau
Fisker
20187 Cohort September 1, 2008 –
June 22, 2015 Pentavalent * 7,094 children
Bandim Health Project's Health and
Demographic Surveillance System Guinea -Bissau
Garly 20048 Cohort March 1994 – February
2000 Hepatitis B (Hepaccine) 8,906 children Bandim Health Project's Health and
Demographic Surveillance System Guinea -Bissau
Hanifi
20219 Cohort June 29, 2011 – April
20, 2016 Pentavalent * 7,644 children International Center for Diarrheal Diseases
Research Bangladesh's Health and Demographic
Surveillance System in Chakaria Bangladesh
He 202210 Cohort 1999 – 2018 Hepatitis B [Unspecified
manufacturer,
thimerosal -free] 36,791 participants National Health and Nutrition Examination
Survey United States
Morgan
202511 Cohort January 1, 2017 –
December 31, 2020 Hepatitis B [Engerix -B
or HB -Vax-II,
thimerosal -free] 818 extremely preterm infants Surveillance of Adverse Events Following
Immunization in the Community Australia
*Pentavalent vaccine : Diphtheria -Tetanus -whole cell Pertussis -Hemophilus influenzae type B -Hepatitis B
Table 6. Results of Studies Meeting Inclusion Criteria
Study Study
Type Exposure Outcome Follow -up Outcome
Identification Intervention
% or rate
(n/N or
person -time ) Control % or
rate (n/N or
person -time) p-
value Measure of
Association
(95% CI) Adjusted Risk of
Bias
Aaby 2006 Nested
case
series Hepatitis B as
last vaccin e Female d eath s Vaccination
through 18
months of age Verbal autopsy 7% (4/60) NA NA NA No High risk
of bias
Aaby 2006 Nested
case
series Hepatitis B as
last vaccine Male deaths Vaccination
through 18
months of age Verbal autopsy 0% (0/53) NA NA NA No High risk
of bias
Disclaimer: The findings and conclusions herein are draft and have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or
policy . Page 16 of 24
Study Study
Type Exposure Outcome Follow -up Outcome
Identification Intervention
% or rate
(n/N or
person -time ) Control % or
rate (n/N or
person -time) p-
value Measure of
Association
(95% CI) Adjusted Risk of
Bias
Aamand
2023 Cohort Pentavalent
vaccination Female/male
mortality Vaccination
through 6
months post -
vaccination Reported
cause of death 25.5 per 1,000
person -years
(73/2,901 PY) 26.6 per 1,000
person -years
(78/2,930 PY) NR 1.01 (0.82 -
1.25) Yes Low risk of
bias
Fisker 2016 Cohort Pentavalent
vaccination Female/male
mortality Vaccination
through either
Subsequent
vaccination
contact or 6
months post -
vaccination Verbal
autopsy,
medical review 26.8 per 1,000
PY (52/1,939
PY) 15.5 per 1,000
PY (31/1,999
PY) 0.01 1.86 (1.16-
2.98) Yes Moderate
risk of bias
Fisker 2018 Cohort Pentavalent
after measles
vaccine Mortality First home visit
after 9 months
to 5 years of
age Interview 15.1 per 1,000
PY (43/2,847
PY) 11.3 per 1,000
PY (160/14,186
PY) NR 1.19 (0.84 -
1.69) Yes High risk
of bias
Fisker 2018 Cohort Received
missing
Pentavalent
vaccine at
most recent
visit Mortality First home visit
after 9 months
to 5 years of
age Interview 23.3 per 1,000
PY (10/430 PY) 11.3 per 1,000
PY (160/14,186
PY) NR 1.87 (0.96 -
3.65) Yes High risk
of bias
Fisker 2018 Cohort Did not
receive
missing
pentavalent
vaccine at
most recent
visit Mortality First home visit
after 9 months
to 5 years of
age Interview 11.1 per 1,000
PY (17/1 ,537
PY) 11.3 per 1,000
PY (160/14,186
PY) NR 0.93 (0.57 -
1.54) Yes High risk
of bias
Garly 2004 Cohort 7 ½ - 12 vs 1 ½
