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Zhang Y, Zhang H, Wang B, Song G, Hayden JC, Amirthalingam P, Rahmani J, Bhagavathula AS, Li Z. Pregnancy outcomes after a mass vaccination campaign with an oral cholera vaccine: a systematic review and meta-analysis. BJOG 2020; 127:1066-1073. [PMID: 32289871 DOI: 10.1111/1471-0528.16260] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/20/2020] [Indexed: 02/03/2023]
Abstract
BACKGROUND Cholera has harmful effects on the fetus but safety data on the oral cholera vaccine in pregnant women are controversial. OBJECTIVES We conducted the first meta-analysis of studies in pregnant women comparing the effect of oral cholera vaccination on pregnancy outcomes with unvaccinated women. Outcomes of interest were adverse pregnancy outcome, miscarriage, stillbirth, preterm delivery, low birthweight, abortion and malformation. SEARCH STRATEGY The search was run in MEDLINE/PubMed, SCOPUS and Embase databases from inception up to December 2019. SELECTION CRITERIA Inclusion criteria were: (1) studies that investigated the association between oral cholera vaccines and adverse pregnancy outcomes; (2) studies that reported outcomes with appropriate estimates; and (3) studies that contained an unvaccinated control group. DATA COLLECTION AND ANALYSIS A random-effects model (DerSimonian and Laird) was run to evaluate the overall treatment effect (relative risk, RR). The PRISMA statement was followed in reporting this meta-analysis. MAIN RESULTS Five studies included in meta-analysis with 5584 women (2920 exposed and 2664 not exposed). No significant increase in adverse pregnancy outcome (RR 1.03, 95% CI 0.79-1.34), miscarriage (RR 1.15, 95% CI 0.84-1.57) or stillbirth (RR 1.11, 95% CI 0.69-1.80) following cholera vaccine administration was found compared with control group. There was also no association with an increased risk of preterm delivery (RR 0.61, 95% CI 0.35-1.06) low birthweight (RR 0.84, 95% CI 0.56- 1.26), accidental abortion (RR 1.02, 95% CI 0.77-1.35) or malformation (RR 0.70, 95% CI 0.22-2.25). CONCLUSIONS This study shows no evidence of an association between oral cholera vaccination and adverse pregnancy outcomes. The findings do not rigorously exclude the possibility that the vaccine protocol may result in some degree of harm. TWEETABLE ABSTRACT There is no evidence of an association between oral cholera vaccination and adverse pregnancy outcomes. The findings do not rigorously exclude the possibility that the vaccine protocol may result in some degree of harm.
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Affiliation(s)
- Y Zhang
- Department of Obstetrics, The Fourth People's Hospital of Jinan City, Jinan, Shandong Province, China
| | - H Zhang
- Department of Integrated Treatment Area 1, Affiliated Jinan Third Hospital of Jining Medical University, Jining Medical University, Jinan, Shandong Province, China
| | - B Wang
- Department of Paediatrics, Jinan Maternity and Child Hospital, Jinan, Shandong Province, China
| | - G Song
- Department of Obstetrics, Jinan Maternity and Child Hospital, Jinan, Shandong Province, China
| | - J C Hayden
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - P Amirthalingam
- Department of Pharmacy Practice, Faculty of Pharmacy, University of Tabuk, Tabuk, Kingdom of Saudi Arabia
| | - J Rahmani
- Department of Community Nutrition, Student Research Committee, Faculty of Nutrition and Food Technology, National Nutrition and Food Technology Research Institute, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - A S Bhagavathula
- Department of Internal Medicine, College of Medicine and Health Sciences, UAE University, Al Ain, UAE
| | - Z Li
- Department of Endocrinology, The Fourth People's Hospital of Jinan City, Jinan, Shandong Province, China
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Clemens JD, Nair GB, Ahmed T, Qadri F, Holmgren J. Cholera. Lancet 2017; 390:1539-1549. [PMID: 28302312 DOI: 10.1016/s0140-6736(17)30559-7] [Citation(s) in RCA: 240] [Impact Index Per Article: 34.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 11/01/2016] [Accepted: 12/15/2016] [Indexed: 12/30/2022]
Abstract
Cholera is an acute, watery diarrhoeal disease caused by Vibrio cholerae of the O1 or O139 serogroups. In the past two centuries, cholera has emerged and spread from the Ganges Delta six times and from Indonesia once to cause global pandemics. Rational approaches to the case management of cholera with oral and intravenous rehydration therapy have reduced the case fatality of cholera from more than 50% to much less than 1%. Despite improvements in water quality, sanitation, and hygiene, as well as in the clinical treatment of cholera, the disease is still estimated to cause about 100 000 deaths every year. Most deaths occur in cholera-endemic settings, and virtually all deaths occur in developing countries. Contemporary understanding of immune protection against cholera, which results from local intestinal immunity, has yielded safe and protective orally administered cholera vaccines that are now globally stockpiled for use in the control of both epidemic and endemic cholera.
