Recommended Childhood Immunization Schedule

June 16, 1995 / Vol. 44 / No. RR-5

Recommendations

and

Reports

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES

Public Health Service

Centers for Disease Control

and Prevention (CDC)

Atlanta, Georgia 30333

Recommended Childhood Immunization

Schedule — United States, 1995

The

MMWR

series of publications is published by the Epidemiology Program Office,

Centers for Disease Control and Prevention (CDC), Public Health Service, U.S. Depart-

ment of Health and Human Services, Atlanta, GA 30333.

Centers for Disease Control and Prevention.......................... David Satcher, M.D., Ph.D.

Director

The material in this report was prepared for publication by:

National Immunization Program ...........................................Walter A. Orenstein, M.D.

Director

Epidemiology and Surveillance Division ............................ Stephen C. Hadler, M.D.

Director

The production of this report as an

MMWR

serial publication was coordinated in:

Epidemiology Program Office.................................... Stephen B. Thacker, M.D., M.Sc.

Director

Richard A. Goodman, M.D., M.P.H.

Editor,

MMWR

Series

Scientific Information and Communications Program

Recommendations and Reports

................................... Suzanne M. Hewitt, M.P.A.

Managing Editor

Rachel J. Wilson

Project Editor

Peter M. Jenkins

Visual Information Specialist

SUGGESTED CITATION

Centers for Disease Control and Prevention. Recommended childhood immuniza-

tion schedule—United States, 1995. MMWR 1995;44(No. RR-5): [inclusive page

numbers].

Copies can be purchased from Superintendent of Documents, U.S. Government

Printing Office, Washington, DC 20402-9325. Telephone: (202) 783-3238.

Use of trade names and commercial sources is for identification only and does not

imply endorsement by the Public Health Service or the U.S. Department of Health

and Human Services.

Contents

Introduction...........................................................................................................1

Rationale for Change and Current Recommendations......................................3

Simultaneous Administration of Multiple Vaccines ..........................................7

Conclusion.............................................................................................................7

References.............................................................................................................8

Vol. 44 / No. RR-5 MMWR i

Working Group

Thomas L. Copmann, Ph.D.

Pharmaceutical Research and

Manufacturers of America

Jeffrey P. Davis, M.D.

Advisory Committee on Immunization

Practices

Kathryn M. Edwards, M.D.

Advisory Committee on Immunization

Practices

Caroline B. Hall, M.D.

American Academy of Pediatrics

Neal A. Halsey, M.D.

Advisory Committee on Immunization

Practices

American Academy of Pediatrics

Carolyn Hardegree, M.D.

Food and Drug Administration

Michele Kiely, M.D.

Maternal and Child Health Bureau

Health Resources Management

Administration

Georges Peter, M.D.

American Academy of Pediatrics

Fred E. Thompson, M.D.

Advisory Committee on Immunization

Practices

Gina Rabinovitch, M.D.

National Institutes of Health

David R. Smith, M.D.

Immunization Grantee Working Group

Richard K. Zimmerman, M.D.

American Academy of Family

Physicians

ii MMWR June 16, 1995

The following CDC staff members prepared this report:

Jacqueline S. Gindler, M.D.

Stephen C. Hadler, M.D.

Peter M. Strebel, M.B.Ch.B., M.P.H.

John C. Watson, M.D., M.P.H.

Epidemiology and Surveillance Division

National Immunization Program

Vol. 44 / No. RR-5 MMWR iii

Recommended Childhood Immunization Schedule —

United States, 1995

Summary

The need for a single childhood immunization schedule prompted the unifica-

tion of previous vaccine recommendations made by the American Academy of

Pediatrics (AAP) and the Advisory Committee on Immunization Practices (ACIP).

In addition to presenting the newly recommended schedule for the administra-

tion of vaccines during childhood, this report addresses the previous differences

between the AAP and ACIP childhood vaccination schedules and the rationale

for changing previous recommendations.