- 7 ½ months
of age, cohort
receiving
hepatitis B
vaccine
(Hep accine) Mortality 1.5 months
through 12
months of age Death
registration
system
NR NR 0.03
1.62 (1.09 -
2.41)
Yes Moderate
risk of bias
Disclaimer: The findings and conclusions herein are draft and have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or
policy . Page 17 of 24
Study Study
Type Exposure Outcome Follow -up Outcome
Identification Intervention
% or rate
(n/N or
person -time ) Control % or
rate (n/N or
person -time) p-
value Measure of
Association
(95% CI) Adjusted Risk of
Bias
Garly 2004 Cohort Hepatitis B
vaccination
(Hepaccine) Mortality 1.5 months
through 12
months of age Death
registration
system
nr/876 nr/4565 NR 1.81 (1.19 -
2.75) No Moderate
risk of bias
Garly 2004 Cohort Hepatitis B
(Hepaccine) +
measles
vaccine vs
measles
vaccine Female/male
mortality 7 ½ months
through 12
months of age Death
registration
system 12.5%
(18/143.8 PY) 7.5% (12/159.1
PY) NR 1.66 (0.80 -
3.45) No Moderate
risk of bias
Garly 2004 Cohort Hepatitis B
(Hepaccine) +
measles
vaccine vs
measles
vaccine Female/male
mortality 9 months
through 24
months of age Death
registration
system
6.1% (22/358
PY) 2.8% (11/394.3
PY) 0.04 2.20 (1.07 -
4.54) No Moderate
risk of bias
Hanifi 2021 Cohort Pentavalent
vaccination Female/male
mortality 6 weeks
through 9
months of age Household
visit 14.3 per 1,000
PY (9/618 PY) 1.4 (1/667 PY) 0.01 9.91 (1.16 -
84.44) Yes High risk
of bias
He 2022 Cohort Hepatitis B
vaccination
[Unspecified
manufacturer,
thimerosal
free All-cause mortality Median follow -
up of 8 years NHANES
Linked
Mortality File ,
1999 -2018 2.8%
(390/10,785) 11.8%
(4,185/26,006) NR 0.78 (0.68 -
0.90) Yes Low risk of
bias
He 2022 Cohort Hepatitis B
vaccination
[Unspecified
manufacturer,
thimerosal
free Cancer -related
mortality Median follow -
up of 8 years
NHANES
Linked
Mortality File
1999 -2018
0.7%
(97/10,785) 2.6%
(881/26,006)
NR 0.76 (0.58 -
1.00) Yes Low risk of
bias
He 2022 Cohort Hepatitis B
vaccination
[Unspecified
manufacturer, Cardiovascular -
related mortality Median follow -
up of 8 years
NHANES
Linked
Mortality File ,
1999 -2018
0.4%
(53/10,785) 1.9%
(732/26,006) NR 0.83 (0.60 -
1.15) Yes Low risk of
bias
Disclaimer: The findings and conclusions herein are draft and have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or
policy . Page 18 of 24
Study Study
Type Exposure Outcome Follow -up Outcome
Identification Intervention
% or rate
(n/N or
person -time ) Control % or
rate (n/N or
person -time) p-
value Measure of
Association
(95% CI) Adjusted Risk of
Bias
thimerosal
free]
Morgan
2025 Cohort Hepatitis B
vaccine within
24 hours of
birth (Engerix -
B and H -B-Vax
II, thimerosal -
free) All-cause mortality Birth to 3
months Victorian
Deaths Index
data set 2.3%
(7/306 ) 2.7%
(14/512 ) 0.87 1.13 (0.42 -
2.81) Yes Some
concerns
Morgan
2025 Cohort Hepatitis B
vaccine within
24 hours of
birth
(Engerix -B and
H-B-Vax II,
thimerosal -
free) Bronchopulmonary
dysplasia Birth to 3
months ICD-10 50.7%
(155/306 ) 61.9%
(317/512 ) NR 0.83 (0.68 -
1.00) Yes Some
concerns
Disclaimer: The findings and conclusions herein are draft and have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or
policy . Page 19 of 24
Table 7. Risk of Bias Assessment of Cohort Studies Meeting Inclusion Criteria
STUDY NAME Aamand 2023 Fisker 2016 Fisker 2018 Hanifi 2021 He 2022 Garly 2004 Morgan 2025