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Affiliation(s)
- John D Clemens
- International Centre for Diarrhoeal Disease Research, Bangladesh, Centre for Health and Population Research, Dhaka, Bangladesh; UCLA Fielding School of Public Health, Los Angeles, CA, USA; Korea University School of Medicine, Seoul, Korea.
| | | | - Tahmeed Ahmed
- International Centre for Diarrhoeal Disease Research, Bangladesh, Centre for Health and Population Research, Dhaka, Bangladesh
| | - Firdausi Qadri
- International Centre for Diarrhoeal Disease Research, Bangladesh, Centre for Health and Population Research, Dhaka, Bangladesh
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Clyburne-Sherin AVP, Thurairajah P, Kapadia MZ, Sampson M, Chan WWY, Offringa M. Recommendations and evidence for reporting items in pediatric clinical trial protocols and reports: two systematic reviews. Trials 2015; 16:417. [PMID: 26385379 PMCID: PMC4574457 DOI: 10.1186/s13063-015-0954-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 09/11/2015] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Complete and transparent reporting of clinical trial protocols and reports ensures that these documents are useful to all stakeholders, that bias is minimized, and that the research is not wasted. However, current studies repeatedly conclude that pediatric trial protocols and reports are not appropriately reported. Guidelines like SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) and CONSORT (Consolidated Standards of Reporting Trials) may improve reporting, but do not offer guidance on issues unique to pediatric trials. This paper reports two systematic reviews conducted to build the evidence base for the development of pediatric reporting guideline extensions: 1) SPIRIT-Children (SPIRIT-C) for pediatric trial protocols, and 2) CONSORT-Children (CONSORT-C) for pediatric trial reports. METHOD MEDLINE, the Cochrane Methodology Register, and reference lists of included studies were searched. Publications of any type were eligible if they included explicit recommendations or empirical evidence for the reporting of potential items in a pediatric protocol (SPIRIT-C systematic review) or trial report (CONSORT-C systematic review). Study characteristics, recommendations and evidence for pediatric extension items were extracted. Recurrent themes in the recommendations and evidence were identified and synthesized. All steps were conducted by two reviewers. RESULTS For the SPIRIT-C and CONSORT-C systematic reviews 366 and 429 publications were included, respectively. Recommendations were identified for 48 of 50 original reporting items and sub-items from SPIRIT, 15 of 20 potential SPIRIT-C reporting items, all 37 original CONSORT items and sub-items, and 16 of 22 potential CONSORT-C reporting items. The following overarching themes of evidence to support or refute the utility of reporting items were identified: transparency; reproducibility; interpretability; usefulness; internal validity; external validity; reporting bias; publication bias; accountability; scientific soundness; and research ethics. CONCLUSION These systematic reviews are the first to systematically gather evidence and recommendations for the reporting of specific items in pediatric protocols and trials. They provide useful and translatable evidence on which to build pediatric extensions to the SPIRIT and CONSORT reporting guidelines. The resulting SPIRIT-C and CONSORT-C will provide guidance to the authors of pediatric protocols and reports, respectively, helping to alleviate concerns of inappropriate and inconsistent reporting, and reduce research waste.