INTRODUCTION

Since 1988, the U.S. childhood immunization schedule has rapidly expanded to ac-

commodate the introduction of new, universally recommended vaccines (i.e.,

Haemophilus influenzae

type b [Hib] conjugate [

1,2

] and hepatitis B [

2,3

] vaccines)

and recommendations for a second dose of measles-mumps-rubella vaccine (MMR)

(

4,5

) and the use of acellular pertussis vaccines (

2,6

). For approximately 30 years, the

Advisory Committee on Immunization Practices (ACIP) and the Committee on Infec-

tious Diseases (COID) of the American Academy of Pediatrics (AAP)—the two groups

responsible for developing vaccine recommendations for the public and private sec-

tors—worked to develop similar schedules for routine childhood vaccination.

However, some differences in the two schedules persisted. The unification of these

childhood immunization schedules is essential to issuing consistent recommenda-

tions for both private and public health practitioners and for parents.

In February 1994, a working group was convened comprising members of AAP,

ACIP, the American Academy of Family Physicians (AAFP), the Food and Drug Admini-

stration (FDA), the National Institutes of Health, and CDC. Representatives from state

immunization programs, the Maternal and Child Health Bureau of the Health Re-

sources and Services Administration, and vaccine manufacturers also participated.

The objective of this working group was to develop a single, scientifically valid child-

hood immunization schedule—presented in an easily comprehensible format—that

would accommodate the current recommendations of both ACIP and AAP and ensure

the timely vaccination of preschool-age children. The schedule would identify a speci-

fied age for administering each vaccine dose and provide an acceptable range of ages

to ensure flexibility for health-care providers. The working group also addressed the

number of antigens and injections that should be administered at each visit, the num-

ber of visits required for children by 2 years of age, the availability of combined

diphtheria and tetanus toxoids and pertussis (DTP)-Hib vaccines, and the capacity of

the schedule to accommodate newly licensed vaccines (e.g., varicella vaccine). This

report presents the recommended childhood immunization schedule (approved by

ACIP, AAP, and AAFP) (Table 1) and the rationale for changing the previous recommen-

dations. Practitioners should consult the Report of the Committee on Infectious

Diseases (Red Book) (

), the vaccine-specific recommendations of ACIP, and the

Vol. 44 / No. RR-5 MMWR 1

*Recommended vaccines are listed under the routinely recommended ages. Shaded bars

indicate range of acceptable ages for vaccination.

†

Although no changes have been made to this schedule since publication in

MMWR

(weekly)

in January 1995, this table has been revised to more accurately reflect the recommendations.

Vaccines recommended for administration at 12–15 months of age may be administered at

either one or two visits.

Infants born to hepatitis B surface antigen (HBsAg)-negative mothers should receive the

second dose of hepatitis B vaccine between 1 and 4 months of age, provided at least

1 month has elapsed since receipt of the first dose. The third dose is recommended between

6 and 18 months of age. Infants born to HBsAg-positive mothers should receive

immunoprophylaxis for hepatitis B with 0.5 mL Hepatitis B Immune Globulin (HBIG) within

12 hours of birth, and 5 µg of either Merck, Sharpe, & Dohme (West Point, Pennsylvania)

vaccine (Recombivax HB

) or 10 µg of SmithKline Beecham (Philadelphia) vaccine

(Engerix-B

) at a separate site. For these infants, the second dose of vaccine is

recommended at 1 month of age and the third dose at 6 months of age. All pregnant women

should be screened for HBsAg during an early prenatal visit.

**The fourth dose of DTP may be administered as early as 12 months of age, provided at

least 6 months have elapsed since the third dose of DTP. Combined DTP-Hib products may

be used when these two vaccines are administered simultaneously. Diphtheria and tetanus

toxoids and acellular pertussis vaccine (DTaP) is licensed for use for the fourth and/or fifth

dose of DTP in children ≥15 months of age and may be preferred for these doses in children

in this age group.

