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February 7, 1996, Vol 275, No. 5 >
ARTICLE | February 7, 1996

Evaluating New Vaccines for Developing Countries: Title and subTitle BreakEfficacy or Effectiveness? FREE

John Clemens, MD; Ruth Brenner, MD, MPH; Malla Rao, MEngg; Nebiat Tafari, MD; Charles Lowe, MD
[+] Author Affiliations

This article is one of a series addressing emerging and reemerging global microbial threats.

Reprint requests to Epidemiology Branch, National Institutes of Health/NICHD, Bldg 6100, Room 7B03, Bethesda, MD 20892 (Dr Clemens).


JAMA. 1996;275(5):390-397. doi:10.1001/jama.1996.03530290060038
Text Size: A A A
Published online
Article
References

Despite the profusion of promising new vaccines against illnesses prevalent in developing countries, uncertainties about the balance between costs and benefits of new vaccines have retarded their use in public health practice. Conventional prelicensure trials of vaccine protection exacerbate these uncertainties by focusing on measurement of vaccine efficacy—the performance of a vaccine under idealized conditions. Vaccine effectiveness trials provide a more pragmatic perspective by addressing the performance of a vaccine under the ordinary conditions of a public health program, by capturing direct as well as indirect effects of vaccination, and by comprehensively addressing outcomes of public health concern. The use of effectiveness trials should enable more rational triaging of new vaccines for developing countries and may accelerate the introduction of new vaccines into public health practice by resolving speculative debates about practical costs and benefits.

(JAMA. 1996;275:390-397)