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Affiliation(s)
- April V P Clyburne-Sherin
- The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, SickKids Research Institute, Child Health Evaluative Sciences, 686 Bay Street, Toronto, ON, M5G 0A4, Canada.
| | - Pravheen Thurairajah
- The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, SickKids Research Institute, Child Health Evaluative Sciences, 686 Bay Street, Toronto, ON, M5G 0A4, Canada.
| | - Mufiza Z Kapadia
- The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, SickKids Research Institute, Child Health Evaluative Sciences, 686 Bay Street, Toronto, ON, M5G 0A4, Canada.
| | - Margaret Sampson
- Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, ON, K1H 8L1, Canada.
| | - Winnie W Y Chan
- The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, SickKids Research Institute, Child Health Evaluative Sciences, 686 Bay Street, Toronto, ON, M5G 0A4, Canada.
| | - Martin Offringa
- The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, SickKids Research Institute, Child Health Evaluative Sciences, 686 Bay Street, Toronto, ON, M5G 0A4, Canada. .,Senior Scientist and Program Head Child Health Evaluative Sciences, The Hospital for Sick Children, Peter Gilgan Centre for Research and Learning, SickKids Research Institute, 686 Bay Street, Toronto, ON, M5G 0A4, Canada.
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Mahmud ZH, Islam S, Zaman RU, Akter M, Talukder KA, Bardhan PK, Khan AI, Rhodes FC, Kamara A, Wurie IM, Alemu W, Jambai A, Faruque SM, Clemens JD, Islam MS. Phenotypic and genotypic characteristics of Vibrio cholerae O1 isolated from the Sierra Leone cholera outbreak in 2012. Trans R Soc Trop Med Hyg 2014; 108:715-20. [PMID: 25233936 DOI: 10.1093/trstmh/tru137] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND This study describes phenotypic, genotypic and antibiotic susceptibility patterns of the strains isolated from the 2012 Sierra Leone cholera outbreak. Rectal swabs were collected from patients and cultured for Vibrio cholerae O1. METHODS The isolates were subjected to multiplex PCR, mismatch amplification mutation assay (MAMA) PCR, pulsed field gel electrophoresis (PFGE), and antibiotic sensitivity tests using disk diffusion and minimum inhibitory concentration (MIC) E-test following standard procedures. RESULTS Out of 17 rectal swabs tested, 15 yielded V. cholerae O1 biotype El Tor, serotype Ogawa. All the strains belonged to 'altered' variants as MAMA PCR result showed the presence of classical cholera toxin B. PFGE result revealed four pulse types. Using antibiotic disk diffusion, all the isolates were resistant to erythromycin, chloramphenicol, furazolidone, and trimethoprim/sulfamethoxazole (SXT) except SL1 which was sensitive to chloramphenicol and SXT. All the isolates were sensitive to nalidixic acid, tetracycline, doxycycline, azithromycin, and ciprofloxacin except SL2 which was resistant to nalidixic acid. However, variable sensitivity patterns were observed for kanamycin. The ranges of MIC were 0.125-0.50 mg/l, 0.003-0.023 mg/l and 0.38-0.75 mg/l for azithromycin, ciprofloxacin and tetracycline, respectively. CONCLUSIONS This study demonstrates that altered variants of V. cholerae O1 of four clonal types were responsible for the 2012 outbreak of cholera in Sierra Leone.