††

Three

H. influenzae

type b conjugate vaccines are available for use in infants:

a) oligosaccharide conjugate Hib vaccine (HbOC) (HibTITER

, manufactured by Praxis

Biologics, Inc. [West Henrietta, New York] and distributed by Lederle-Praxis Biologicals

[Wayne, New Jersey]); b) polyribosylribitol phosphate-tetanus toxoid conjugate (PRP-T)

(ActHIB

, manufactured by Pasteur Mérieux Sérums & Vaccins, S.A. [Lyon, France] and

distributed by Connaught Laboratories, Inc. [Swiftwater, Pennsylvania], and OmniHIB

manufactured by Pasteur Mérieux Sérums & Vaccins, S.A. and distributed by SmithKline

Beecham); and c)

Haemophilus

b conjugate vaccine (Meningococcal Protein Conjugate)

(PRP-OMP) (PedvaxHIB

, manufactured by Merck, Sharp, & Dohme). Children who have

received PRP-OMP at 2 and 4 months of age do not require a dose at 6 months of age.

After the primary infant Hib conjugate vaccine series is completed, any licensed Hib

conjugate vaccine may be administered as a booster dose at age 12–15 months.

§§

The second dose of MMR vaccine should be administered EITHER at 4–6 years of age OR

at 11–12 years of age.

Source: Advisory Committee on Immunization Practices, American Academy of Pediatrics, and

American Academy of Family Physicians.

Birth

HB-2

HB-1

HB-3

HB-2

HB-1

HB-3

DTP

or DTaP > at 15 months

OPV

Hib

MMR

DTP

or DTaP > at 15 months

Hib Hib Hib

MMR

OPV OPV

OPV

Hib

MMR MMR

DTP DTP

OPV

Poliovirus

Vaccine

Months

4 - 6

Years

11-12

Years

14-16

Years

Months

DTaP

DTP or

Hepatitis B

Haemophilus

Months

Measles-Mumps-

Rubella

Diphtheria-Tetanus-

Pertussis (DTP)**

Months

††

type b

influenzae

§§

TABLE 1. Recommended childhood immunization schedule*

†

— United States,

January 1995

2 MMWR June 16, 1995

official manufacturers’ package inserts or the Physician’s Desk Reference (PDR) (

) for

detailed information and specific recommendations for administration of vaccines.

RATIONALE FOR CHANGE AND CURRENT

RECOMMENDATIONS

In 1994, the substantial differences between the recommended AAP and ACIP

schedules included the schedule for infant hepatitis B vaccination and the timing of

the third dose of oral poliovirus vaccine (OPV) and the second dose of MMR (Table 2).

Resolution of the differences between the schedules is described in the following

sections.

OPV

Since 1963, OPV has been the recommended vaccine for inducing long-lasting im-

munity to poliomyelitis. The primary series has consisted of two doses administered

during infancy at approximately 2-month intervals beginning at 6–8 weeks of age, a

third dose recommended at 6 weeks to 14 months after the second dose (generally

administered at 15–18 months of age), and a fourth dose administered at 4–6 years of

age. In late 1993, ACIP recommended that the third dose of OPV be administered at 6

months of age (

), whereas AAP recommended that this dose be administered at 6–18

months of age (

A study comparing two infant immunization schedules (one recommending vacci-

nation at approximately 2, 4, 6, and 12 months of age and one at 2, 4, and 12 months

of age) indicated high seroconversion rates (i.e., 96%–100%) and similar geometric

mean antibody titers (measured after three doses) when following either schedule (

Several other studies have evaluated the seroresponse to OPV administered at 2, 4,

and 6 months; 2, 4, and 12 months; and 2, 4, and 18 months of age (

10–13

). These data

indicated excellent response to all serotypes of OPV when the third dose was admin-

istered at 6, 12, or 18 months of age (Table 3).