REFERENCES

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2 +
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3 +
The World Bank. World Development Report: Investing in Health . Oxford, England: Oxford University Press; 1993;.
4 +
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5 +
Clemens J, Stanton B.  Longer term evaluations of vaccine efficacy.  In: Woodrow GC, Levine MM, eds. New Generation Vaccines . New York, NY: Marcel Dekker Inc; 1990;:51-68.
6 +
Begg N, Miller, E.  Role of epidemiology in vaccine policy. Vaccine . 1990;;8:180-189.
7 +
Basch PF. Vaccines and World Health: Science, Policy, and Practice . New York, NY: Oxford University Press; 1994;:95-122.
8 +
Clemens J, Sack D, Harris J, et al.  Field trial of oral cholera vaccines in Bangladesh: results from long-term follow-up. Lancet . 1990;;335:270-273.
9 +
Pierce N, Robinson D, Rigal J, Dualeh M.  Cholera treatment. Lancet . 1994;;344:1022.
10 +
Glass R, Claeson M, Blake P, et al.  Cholera in Africa: lessons on transmission and control for Latin America. Lancet . 1991;;338:791-795.
11 +
Sack D.  Cholera control. Lancet . 1994;;344:616-617.
12 +
Swerdlow D, Levine O.  Cholera control among Rwandan refugees in Zaire. Lancet . 1994;;344:1302-1303.
13 +
Blok L, Sondorp E.  Cholera treatment. Lancet . 1994;;344:1022-1023.
14 +
Simanjuntak CH, Paleologo FP, Punjabi NH, et al.  Oral immunization against typhoid fever in Indonesia with Ty21a vaccine. Lancet . 1991;;338: 1055-1059.
15 +
Levine M, Ferreccio C, Black R, et al.  Large-scale field trial of Ty21a live oral typhoid vaccine in enteric-coated capsule formulation. Lancet . 1987;; 1:1049-1052.
16 +
Ferreccio C, Levine M, Rodriguez H, et al.  Comparative efficacy of two, three, or four doses of Ty21a live oral typhoid vaccine in enteric-coated capsules: a field trial in an endemic area. J Infect Dis . 1989;;159:766-769.
17 +
Levine M, Ferreccio C, Cryz S, Ortiz E.  Comparison of enteric-coated capsules and liquid formulation of Ty21a typhoid vaccine in a randomised controlled field trial. Lancet . 1990;;336:891-894.
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19 +
Klugman K, Gilbertson I, Korrnhof H, et al.  Protective activity of Vi polysaccharide vaccine against typhoid fever. Lancet . 1987;;2:1165-1169.
20 +
Ivanoff B, Levine M, Lambert P.  Vaccination against typhoid fever: present status. Bull World Health Organ . 1994;;72:957-971.
21 +
Santosham M, Wolff M, Reid R, et al.  The efficacy in Navajo infants of a conjugate vaccine consisting of Haemophilus influenzae type b polysaccharide and Neisseria meningitidis outer membrane protein complex. N Engl J Med . 1991;;324:1767-1772.
22 +
Black S, Shinefield H, Fireman B, et al.  Efficacy in infancy of oligosaccharide conjugate Haemophilus influenzae type b (HbOC) vaccine in a United States population of 61,080 children. Pediatr Infect Dis . 1991;;10:97-104.
23 +
Booy R, Hodgson S, Carpenter L, et al.  Efficacy of Haemophilus influenzae type b conjugate vaccine PRP-T. Lancet . 1994;;344:362-366.
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Clemens J.  Assessing the value of enteric vaccines: efficacy, effectiveness, and efficiency.  In: Sack D, Freij L, Holmgren J, eds. Prospects for Public Health Benefits in Developing Countries From New Vaccines Against Enteric Infections . Göteborg, Sweden: SAREC Documentation; 1990;:131-140. Conference report 2.
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Donner A.  Approaches to sample size estimation in the design of clinical trials—a review. Stat Med . 1984;;3:199-212.
30 +
Fine P.  Herd immunity: history, theory, practice. Epidemiol Rev . 1993;;15:265-302.
31 +
Halloran M, Haber M, Longini I, et al.  Direct and indirect effects in vaccine efficacy and effectiveness. Am J Epidemiol . 1991;;133:323-331.
32 +
Halloran M, Struchiner C.  Study designs for dependent happenings. Epidemiology . 1991;;2:331-338.
33 +