SIGNALING QUESTION Cohort Cohort Cohort Cohort Cohort Cohort Cohort
Selection
Were the groups similar and recruited from the same population? Yes Yes Yes Yes Yes Yes Yes
Were exposures/ interventions measured similarly to assign patients/
people? Yes Yes Yes Yes Yes Yes Yes
Was the intervention/ exposure measured in a valid & reliable way? Yes Yes Yes Unclear Yes Yes Yes
Comparability/ Confounding
Comparability of groups on basis of design or analysis study controls/ adjusts for region study controls/ adjusts for region study controls/ adjusts for region study controls/ adjusts for region study controls/ adjusts for region study does not control/ adjust for region study does not control/ adjust for region
Comparability of groups on basis of design or analysis study controls/ adjusts for time period study does not control/ adjust for time period study controls/ adjusts for time period study controls/ adjusts for time period study does not control/ adjust for time period study controls/ adjusts for time period study does not control/ adjust for time period
Comparability of groups on basis of design or analysis study controls/ adjusts for weight study controls/ adjusts for weight study does not control/ adjust for weight study does not control/ adjust for weight study does not control/ adjust for weight study does not control/ adjust for weight study controls/ adjusts for weight
Comparability of groups on basis of design or analysis study does not control/ adjust for prematurity study does not control/ adjust for prematurity study does not control/ adjust for prematurity study does not control/ adjust for prematurity study does not control/ adjust for prematurity study does not control/ adjust for prematurity study controls/ adjusts for prematurity
Comparability of groups on basis of design or analysis study controls/ adjusts for age at administration study controls/ adjusts for age at administration study does not control/ adjust for age at administration study controls/ adjusts for age at administration study controls/ adjusts for age at administration study controls/ adjusts for age at administration study controls/ adjusts for age at administration
No residual confounding concerns exist Yes No No Unclear Yes No No
Outcome
Were the subjects free of the outcome of interest at the start of the
study? Yes Yes Yes Yes Yes Yes Yes
Were the outcomes measured in a valid and reliable way? Unclear Yes No No Yes Yes Yes
Was the same method of ascertainment or assessment of outcome
done for both groups? Yes Yes Yes Yes Yes Yes Yes
Was the non -response rate similar across both groups? Not applicable Not applicable Not applicable Not applicable Not applicable Unclear Not applicable
Follow up
Was the follow up time reported and long enough for outcomes to
occur? Yes Yes Yes Yes Yes Yes Unclear
Was follow up complete, and if not, were the reasons for loss to follow
up described and explored? Yes Yes Yes Unclear Yes Unclear Yes
Were strategies to address incomplete follow up utilized? Yes Yes Yes Yes Not applicable Yes Not applicable
Analysis
Were appropriate statistical analyses used? Yes Yes Yes Yes Yes Yes Yes
COI
Were conflicts of interest disclosed and no obvious conflicts exist? Yes Yes Yes Yes Yes No Yes
Risk -of-bias judgement Low risk of bias Some concerns High risk of bias High risk of bias Low risk of bias Some concerns Some concerns