Recommendation: Because immune response is not affected by adminis-

tering the third dose of OPV at as early as 6 months of age, and because

earlier scheduling can ensure a higher rate of completion of the OPV pri-

mary series at a younger age, the third dose of OPV should be

administered routinely at 6 months of age. Vaccination at as late as 18

months of age remains an acceptable alternative.

TABLE 2. Differences between the American Academy of Pediatrics’ (AAP) and the

Advisory Committee on Immunization Practices’ (ACIP) childhood immunization

schedules, by selected vaccine — United States, 1994

Vaccine or vaccine dose AAP recommendation ACIP recommendation

OPV-3* 6–18 mos 6 mos

Hepatitis B 0–2, 1–4,

†

6–18 mos Birth, 1–2, 6–18 mos OR

2, 4, 6–18 mos

MMR-2

11–12 yrs 4–6 yrs

*The third dose of oral poliovirus vaccine.

†

Provided that at least 1 month has elapsed between the first and second doses.

The second dose of measles-mumps-rubella vaccine.

Vol. 44 / No. RR-5 MMWR 3

MMR

First Dose

During 1989 and 1990, more than 55,000 cases of measles were reported in the

United States. Nearly 25% of these cases occurred among children ≤15 months of age,

including approximately 9% among children 12–15 months of age (CDC, unpublished

data). At that time, the recommended age for routine measles vaccination was 15

months of age. Recent studies have examined the impact of vaccine-induced immu-

nity on maternally derived transplacental antibody levels; these studies have indicated

that younger women (i.e., women who were born after 1956 and who are therefore

more likely to have vaccine-induced immunity) transfer lower titers of measles anti-

bodies to their newborn infants than older women (who are more likely to have had

natural measles infection). The transplacental antibody acquired by these younger

mothers’ infants wanes earlier, causing their children to become susceptible to mea-

sles at a younger age (

14,15

). This finding suggests that children born to younger

mothers might respond well to measles vaccine administered at 12 months of age. In

one recent study in which children randomly received measles vaccine at either 12 or

15 months of age (

), the measles antibody response to MMR was 93% when the

vaccine was administered at 12 months of age; at 15 months of age, the antibody

response was 98%. Among children of mothers born after 1961, who probably had

received measles vaccine and were less likely to have had measles infection than

women born in previous years, the seroconversion rate was 96% among children vac-

cinated at 12 months of age and 98% among those vaccinated at 15 months of age.

Recommendation: The slightly lower response to the first dose of measles

vaccine when administered at 12 months of age compared with admini-

stration at 15 months of age has limited clinical importance because a

second dose of MMR is recommended routinely for all children, enhancing

the likelihood of seroconversion among children who do not respond to

the first dose. In addition, earlier scheduling of the first dose of measles

vaccine can improve vaccination coverage. In 1994, both AAP and ACIP

recommended administration of the first dose of MMR vaccine at 12–15

months of age (

2,8

); this schedule is still recommended.

TABLE 3. Percentage of children with serum-neutralizing antibody to poliovirus types

1 (p1), 2 (p2), and 3 (p3) after two and three doses of oral poliovirus vaccine, by age at

vaccination and study

Age at

vaccination

(mos) Study

After two doses (%) After three doses (%)

p1 p2 p3 p1 p2 p3

2, 4, 6 Hardy (

) 93 100 91 97 100 96

Cohen-Abbo (

) 89 100 93 99 100 99

2, 4, 12 Hardy (

) 92 99 90 96 100 96

Faden (

) 100 100 100 100 100 100

2, 4, 18 McBean (

) 92 100 96 97 100 100

Modlin (

) 95 100 90 95 100 100

4 MMWR June 16, 1995

Second Dose

In 1989, both ACIP and AAP recommended that all children receive a second dose

of measles-containing vaccine; however, ACIP recommended administering the sec-

ond dose at 4–6 years of age (

), and AAP recommended this dose at 11–12 years of

age (

). Most states have implemented school entry requirements based on one or

both of these recommendations. Currently, 12 states require administration of the sec-

ond dose of measles vaccine before children enter kindergarten (i.e., at 4–6 years of

age), 12 require this dose before entry to middle school (i.e., at 11–12 years of age),

and 13 states require that the second dose be administered before children enter

either kindergarten or middle school.