Vesikari T, Isolauri E, D'Hondt, E, et al.  Protection of infants against rotavirus diarrhoea by RIT 4237 attenuated bovine rotavirus strain vaccine. Lancet . 1984;;2:977-981.
34 +
Hanlon P, Hanlon L, Marsh V, et al.  Trial of an attenuated bovine rotavirus vaccine (RIT 4237) in Gambian infants. Lancet . 1987;;1:1342-1345.
35 +
Lanata C, Black RE, del Aguila R, et al.  Protection of Peruvian children against rotavirus diarrhea of specific serotypes by one, two, or three doses of the RIT 4237 attenuated bovine rotavirus vaccine. J Infect Dis . 1989;;159:452-459.
36 +
De Mol P, Zissis G, Butzler J, et al.  Failure of live, attenuated oral rotavirus vaccine. Lancet . 1986;; 2:108.
37 +
Wahdan M, Serie C, Derisier Y, et al.  A controlled field trial of live Salmonella typhi strain Ty21a oral vaccine against typhoid. J Infect Dis . 1982;;145:292-295.
38 +
Eskola J, Kayhty H, Takala A, et al.  A randomized, prospective field trial of a conjugate vaccine in the protection of infants and young children against invasive Haemophilus influenzae type b disease. N Engl J Med . 1990;;323:1381-1387.
39 +
Ward J, Brenneman G, Letson G, et al.  Limited efficacy of a Haemophilus influenzae type b conjugate vaccine in Alaska native infants. N Engl J Med . 1990;;323:1393-1401.
40 +
Hosmer D, Lemshaw S. Applied Logistic Regression . New York, NY: John Wiley & Sons; 1989;: 38-133.
41 +
Orenstein W, Bernier R, Hinman A.  Assessing vaccine efficacy in the field: further observations. Epidemiol Rev . 1988;;10:212-241.
42 +
Orenstein W, Bernier R, Dondero T, et al.  Field evaluation of vaccine efficacy. Bull World Health Organ . 1985;;63:1055-1068.
43 +
Clemens J, Shapiro E.  Resolving the pneumococcal vaccine controversy: are there alternatives to randomized clinical trials? Rev Infect Dis . 1984;; 6:589-600.
44 +
Markowitz L, Katz S.  Measles vaccine.  In: Plotkin S, Mortimer E, eds. Vaccines . 2nd ed. Philadelphia, Pa: WB Saunders; 1994;:229-276.
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Melnick J.  Live attenuated poliovirus vaccines.  In: Plotkin S, Mortimer E, eds. Vaccines . 2nd ed. Philadelphia, Pa: WB Saunders; 1994;:155-204.
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Pichichero ME.  Effect of breast-feeding on oral rhesus rotavirus vaccine seroconversion: a meta-analysis. J Infect Dis . 1990;;162:753-755.
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Vadheim C, Greenberg D, Eriksen E, et al.  Eradication of Haemophilus influenzae type b disease in Southern California. Arch Pediatr Adolesc Med . 1994;;48:51-56.
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51 +
Aaby P, Jensen TG, Hansen H, et al.  Trial of high-dose Edmonston-Zagreb measles vaccine in Guinea-Bissau: protective efficacy. Lancet . 1988;;2: 809-811.
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Expanded Programme on Immunization.  Safety and efficacy of high titre measles vaccine at 6 months of age. Wkly Epidemiol Rec . 1991;;66:259-261.
54 +
Garenne M, Leroy O, Beau F, Sene I.  Child mortality after high-titre measles vaccines: prospective study in Senegal. Lancet . 1991;;338:903-920.
55 +
Aaby P, Samb B, Simondon F, et al.  Divergent mortality for male and female recipients of low-titre and high-titre measles vaccines in rural Senegal. Am J Epidemiol . 1993;;138:746-755.
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Expanded Programme on Immunization.  Safety of high titre measles vaccine. Wkly Epidemiol Rec . 1992;;67:357-361.
57 +
Expanded Programme on Immunization.  Measles immunization before 9 months of age. Wkly Epidemiol Rec . 1990;;65:2-8.
58 +
Clemens J, Spriggs D, Sack D.  Public health considerations for the use of cholera vaccines in cholera control programs.  In: Wachsmuth IK, Blake P, Olsvik O, eds. Vibrio cholerae and Cholera . Washington, DC: ASM Press; 1994;:425-442.
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Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