Legend: Green = Yes or Possibly Yes, Yellow = Unclear, Red = No or Possibly No, Grey or Black = Not applicable
Disclaimer: The findings and conclusions herein are draft and have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or
policy . Page 20 of 24
Table 8. Risk of Bias Assessment of Case Series Studies Meeting Inclusion Criteria
STUDY NAME Aaby 2006
SIGNALING QUESTION Nested case series
Selection
Were there clear criteria for inclusion in the case series? Yes
Was the condition measured in a standard, reliable way for all
participants included in the case series? Possibly Yes
Were valid methods used for identification of the condition for
all participants included in the case series? Possibly No
Did the case series have consecutive inclusion of
participants? Yes
Did the case series have complete inclusion of participants? No Information
Was there clear reporting of the demographics of the
participants in the study? No
Was there clear reporting of clinical information of the
participants? No
Were the outcomes or follow up results of cases clearly
reported? No Information
Was there clear reporting of the presenting site(s)/clinic(s)
demographic information? No Information
Analysis
Were appropriate statistical analyses used? Yes
COI
Were conflicts of interest disclosed and no obvious conflicts
exist? Possibly Yes
Risk -of-bias judgement High risk of bias
Legend: Green = Yes or Possibly Yes, Yellow = Unclear, Red = No or Possibly No, Grey or Black = Not applicable
Disclaimer: The findings and conclusions herein are draft and have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or
policy . Page 21 of 24
E. Search Strategies and Results
Table 9. Primary Search of MEDLINE (OVID), Embase (OVID), CINAHL (Ebsco), Scopus, Cochrane Library
Search Strategy:
DATABASE STRATEGY RUN DATE RECORD
COUNT
Medline
(OVID)
1946 - 1. exp Hepatitis B Vaccines/
2. (((Hepatitis B OR HepB OR Hep B OR HBV) ADJ5 vaccin*) OR HepB -BD OR Engerix -B OR Recombivax HB).ti,ab,kf.
3. 1 OR 2
4. Exp Infant/
5. (Infant* OR newborn* OR new born* OR neonat* OR birth OR birth -dose*).ti,ab,kf.
6. 4 OR 5
7. Exp Safety/ OR exp Treatment Outcome/
8. (safety OR (vaccin* ADJ2 safe*) OR treatment outcome* OR adverse* OR harm OR harmful OR harms OR side effect* OR
reaction*).ti,ab,kf. OR ae.fs
9. 7 OR 8
10. Exp Clinical Study/ OR exp Product Surveillance, Postmarketing/
11. (trial* OR observational stud* OR observation stud* OR clinical stud* OR surveillance OR reporting system* OR VAERS OR
postmarket* OR post -market*).ti,ab,kf,hw.
12. 10 OR 11
13. 3 AND 6 AND 9 AND 12 07/31/2025 599
Embase
(OVID)
1947 - 1. exp Hepatitis B Vaccine/
2. (((Hepatitis B OR HepB OR Hep B OR HBV) ADJ5 vaccin*) OR HepB -BD OR Engerix -B OR Recombivax HB).ti,ab,kf.
3. 1 OR 2
4. Exp Infant/
5. (Infant* OR newborn* OR new born* OR neonat* OR birth OR birth -dose*).ti,ab,kf.
6. 4 OR 5
7. Exp Safety/ OR exp Treatment Outcome/ OR adverse drug reaction/
8. (safety OR (vaccin* ADJ2 safe*) OR treatment outcome* OR adverse* OR harm OR harmful OR harms OR side effect* OR
reaction*).ti,ab,kf. OR ae.fs
9. 7 OR 8
10. Exp Clinical Study/ OR exp Postmarketing Surveillance/
11. (trial* OR observational stud* OR observation stud* OR clinical stud* OR surveillance OR reporting system* OR VAERS OR
postmarket* OR post -market*).ti,ab,kf,hw.