Recommendation: Because response to the second dose is high when ad-

ministered to children in either age group (CDC, unpublished data), and

because state-specific laws govern the administration of the second dose

of MMR, the second dose of MMR can be administered at either 4–6 years

of age or 11–12 years of age.

Hepatitis B

Universal hepatitis B vaccination of infants was recommended in 1991 (

3,17

). Al-

though a protective serologic response (i.e., ≥10 mIU/mL) has been demonstrated in

>95% of hepatitis B vaccine recipients who received vaccine according to several

schedules beginning at birth or 2 months of age (Table 4), higher antibody titers were

achieved when the third dose was administered at 12 or 15 months of age (

18,19

Available data indicate that higher titers of antibody ensure longer persistence of an-

tibody (

20–22

); however, the effect of high antibody levels on long-term protection

against disease is not known.

TABLE 4. Percentage of children who seroconverted and geometric mean titers (GMTs)

after vaccination with hepatitis B vaccine, by age at first dose and vaccination schedule

Age at first dose/

Vaccination schedule

(mos)

Total

no.

children

No. mos

between first

dose and

measurement

No.

doses

received*

Percentage of

children who

seroconverted

†

GMT

Birth

0, 1, 2, 12 62 9 3 95 110

46 13 4 100 647

0, 1, 6 78 9 3 96 262

0, 2, 4 49 9 3 98 99

0, 2, 6 50 9 3 98 216

2 mos

2, 4, 6 82 7 3 98 202

2, 4, 6, 15

32 14 4 100 1,793

2, 4, 12 41 11 3 100 1,633

2, 4, 12 (

) 52 11 3 98 1,358

2, 4, 15 38 14 3 97 1,527

2, 4, 15 (

) 50 14 3 100 3,424

*At the time of measurement.

†

Children who had ≥10 mIU/mL of antibody to hepatitis B surface antigen.

A subset of the infants vaccinated at 2, 4, and 6 months of age.

Source: David West, Merck Research Laboratories.

Vol. 44 / No. RR-5 MMWR 5

Recommendation: The routine hepatitis B vaccination series should begin

at birth, with the second dose administered at 2 months of age, for infants

whose mothers are hepatitis B surface antigen (HBsAg) negative. Accept-

able ranges are from birth through 2 months of age for the first dose and

from 1 through 4 months of age for the second dose, provided that at least

1 month elapses between these doses. The third dose should be adminis-

tered at 6–18 months of age. Limited available data suggest an augmented

response when the third dose is administered after 12 months of age

(Merck Research Laboratories, unpublished data, 1994). Infants of HBsAg-

positive mothers should receive the first dose of vaccine at birth (along

with immunoprophylaxis with hepatitis B immune globulin); the second

dose at 1 month of age; and the third dose at 6 months of age.

Diphtheria and Tetanus Toxoids and Pertussis Vaccine (DTP)

Since the late 1940s, the approved schedule for DTP has consisted of a primary

series of three doses administered at 4–8 week intervals and a fourth (i.e., reinforcing)

dose administered 6–12 months after the third dose. Although the fourth dose has

been administered routinely at 15–18 months of age, it may be administered as early

as 12 months of age, provided that at least 6 months elapse between the third and

fourth dose. No recent data are available comparing the immunogenicity of DTP or

diphtheria and tetanus toxoids and acellular pertussis vaccine (DTaP) when adminis-

tered at 12–14 months with immunogenicity at 15–18 months of age when vaccine is

either administered alone or simultaneously with MMR and Hib vaccines.