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Affiliation(s)
- Zahid H Mahmud
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Shafiqul Islam
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Rokon U Zaman
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Mahmuda Akter
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Kaisar A Talukder
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Pradip K Bardhan
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Azharul I Khan
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Faye C Rhodes
- Central Public Health Reference Laboratory, Ministry of Health and Sanitation, Connaught Hospital, Free Town, Sierra Leone
| | - Abdul Kamara
- Central Public Health Reference Laboratory, Ministry of Health and Sanitation, Connaught Hospital, Free Town, Sierra Leone
| | - Isatta M Wurie
- World Health Organization, 21A and B Riverside Drive, off King Harman Road, Freetown, Sierra Leone
| | - Wondimagegnehu Alemu
- World Health Organization, 21A and B Riverside Drive, off King Harman Road, Freetown, Sierra Leone
| | - Amara Jambai
- Central Public Health Reference Laboratory, Ministry of Health and Sanitation, Connaught Hospital, Free Town, Sierra Leone
| | - Shah M Faruque
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - John D Clemens
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
| | - Mohammad S Islam
- International Centre for Diarrhoeal Disease Research, Bangladesh, 68 Shaheed Tajuddin Ahmed Sarani, Mohakhali, Dhaka 1212, Bangladesh
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Wagner A, Wiedermann U. Travellers' diarrhoea - pros and cons of different prophylactic measures. Wien Klin Wochenschr 2010; 121 Suppl 3:13-8. [PMID: 19915810 DOI: 10.1007/s00508-009-1228-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Travellers' diarrhoea is the most likely cause for disturbing travel arrangements. At an average, 30-40% of tourists are concerned, depending on the travel destination. Due to the high impact on the travellers' health this topic is still of utmost importance in travel medicine. A wide spectrum of enteropathogens can be accountable, with enterotoxigenic Escherichia coli being the major causing pathogen among other bacteria, parasites and viruses. Here we discuss advantages and disadvantages of different prophylactic measures against travellers' diarrhoea. The effectiveness but also the relevance of hygiene education, vaccination and antibiotic or probiotic application will be discussed in the context of the travellers' different risk profiles.
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Affiliation(s)
- Angelika Wagner
- Institute of Specific Prophylaxis and Tropical Medicine, Medical University Vienna, Vienna, Austria
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Shamsuzzaman S, Ahmed T, Mannoor K, Begum YA, Bardhan PK, Sack RB, Sack DA, Svennerholm AM, Holmgren J, Qadri F. Robust gut associated vaccine-specific antibody-secreting cell responses are detected at the mucosal surface of Bangladeshi subjects after immunization with an oral killed bivalent V. cholerae O1/O139 whole cell cholera vaccine: Comparison with other mucosal and systemic responses. Vaccine 2009; 27:1386-92. [DOI: 10.1016/j.vaccine.2008.12.041] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2008] [Revised: 12/05/2008] [Accepted: 12/20/2008] [Indexed: 12/29/2022]
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Longini IM, Nizam A, Ali M, Yunus M, Shenvi N, Clemens JD. Controlling endemic cholera with oral vaccines. PLoS Med 2007; 4:e336. [PMID: 18044983 PMCID: PMC2082648 DOI: 10.1371/journal.pmed.0040336] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Accepted: 10/15/2007] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND Although advances in rehydration therapy have made cholera a treatable disease with low case-fatality in settings with appropriate medical care, cholera continues to impose considerable mortality in the world's most impoverished populations. Internationally licensed, killed whole-cell based oral cholera vaccines (OCVs) have been available for over a decade, but have not been used for the control of cholera. Recently, these vaccines were shown to confer significant levels of herd protection, suggesting that the protective potential of these vaccines has been underestimated and that these vaccines may be highly effective in cholera control when deployed in mass immunization programs. We used a large-scale stochastic simulation model to investigate the possibility of controlling endemic cholera with OCVs. METHODS AND FINDINGS We construct a large-scale, stochastic cholera transmission model of Matlab, Bangladesh. We find that cholera transmission could be controlled in endemic areas with 50% coverage with OCVs. At this level of coverage, the model predicts that there would be an 89% (95% confidence interval [CI] 72%-98%) reduction in cholera cases among the unvaccinated, and a 93% (95% CI 82%-99%) reduction overall in the entire population. Even a more modest coverage of 30% would result in a 76% (95% CI 44%-95%) reduction in cholera incidence for the population area covered. For populations that have less natural immunity than the population of Matlab, 70% coverage would probably be necessary for cholera control, i.e., an annual incidence rate of < or = 1 case per 1,000 people in the population. CONCLUSIONS Endemic cholera could be reduced to an annual incidence rate of < or = 1 case per 1,000 people in endemic areas with biennial vaccination with OCVs if coverage could reach 50%-70% depending on the level of prior immunity in the population. These vaccination efforts could be targeted with careful use of ecological data.