12. 10 OR 11
13. 3 AND 6 AND 9 AND 12
14. limit 13 to "pubmed/medline"
15. 13 NOT 14
16. limit 15 to conference abstract status
17. 15 NOT 16 07/31/2025 1527
-
DUPLICATES
=165
UNIQUE
RECORDS
Disclaimer: The findings and conclusions herein are draft and have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or
policy . Page 22 of 24
DATABASE STRATEGY RUN DATE RECORD
COUNT
Cochrane
Library
#1 [mh "Hepatitis B Vaccines"]
#2 ((("Hepatitis B":ti,ab,kw OR HepB:ti,ab,kw OR "Hep B":ti,ab,kw OR HBV:ti,ab,kw) NEAR/5 vaccin*:ti,ab,kw) OR HepB -
BD:ti,ab,kw OR Engerix -B:ti,ab,kw OR "Recombivax HB":ti,ab,kw)
#3 #1 OR #2
#4 [mh Infant]
#5 (Infant*:ti,ab,kw OR newborn*:ti,ab,kw OR ("new" NEXT born*):ti,ab,kw OR neonat*:ti,ab,kw OR birth:ti,ab,kw OR birth -
dose*:ti,ab,kw)
#6 #4 OR #5
#7 [mh Safety] OR [mh "Treatment Outcome"]
#8 (safety:ti,ab,kw OR (vaccin*:ti,ab,kw NEAR/2 safe*:ti,ab,kw) OR ("treatment" NEXT outcome*):ti,ab,kw OR
adverse*:ti,ab,kw OR harm:ti,ab,kw OR harmful:ti,ab,kw OR harms:ti,ab,kw OR ("side" NEXT effect*):ti,ab,kw)
#9 #7 OR #8
#10 [mh ^"Clinical Study"] OR [mh ^"Product Surveillance, Postmarketing"]
#11 (trial*:ti,ab,kw OR ("observational" NEXT stud*):ti,ab,kw OR ("observation" NEXT stud*):ti,ab,kw OR ("clinical" NEXT
stud*):ti,ab,kw OR surveillance:ti,ab,kw OR ("reporting" NEXT system*):ti,ab,kw OR VAERS:ti,ab,kw OR
postmarket*:ti,ab,kw OR post -market*:t i,ab,kw)
#12 #10 OR #11
#13 #3 AND #6 AND #9 AND #12
07/31/2025 400
-
DUPLICATES
=145
UNIQUE
RECORDS
CINAHL
(EBSCOHost) S1 (MH "Hepatitis B Vaccines+")
S2 ((((TI "Hepatitis B" OR AB "Hepatitis B" OR SU "Hepatitis B") OR (TI HepB OR AB HepB OR SU HepB) OR (TI "Hep B" OR AB
"Hep B" OR SU "Hep B") OR (TI HBV OR AB HBV OR SU HBV)) N5 (TI vaccin* OR AB vaccin* OR SU vaccin*)) OR (TI HepB -BD
OR AB HepB -BD OR SU He pB-BD) OR (TI Engerix -B OR AB Engerix -B OR SU Engerix -B) OR (TI "Recombivax HB" OR AB
"Recombivax HB" OR SU "Recombivax HB"))
S3 S1 OR S2
S4 (MH Infant+)
S5 ((TI Infant* OR AB Infant* OR SU Infant*) OR (TI newborn* OR AB newborn* OR SU newborn*) OR (TI "new born*" OR AB
"new born*" OR SU "new born*") OR (TI neonat* OR AB neonat* OR SU neonat*) OR (TI birth OR AB birth OR SU birth) OR
(TI birth -dose* OR AB birt h-dose* OR SU birth -dose*))
S6 S4 OR S5
S7 (MH Safety+) OR (MH "Treatment Outcomes+") OR (MH "Adverse Drug Event+")
S8 ((TI safety OR AB safety OR SU safety) OR ((TI vaccin* OR AB vaccin* OR SU vaccin*) N2 (TI safe* OR AB safe* OR SU safe*))
OR (TI "treatment outcome*" OR AB "treatment outcome*" OR SU "treatment outcome*") OR (TI adverse* OR AB
adverse* OR SU adverse*) OR (TI harm OR AB harm OR SU harm) OR (TI harmful OR AB harmful OR SU harmful) OR (TI
harms OR AB harms OR SU harms) OR (TI "side effect*" OR AB "side effect*" OR SU "side effect*"))
S9 S7 OR S8
S10 (MH "Clinical Study+") OR (MH "Product Surveillance, Postmarketing+")
S11 ((TI trial* OR AB trial* OR SU trial*) OR (TI "observational stud*" OR AB "observational stud*" OR SU "observational stud*")
OR (TI "observation stud*" OR AB "observation stud*" OR SU "observation stud*") OR (TI "clinical stud*" OR AB "clinical
stud*" OR S U "clinical stud*") OR (TI surveillance OR AB surveillance OR SU surveillance) OR (TI "reporting system*" OR AB 07/31/2025 22
-
DUPLICATES
=7
UNIQUE
RECORDS
Disclaimer: The findings and conclusions herein are draft and have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or
policy . Page 23 of 24
DATABASE STRATEGY RUN DATE RECORD
COUNT
"reporting system*" OR SU "reporting system*") OR (TI VAERS OR AB VAERS OR SU VAERS) OR (TI postmarket* OR AB
postmarket* OR SU postmarket*) OR (TI post -market* OR AB post -market* OR SU post -market*))
S12 S10 OR S11
S13 S3 AND S6 AND S9 AND S12
Limiters - Exclude MEDLINE records
F. References
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Vaccines . 8 ed. Elsevier; 2023:37 -44.e7:chap 3.