1 +
Robbins A, Freeman P, Powell KR.  International childhood vaccine initiative. Pediatr Infect Dis . 1993;;12:523-527.
2 +
Lee JW.  Children's vaccine initiative. Science . 1994;;266:527-528.
3 +
The World Bank. World Development Report: Investing in Health . Oxford, England: Oxford University Press; 1993;.
4 +
Harrington D.  Initial clinical evaluation of new vaccine candidates: phase I and phase II trials of safety, immunogenicity, and preliminary efficacy.  In: Woodrow GC, Levine MM, eds. New Generation Vaccines . New York, NY: Marcel Dekker Inc; 1990;: 43-50.
5 +
Clemens J, Stanton B.  Longer term evaluations of vaccine efficacy.  In: Woodrow GC, Levine MM, eds. New Generation Vaccines . New York, NY: Marcel Dekker Inc; 1990;:51-68.
6 +
Begg N, Miller, E.  Role of epidemiology in vaccine policy. Vaccine . 1990;;8:180-189.
7 +
Basch PF. Vaccines and World Health: Science, Policy, and Practice . New York, NY: Oxford University Press; 1994;:95-122.
8 +
Clemens J, Sack D, Harris J, et al.  Field trial of oral cholera vaccines in Bangladesh: results from long-term follow-up. Lancet . 1990;;335:270-273.
9 +
Pierce N, Robinson D, Rigal J, Dualeh M.  Cholera treatment. Lancet . 1994;;344:1022.
10 +
Glass R, Claeson M, Blake P, et al.  Cholera in Africa: lessons on transmission and control for Latin America. Lancet . 1991;;338:791-795.
11 +
Sack D.  Cholera control. Lancet . 1994;;344:616-617.
12 +
Swerdlow D, Levine O.  Cholera control among Rwandan refugees in Zaire. Lancet . 1994;;344:1302-1303.
13 +
Blok L, Sondorp E.  Cholera treatment. Lancet . 1994;;344:1022-1023.
14 +
Simanjuntak CH, Paleologo FP, Punjabi NH, et al.  Oral immunization against typhoid fever in Indonesia with Ty21a vaccine. Lancet . 1991;;338: 1055-1059.
15 +
Levine M, Ferreccio C, Black R, et al.  Large-scale field trial of Ty21a live oral typhoid vaccine in enteric-coated capsule formulation. Lancet . 1987;; 1:1049-1052.
16 +
Ferreccio C, Levine M, Rodriguez H, et al.  Comparative efficacy of two, three, or four doses of Ty21a live oral typhoid vaccine in enteric-coated capsules: a field trial in an endemic area. J Infect Dis . 1989;;159:766-769.
17 +
Levine M, Ferreccio C, Cryz S, Ortiz E.  Comparison of enteric-coated capsules and liquid formulation of Ty21a typhoid vaccine in a randomised controlled field trial. Lancet . 1990;;336:891-894.
18 +
Acharya V, Shrestha M, Cadoz M, et al.  Prevention of typhoid fever in Nepal with the Vi polysaccharide of Salmonella typhi: a preliminary report. N Engl J Med . 1987;;317:1101-1104.
19 +
Klugman K, Gilbertson I, Korrnhof H, et al.  Protective activity of Vi polysaccharide vaccine against typhoid fever. Lancet . 1987;;2:1165-1169.
20 +
Ivanoff B, Levine M, Lambert P.  Vaccination against typhoid fever: present status. Bull World Health Organ . 1994;;72:957-971.
21 +
Santosham M, Wolff M, Reid R, et al.  The efficacy in Navajo infants of a conjugate vaccine consisting of Haemophilus influenzae type b polysaccharide and Neisseria meningitidis outer membrane protein complex. N Engl J Med . 1991;;324:1767-1772.
22 +
Black S, Shinefield H, Fireman B, et al.  Efficacy in infancy of oligosaccharide conjugate Haemophilus influenzae type b (HbOC) vaccine in a United States population of 61,080 children. Pediatr Infect Dis . 1991;;10:97-104.
23 +
Booy R, Hodgson S, Carpenter L, et al.  Efficacy of Haemophilus influenzae type b conjugate vaccine PRP-T. Lancet . 1994;;344:362-366.
24 +
Egan W, Frasch C, Anthony B.  Lot-release criteria, postlicensure quality control, and the Haemophilus influenzae type b conjugate vaccines. JAMA . 1995;;273:888-889.
25 +
Sackett DL.  On some prerequisites for a successful clinical trial.  In: Shapiro S, Louis T, eds. Clinical Trials: Issues and Approaches . New York, NY: Marcel Dekker Inc; 1983;:65-80.
26 +
Schwartz D, Flamant R, Lellouch J. Clinical Trials . London, England: Academic Press; 1980;.
27 +
Greenwood M, Yule U.  The statistics of anti-typhoid and anti-cholera inoculations, and the interpretation of such statistics in general. Proc R Soc Med . 1915;;8(pt 2):113-194.
28 +
Clemens J.  Assessing the value of enteric vaccines: efficacy, effectiveness, and efficiency.  In: Sack D, Freij L, Holmgren J, eds. Prospects for Public Health Benefits in Developing Countries From New Vaccines Against Enteric Infections . Göteborg, Sweden: SAREC Documentation; 1990;:131-140. Conference report 2.
29 +
Donner A.  Approaches to sample size estimation in the design of clinical trials—a review. Stat Med . 1984;;3:199-212.
30 +
Fine P.  Herd immunity: history, theory, practice. Epidemiol Rev . 1993;;15:265-302.
31 +