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Affiliation(s)
- Ira M Longini
- Vaccine and Infectious Disease Institute, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America.
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Longini IM, Halloran ME, Nizam A. Model-based estimation of vaccine effects from community vaccine trials. Stat Med 2002; 21:481-95. [PMID: 11836731 DOI: 10.1002/sim.994] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Community vaccine trials are becoming increasingly important to assess both the direct and indirect community level effects of vaccination. In this paper, we present statistical methods to analyse such trials, using a design with several matched pairs of communities. The communities are matched on similarities in infection transmission as reflected through the basic reproduction number. Two methods of analysis are presented and compared. The first is simple empirical estimation of vaccine effects. Summary measures of these effects are constructed by reciprocal variance weighted averages across the community pairs. The second is likelihood-based where we derive a mixed effects epidemic model. This model takes the intercommunity variability into account through a random effect on the basic reproduction number. With this model, we derive a distribution-free estimator for the variance of the random effect. We use simulated epidemics to explore the performance of the two estimation methods for different numbers of community pairs and different levels of inter-pair variability. Both methods provide acceptable estimates in terms of bias and precision under reasonable conditions. Although the empirical approach involves fewer assumptions than the model-based approach, the resulting vaccine effectiveness estimates are only applicable to the vaccination fraction tested in the trial. In contrast, the model-based approach can be used to predict the vaccine effectiveness at vaccination fractions other than those used in the trial. Thus, it can be used as a public health policy tool for predicting the community level effects of vaccination. We demonstrate such use by predicting total vaccine effectiveness for the whole range of vaccination fractions.
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Affiliation(s)
- Ira M Longini
- Department of Biostatistics, Rollins School of Public Health, Emory University, 1518 Clifton Road, N.E., Atlanta, GA 30322, USA.
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Lagos R, Levine OS, Avendaño A, Horwitz I, Levine MM. The introduction of routine Haemophilus influenzae type b conjugate vaccine in Chile: a framework for evaluating new vaccines in newly industrializing countries. Pediatr Infect Dis J 1998; 17:S139-48. [PMID: 9781748 DOI: 10.1097/00006454-199809001-00010] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To determine the burden of Haemophilus influenzae type b (Hib) disease, the safety and immunogenicity of Hib conjugate vaccine, the practicality of combining Hib conjugate and diphtheria-tetanus-pertussis vaccines and the effectiveness of routine vaccination. STUDY DESIGNS A series of studies were carried out involving infants and children in Santiago, Chile. The study designs included retrospective surveillance, cost-benefit analysis, randomized placebo-controlled trials of safety and immunogenicity and a Phase IV postlicensure evaluation of vaccine effectiveness. RESULTS The studies included in this stepwise process showed that Hib invasive disease was a significant public health problem with a substantial economic burden; that combining Hib conjugate and diphtheria-tetanus-pertussis vaccines was practical, safe and elicited a strong immunologic response; and that the combined formulation afforded a high level of protection against invasive Hib disease (90% effectiveness). CONCLUSIONS In July, 1996, Chile became only the third newly industrializing country to introduce routine Hib conjugate vaccination. New vaccines, such as Hib conjugates, will be more expensive than existing ones. The stepwise process used in Chile may serve as an example for the evaluation of new vaccines in nonindustrialized countries.