Recommendation: The current schedule for DTP vaccination is still recom-

mended—including the option that the fourth dose may be administered

at as early as 12 months of age if 6 months elapse after the third dose.

Thus, the fourth dose of DTP can be scheduled with other vaccines that are

administered at 12–18 months of age. DTaP currently is licensed for use

only as the fourth and/or fifth dose of the DTP series for children ≥15

months of age (

2,6

Tetanus and Diphtheria Toxoids, Adsorbed,

For Adult Use (Td)

For most persons who received a dose of DTP vaccine at 4–6 years of age, the

first dose of Td is administered at 14–16 years of age and every 10 years thereafter

to maintain adequate protection against tetanus and diphtheria (

). A recent U.S.

serologic survey of tetanus immunity (

) indicated that tetanus immunity in the ma-

jority of the population decreases with time after the administration of the recipient’s

most recent vaccination. Among persons 6–16 years of age who had received their

most recent tetanus vaccination 6–10 years previously, 28% had tetanus antibody tit-

ers lower than protective levels, which suggested that Td could be administered as

early as 11–12 years of age.

Recommendation: The booster dose of Td should be administered at 11–

12 years of age, although vaccination at 14–16 years of age is an

acceptable alternative. The earlier scheduling of this dose at 11–12 years of

6 MMWR June 16, 1995

age encourages a routine preadolescent preventive care visit. During this

visit, the practitioner should also administer a second dose of measles-

containing vaccine to those persons who have not already received this

dose and should ensure that children who previously have not received

hepatitis B vaccine begin the vaccination series. Adolescent hepatitis B

vaccination currently is recommended by AAP (

); ACIP will issue a simi-

lar recommendation. A routine visit at 11–12 years of age also will facilitate

administration of other needed vaccines to adolescents.

SIMULTANEOUS ADMINISTRATION OF MULTIPLE VACCINES

Simultaneous administration of vaccines has been recommended through the ad-

ministration of combined vaccines (e.g., DTP vaccine, trivalent OPV, and MMR

vaccine) or administration of multiple vaccines at different sites or by different routes

(e.g., simultaneous administration of DTP, OPV, and Hib). Several studies have exam-

ined the safety and immunogenicity of simultaneously administered MMR and Hib

(

24,25

); DTP, OPV, and MMR (

26,27

); DTP, OPV, and Hib (

25,28

); hepatitis B, DTP, and

OPV (

29–31

); and hepatitis B and MMR (Merck Research Laboratories, unpublished

data, 1993). Hepatitis B vaccine, the vaccine most recently licensed for use among

infants, has been shown to be safe and effective when administered from birth

through 15 months of age with other routinely recommended childhood vaccines (D.

Greenberg, personal communication, 1994) (

). The available safety and immuno-

genicity data for vaccines currently recommended by ACIP and AAP have been

reviewed recently (

). Although data are limited concerning the simultaneous ad-

ministration of the entire recommended vaccine series (i.e., DTP, OPV, MMR, and Hib

vaccines, with or without hepatitis B vaccine), data from numerous studies have indi-

cated no interference between routinely recommended childhood vaccines (either

live, atttenuated or killed) (

). These findings support the simultaneous use of all

vaccines as recommended.

CONCLUSION

The development of a unified childhood immunization schedule approved by ACIP,

AAP, and AAFP represents the beginning of a process that will ensure continued col-

laboration among the recommending groups, the pharmaceutical manufacturing

industry, and FDA to maintain and work toward further simplification of a unified

schedule. The recommended childhood immunization schedule will be updated and

published annually.

Since the development of these recommendations in January 1995, FDA has li-

censed varicella zoster virus vaccine for use among susceptible persons ≥12 months

of age. The ACIP will publish recommendations for this new vaccine, and these recom-

mendations will be incorporated into the 1996 Recommended Childhood

Immunization Schedule.