Halloran M, Haber M, Longini I, et al.  Direct and indirect effects in vaccine efficacy and effectiveness. Am J Epidemiol . 1991;;133:323-331.
32 +
Halloran M, Struchiner C.  Study designs for dependent happenings. Epidemiology . 1991;;2:331-338.
33 +
Vesikari T, Isolauri E, D'Hondt, E, et al.  Protection of infants against rotavirus diarrhoea by RIT 4237 attenuated bovine rotavirus strain vaccine. Lancet . 1984;;2:977-981.
34 +
Hanlon P, Hanlon L, Marsh V, et al.  Trial of an attenuated bovine rotavirus vaccine (RIT 4237) in Gambian infants. Lancet . 1987;;1:1342-1345.
35 +
Lanata C, Black RE, del Aguila R, et al.  Protection of Peruvian children against rotavirus diarrhea of specific serotypes by one, two, or three doses of the RIT 4237 attenuated bovine rotavirus vaccine. J Infect Dis . 1989;;159:452-459.
36 +
De Mol P, Zissis G, Butzler J, et al.  Failure of live, attenuated oral rotavirus vaccine. Lancet . 1986;; 2:108.
37 +
Wahdan M, Serie C, Derisier Y, et al.  A controlled field trial of live Salmonella typhi strain Ty21a oral vaccine against typhoid. J Infect Dis . 1982;;145:292-295.
38 +
Eskola J, Kayhty H, Takala A, et al.  A randomized, prospective field trial of a conjugate vaccine in the protection of infants and young children against invasive Haemophilus influenzae type b disease. N Engl J Med . 1990;;323:1381-1387.
39 +
Ward J, Brenneman G, Letson G, et al.  Limited efficacy of a Haemophilus influenzae type b conjugate vaccine in Alaska native infants. N Engl J Med . 1990;;323:1393-1401.
40 +
Hosmer D, Lemshaw S. Applied Logistic Regression . New York, NY: John Wiley & Sons; 1989;: 38-133.
41 +
Orenstein W, Bernier R, Hinman A.  Assessing vaccine efficacy in the field: further observations. Epidemiol Rev . 1988;;10:212-241.
42 +
Orenstein W, Bernier R, Dondero T, et al.  Field evaluation of vaccine efficacy. Bull World Health Organ . 1985;;63:1055-1068.
43 +
Clemens J, Shapiro E.  Resolving the pneumococcal vaccine controversy: are there alternatives to randomized clinical trials? Rev Infect Dis . 1984;; 6:589-600.
44 +
Markowitz L, Katz S.  Measles vaccine.  In: Plotkin S, Mortimer E, eds. Vaccines . 2nd ed. Philadelphia, Pa: WB Saunders; 1994;:229-276.
45 +
Melnick J.  Live attenuated poliovirus vaccines.  In: Plotkin S, Mortimer E, eds. Vaccines . 2nd ed. Philadelphia, Pa: WB Saunders; 1994;:155-204.
46 +
Pappaioanou M, Fishbein D, Dreesen D, et al.  Antibody response to preexposure human diploidcell rabies vaccine given concurrently with chloroquine. N Engl J Med . 1986;;314:280-284.
47 +
Pichichero ME.  Effect of breast-feeding on oral rhesus rotavirus vaccine seroconversion: a meta-analysis. J Infect Dis . 1990;;162:753-755.
48 +
Vadheim C, Greenberg D, Eriksen E, et al.  Eradication of Haemophilus influenzae type b disease in Southern California. Arch Pediatr Adolesc Med . 1994;;48:51-56.
49 +
Centers for Disease Control and Prevention.  Progress toward elimination of Haemophilus influenzae type b disease among infants and children— United States, 1987-93. MMWR Morb Mortal Wkly Rep . 1994;;43:144-146.
50 +
Hall A, Aaby P.  Tropical trials and tribulations. Int J Epidemiol . 1990;;19:777-781.
51 +
Aaby P, Jensen TG, Hansen H, et al.  Trial of high-dose Edmonston-Zagreb measles vaccine in Guinea-Bissau: protective efficacy. Lancet . 1988;;2: 809-811.
52 +
Whittle H, Hanlon P, O'Neill K, et al.  Trial of high-dose Edmonston-Zagreb measles vaccine in The Gambia: antibody response and side-effects. Lancet . 1988;;2:811-814.
53 +
Expanded Programme on Immunization.  Safety and efficacy of high titre measles vaccine at 6 months of age. Wkly Epidemiol Rec . 1991;;66:259-261.
54 +
Garenne M, Leroy O, Beau F, Sene I.  Child mortality after high-titre measles vaccines: prospective study in Senegal. Lancet . 1991;;338:903-920.
55 +
Aaby P, Samb B, Simondon F, et al.  Divergent mortality for male and female recipients of low-titre and high-titre measles vaccines in rural Senegal. Am J Epidemiol . 1993;;138:746-755.
56 +
Expanded Programme on Immunization.  Safety of high titre measles vaccine. Wkly Epidemiol Rec . 1992;;67:357-361.
57 +
Expanded Programme on Immunization.  Measles immunization before 9 months of age. Wkly Epidemiol Rec . 1990;;65:2-8.
58 +
Clemens J, Spriggs D, Sack D.  Public health considerations for the use of cholera vaccines in cholera control programs.  In: Wachsmuth IK, Blake P, Olsvik O, eds. Vibrio cholerae and Cholera . Washington, DC: ASM Press; 1994;:425-442.
59 +
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To understand the clinical management of acute heart failure syndromes.
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Compression-Only CPR: Pushing the Science Forward
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