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Affiliation(s)
- R Lagos
- Centro para Vacunas en Desarrollo, Servicio de Salud Metropolitano Norte, Santiago, Chile
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Rappuoli R, Pizza M. Novel molecular biology approaches to acellular vaccines. BIOTECHNOLOGY ANNUAL REVIEW 1998; 2:391-408. [PMID: 9704103 DOI: 10.1016/s1387-2656(08)70018-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Bacterial toxins are commonly detoxified by chemical treatment in order to use them in human vaccines. We have used site-directed mutagenesis of toxin genes to obtain bacteria that produce naturally nontoxic mutants of bacterial toxins, such as pertussis toxin (PT), cholera toxin (CT) and Escherichia coli heat-labile enterotoxin (LT). Genetically detoxified PT showed a superior safety and immunogenicity in animal models, phase I and phase II clinical trials, and a superior protective efficacy in the early and late stage of a phase III efficacy trial, proving in a definitive and extensive way that genetic detoxification of bacterial toxins can, and should, replace chemical treatment. The results obtained with genetically inactivated LT and CT indicate that genetic detoxification of bacterial toxins can be used not only to produce vaccines for systemic immunization that are superior to the ones produced by conventional technologies, but suggest that these type of molecules may be the prototype molecules for the design and construction of innovative vaccines with a totally new design, such as mucosally delivered preventive and therapeutic vaccines.
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Affiliation(s)
- R Rappuoli
- IRIS, Chiron Biocine Immunobiological Research Institute Siena, Italy
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van Loon FP, Clemens JD, Chakraborty J, Rao MR, Kay BA, Sack DA, Yunus M, Ali M, Svennerholm AM, Holmgren J. Field trial of inactivated oral cholera vaccines in Bangladesh: results from 5 years of follow-up. Vaccine 1996; 14:162-6. [PMID: 8852414 DOI: 10.1016/0264-410x(95)00122-h] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
To determine the protective efficacy (PE) of three doses of oral B subunit-killed whole cell (BS-WC) or killed whole cell-only (WC) vaccines against cholera, a clinical trial was conducted among 62285 children over 2 years and adult women in rural Bangladesh. During 5 years of follow-up, there were 144 cases of cholera in the BS-WC group (PE = 49%; P < 0.001), 150 in the WC group (PE = 47%; P < 0.001), and 283 in the K12 group. Protection by each vaccine was evident only during the first three years of follow-up; long-term protection of young children was observed only against classical but not El Tor cholera; 3-year protection against both cholera biotypes occurred among older persons, but at a higher level against classical cholera.
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Affiliation(s)
- F P van Loon
- International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
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Pizza M, Fontana MR, Giuliani MM, Domenighini M, Magagnoli C, Giannelli V, Nucci D, Hol W, Manetti R, Rappuoli R. A genetically detoxified derivative of heat-labile Escherichia coli enterotoxin induces neutralizing antibodies against the A subunit. J Exp Med 1994; 180:2147-53. [PMID: 7964489 PMCID: PMC2191794 DOI: 10.1084/jem.180.6.2147] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Escherichia coli enterotoxin (LT) and the homologous cholera toxin (CT) are A-B toxins that cause travelers' diarrhea and cholera, respectively. So far, experimental live and killed vaccines against these diseases have been developed using only the nontoxic B portion of these toxins. The enzymatically active A subunit has not been used because it is responsible for the toxicity and it is reported to induce a negligible titer of toxin neutralizing antibodies. We used site-directed mutagenesis to inactivate the ADP-ribosyltransferase activity of the A subunit and obtained nontoxic derivatives of LT that elicited a good titer of neutralizing antibodies recognizing the A subunit. These LT mutants and equivalent mutants of CT may be used to improve live and killed vaccines against cholera and enterotoxinogenic E. coli.
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Affiliation(s)
- M Pizza
- Immunobiological Research Institute Siena (IRIS), Italy
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