Vol. 44 / No. RR-5 MMWR 7

References

1. ACIP.

Haemophilus

b conjugate vaccines for prevention of

Haemophilus influenzae

type b

disease among infants and children two months of age and older: recommendations of the

Immunization Practices Advisory Committee. MMWR 1991;40(No. RR-1):1–7.

2. American Academy of Pediatrics. Active and passive immunization. In: Peter G, ed. 1994 Red

Book: report of the Committee on Infectious Diseases. 23rd ed. Elk Grove Village, IL: American

Academy of Pediatrics, 1994:1–67.

3. ACIP. Hepatitis B virus: a comprehensive strategy for eliminating transmission in the United

States through universal childhood vaccination: recommendations of the Immunization Prac-

tices Advisory Committee. MMWR 1991;40(No. RR-13):1–25.

4. American Academy of Pediatrics, Committee on Infectious Diseases. Measles: reassessment

of the current immunization policy. Pediatrics 1989;84:110–1.

5. ACIP. Measles prevention: recommendations of the Immunization Practices Advisory Com-

mittee (ACIP). MMWR 1989;38(No. S-9):1–18.

6. ACIP. Pertussis vaccination: acellular pertussis vaccine for reinforcing and booster use—sup-

plementary ACIP statement: recommendations of the Advisory Committee on Immunization

Practices. MMWR 1992;41(No. RR-1):1–10.

7. Medical Economics Company. Physician’s desk reference. 49th ed. Montvale, NJ: Medical Eco-

nomics Company Inc, 1995.

8. ACIP. General recommendations on immunization: recommendations of the Advisory Com-

mittee on Immunization Practices (ACIP). MMWR 1994;43(No. RR-1):1–38.

9. Hardy GE, Hopkins CC, Linnemann CC, Hatch MH, Chambers JC, Witte JJ. Trivalent oral

poliovirus vaccine: a comparison of two infant immunization schedules. Pediatrics

1970;45:444–8.

10. Cohen-Abbo A, Culley BS, Reed GW, et al. Seroresponse to trivalent oral poliovirus vaccine

as a function of dosage interval. Pediatr Infect Dis J 1995;4:100–6.

11. Faden H, Modlin JF, Thomas ML, McBean AM, Ferdon MB, Ogra PL. Comparative evaluation

of immunization with live attenuated and enhanced-potency inactivated trivalent poliovirus

vaccines in childhood: systemic and local immune responses. J Infect Dis 1990;162:1291–7.

12. McBean AM, Thoms ML, Albrecht P, Cuthie JC, Bernier R. Serologic response to oral polio

vaccine and enhanced-potency inactivated polio vaccines. Am J Epidemiol 1988;128:615–28.

13. Modlin JF, Halsey NA, Thoms ML, Meschievitz CK, Patriarca P. Serum neutralizing antibody

response to three experimental sequential IPV-OPV immunization schedules [Abstract]. In:

Programs and abstracts of the 33rd Interscience Conference on Antimicrobial Agents and Che-

motherapy. New Orleans, LA: ICAAC, 1993.

14. Lennon JL, Black FL. Maternally derived measles immunity in era of vaccine-protected moth-

ers. J Pediatr 1986;108:671–6.

15. Jenks PJ, Caul EO, Roome AP. Maternally derived measles immunity in children of naturally

infected and vaccinated mothers. Epidemiol Infect 1988;101:473–6.

16. King GE, Markowitz LE. A comparison of seroconversion rates to MMR vaccine of children

vaccinated at 9, 12, or 15 months of age [Abstract]. In: Programs and abstracts of the 34th

Interscience Conference on Antimicrobial Agents and Chemotherapy. Orlando, FL: ICAAC,

1994.

17. American Academy of Pediatrics, Committee on Infectious Diseases. Universal hepatitis B

immunization. Pediatrics 1992;89:795–800.

18. Keyserling HL, West DJ, Hesley TM, Bosley C, Wiens BL, Calandra GB. Antibody responses

of healthy infants to a recombinant hepatitis B vaccine administered at two, four, and twelve

or fifteen months of age. J Pediatr 1994;125:67–9.