2. Hosseini M -S, Jahanshahlou F, Akbarzadeh MA, Zarei M, Vaez -Gharamaleki Y. Formulating research questions for evidence -based studies. Journal of
Medicine, Surgery, and Public Health . 2024/04/01/ 2024;2:100046. doi: https://doi.org/10.1016/j.glmedi.2023.100046
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doi:10.1136/bmj -2024 -081903
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from rural Gambia. Vaccine . 29 May 2006;24(22):4701 -4708. doi:10.1016/j.vaccine.2006.03.038
5. Aamand T, Fisker AB, Correia C, Fernandes M, Clipet -Jensen C, Thysen SM. Do Pentavalent (DTwP -Hib-HBV) vaccines have sex -differential nonspecific
effects? An observational study. Observational Study
Research Support, Non -U.S. Gov't. Hum Vaccin Immunother . 12 15 2023;19(3):2288297. doi:10.1080/21645515.2023.2288297
6. Fisker AB, Biering -Sorensen S, Lund N, et al. Contrasting female -male mortality ratios after routine vaccinations with pentavalent vaccine versus measles
and yellow fever vaccine. A cohort study from urban Guinea -Bissau. Research Support, Non -U.S. Gov't. Vaccine . 08 31 2016;34(38):4551 -4557.
doi:10.1016/j.vaccine.2016.07.034
7. Fisker AB, Thysen SM. Non -live pentavalent vaccines after live measles vaccine may increase mortality. Research Support, Non -U.S. Gov't. Vaccine . 10 01
2018;36(41):6039 -6042. doi:10.1016/j.vaccine.2018.08.083
8. Garly ML, Jensen H, Martins CL, et al. Hepatitis B vaccination associated with higher female than male mortality in Guinea -Bissau: An observational
study. Pediatr Infect Dis J . December 2004;23(12):1086 -1092. doi:10.1097/01.inf.0000145700.77286.94
9. Hanifi SMA, Biering -Sorensen S, Jensen AKG, Aaby P, Bhuiya A. Penta is associated with an increased female -male mortality ratio: cohort study from
Bangladesh. Research Support, Non -U.S. Gov't. Hum Vaccin Immunother . 01 02 2021;17(1):197 -204. doi:10.1080/21645515.2020.1763084
Disclaimer: The findings and conclusions herein are draft and have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or
policy . Page 24 of 24
10. He WQ, Guo GN, Li C. The impact of hepatitis B vaccination in the United States, 1999 -2018. Hepatology . 06 2022;75(6):1566 -1578.
doi:10.1002/hep.32265
11. Morgan HJ, Nold MF, Kattan GS, et al. Hepatitis B vaccination of preterm infants and risk of bronchopulmonary dysplasia: a co hort study, Australia.
Vaccination contre l'hepatite B de prematures et risque de dysplasie bronchopulmonaire: etude de cohorte en Australie, Vacunacion contra la hepatitis B en
neonatos prematuros y riesgo de displasia broncopulmonar: estudio de cohortes en Australia. Bull World Health Organ . 2025;103(3):187 -193.
doi:10.2471/BLT.24.291683