19. Jilg W, Schmidt M, Deinhardt F. Vaccination against hepatitis B: comparison of three different

vaccination schedules. J Infect Dis 1989;160:766–9.

20. Stevens CE, Toy PT, Taylor PE, Lee T, Yip H. Prospects for control of hepatitis B virus infection:

implications of childhood vaccination and long-term protection. Pediatrics 1992;20(suppl):

170–3.

21. Wainwright RB, McMahon BJ, Bulkow LR, et al. Duration of immunogenicity and efficacy of

hepatitis B vaccine in a Yupik Eskimo population. JAMA 1989;261:2362–6.

22. Jilg W, Schmidt M, Deinhardt F. Persistence of specific antibodies after hepatitis B vaccination.

J Hepatol 1988;6:201–7.

8 MMWR June 16, 1995

23. Gergen PJ, McQuillan GM, Kiely M, Ezzati-Rice TM, Sutter RW, Virella G. A population-based

serological survey of tetanus immunity: implications for U.S. vaccination policy. N Engl J

Med 1995 (in press).

24. Steinhoff MC, Thomas ML, Dannelfelser S, O’Donovan C. Immunogenicity of

H. influenzae

type B-CRM

197

conjugate vaccine (HbOC) given simultaneously with routine childhood im-

munizations. Pediatr Res 1990;27:184A.

25. Dashefsky B, Wald E, Guerra N, Byers C. Safety, tolerability, and immunogenicity of concurrent

administration of

Haemophilus influenzae

type b conjugate vaccine (meningococcal protein

conjugate) with either measles-mumps-rubella vaccine or diphtheria-tetanus-pertussis and

oral poliovirus vaccines in 14- to 23-month old infants. Pediatrics 1990;85(suppl):682–9.

26. Deforest A, Long SS, Lischner HW, et al. Simultaneous administration of measles-mumps-

rubella vaccine with booster doses of diphtheria-tetanus-pertussis and poliovirus vaccines.

Pediatrics 1988;81:237–46.

27. Berger R, Just M. Lack of interference between vaccines [Letter]. Pediatr Infect Dis J 1983;2:172.

28. Booy R, Moxon ER, MacFarlane JA, Mayon-White RT, Slack MPE. Efficacy of

Haemophilus

influenzae

type B conjugate vaccine in Oxford Region [Letter]. Lancet 1992;340:847.

29. Greenberg DP, Vadheim SM, Marcy SM, Wong V, Margolis H, Ward JI. Safety and immuno-

genicity of two recombinant hepatitis B vaccines given to 5000 infants as part of routine

immunization at 2, 4, and 6 months of age. In: Program and abstracts of the 31st Interscience

Conference on Antimicrobial Agents and Chemotherapy. Chicago, IL: ICAAC, 1991.

30. Huang LM, Lee CY, Hsu CY, et al. Effect of monovalent measles and trivalent measles-mumps-

rubella vaccines at various ages and concurrent administration with hepatitis B vaccine. Pediatr

Infect Dis J 1990;9:461–5.

31. Barone P, Mauro L, Leonardi S, et al. Simultaneous administration of HB recombinant vaccine

with diphtheria and tetanus toxoid and oral polio vaccine: a pilot study. Acta Paediatr Jpn

1991;33:455–8.

32. Greenberg DP, Vadheim CM, Marcy SM, et al. Comparative safety and immunogenicity of

two recombinant Hepatitis B (HBV) vaccines given to infants at 2, 4, and 6 months of age

[Abstract]. In: Program and abstracts of the 32nd Interscience Conference on Antimicrobial

Agents and Chemotherapy. Anaheim, CA: ICAAC, 1992:264.

33. King GE, Hadler SC. Simultaneous administration of childhood vaccines: an important public

health policy that is safe and efficacious. Pediatr Infect Dis J 1994;13:394–407.

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