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Jongdeepaisal M, Inthasone S, Khonputsa P, Malaphone V, Pongsoipetch K, Pongvongsa T, Mayxay M, Chindavongsa K, Pell C, Maude RJ. Forest malaria and prospects for anti-malarial chemoprophylaxis among forest goers: findings from a qualitative study in Lao PDR. Malar J 2022; 21:8. [PMID: 34983549 PMCID: PMC8727080 DOI: 10.1186/s12936-021-04027-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 12/16/2021] [Indexed: 11/15/2022] Open
Abstract
Background Despite significant decline in malarial incidence and mortality in countries across the Greater Mekong Subregion, the disease remains a public health challenge in the region; transmission continues mainly among people who visit forests in remote areas, often along international borders, where access to primary healthcare is limited. In the absence of effective vector-control measures and limited exposure periods, malaria chemoprophylaxis has been proposed as a strategy to protect forest goers. As a rarely used approach for indigenous populations, questions remain about its feasibility and acceptability. Drawing on in-depth interviews with forest goers and stakeholders, this article examines opportunities and challenges for implementation of anti-malarial chemoprophylaxis for forest goers in Lao PDR. Methods In-depth interviews were conducted with 16 forest goers and 15 stakeholders in Savannakhet province, Lao PDR. Interview topics included experience of malaria prevention and health services, and perceptions of prophylaxis as a potential component of malaria elimination strategy. The interviews were transcribed and coded using inductive and deductive approaches for qualitative thematic analysis. Results In ethnically and geographically diverse villages, awareness of malaria risk prompts forest goers to protect themselves, albeit sub-optimally using available preventive measures. Stakeholders highlighted challenges for targeting at-risk populations and approaches to address forest malaria in southern Lao PDR. Among policymakers, choice and cost of anti-malarials, particularly their efficacy and source of funding, were key considerations for the feasibility of malaria prophylaxis. Acceptability of prophylaxis among forest goers was also influenced by the complexity of the regimen, including the number of tablets and timing of doses. Implementation of prophylaxis may be affected by a lack of transportation and communication barriers in remote communities. Conclusion Adding prophylaxis to existing malaria control activities requires strengthening the capacity of local health workers in Lao PDR. Ideally, this would be part of an integrated approach that includes strategies to address the other febrile illnesses that forest goers describe as priority health concerns. The prophylactic regimen also requires careful consideration in terms of effectiveness and simplicity of dosing. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-04027-z.
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Affiliation(s)
- Monnaphat Jongdeepaisal
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Soulixay Inthasone
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Panarasri Khonputsa
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Vilayvone Malaphone
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Kulchada Pongsoipetch
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Mayfong Mayxay
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.,Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Mahosot Hospital, Ministry of Health, Vientiane, Lao PDR.,Institute of Research and Education Development (IRED), University of Health Sciences, Ministry of Health, Vientiane, Lao PDR
| | | | - Christopher Pell
- Amsterdam Institute for Global Health and Development (AIGHD), Amsterdam, The Netherlands.,Department of Global Health, Amsterdam University Medical Centers, Amsterdam, The Netherlands.,Centre for Social Science and Global Health, University of Amsterdam, Amsterdam, The Netherlands
| | - Richard J Maude
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. .,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK. .,Harvard TH Chan School of Public Health, Harvard University, Boston, USA. .,The Open University, Milton Keynes, UK.
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Abstract
The development of an effective malaria vaccine represents one of the most important approaches that would provide a cost-effective intervention for addition to currently available malaria control strategies. Here, Howard Engers and Tore Godal review recent advances. Over the past decade there has been considerable progress in the understanding of immune mechanisms involved in conferring protection to malaria and in the identification of vaccine candidate antigens and their genes. Several new vaccines have entered Phase I/II trials recently, new adjuvants have been developed for human use and new approaches, such as DNA vaccines and structural modification of antigens to circumvent some of the strategies the parasite uses to avoid the immune response, are being applied. Thus, from the TDR perspective, global malaria vaccine development is entering a crucial period with unprecedented opportunities.
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3
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Dubovsky F, Malkin E. Malaria vaccines. Vaccines (Basel) 2008. [DOI: 10.1016/b978-1-4160-3611-1.50056-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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4
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Abstract
BACKGROUND Four types of malaria vaccine, SPf66 and MSP/RESA vaccines (against the asexual stages of the Plasmodium parasite) and CS-NANP and RTS,S vaccines (against the sporozoite stages), have been tested in randomized controlled trials in endemic areas. OBJECTIVES To assess malaria vaccines against Plasmodium falciparum, P. vivax, P. malariae and P ovale in preventing infection, disease and death. SEARCH STRATEGY We searched the Cochrane Infectious Diseases Group Specialized Register (April 2004), CENTRAL (The Cochrane Library Issue 2, 2004), MEDLINE (1966 to April 2004), EMBASE (1980 to April 2004), Science Citation Index (1981 to April 2004), and reference lists of articles. We also contacted organizations and researchers in the field. SELECTION CRITERIA Randomized controlled trials comparing vaccines against Plasmodium falciparum, P. vivax, P. malariae or P. ovale with placebo or routine antimalarial control measures in people of any age receiving a challenge malaria infection. DATA COLLECTION AND ANALYSIS Two reviewers independently assessed trial quality and extracted data. MAIN RESULTS Eighteen efficacy trials involving 10,971 participants were included. There were ten trials of SPf66 vaccine, four trials of CS-NANP vaccines, two trials of RTS,S vaccine, and two of MSP/RESA vaccine. Results with SPf66 in reducing new malaria infections (P. falciparum) were heterogeneous: it was not effective in four African trials (Peto odds ratio (OR) 0.96, 95% confidence interval (CI) 0.81 to 1.14), but in five trials outside Africa the number of first attacks was reduced (Peto OR 0.77, 95% CI 0.67 to 0.88). Trials to date have not indicated any serious adverse events with SPf66 vaccine. In three trials of CS-NANP vaccines, there was no evidence for protection by these vaccines against P. falciparum malaria (Peto OR 1.12, 95% CI 0.64 to 1.93). In a small trial in non-immune adults in the USA, RTS,S gave strong protection against experimental infection with P. falciparum. In a trial in an endemic area of the Gambia in semi-immune people, there was a reduction in clinical malaria episodes in the second year of follow up, corresponding to a vaccine efficacy of 66% (CI 14% to 85%). In a trial in Papua New Guinea, MSP/RESA had no protective effect against episodes of clinical malaria. There was evidence of an effect on parasite density, but this differed according to whether the participants had been pretreated with sulfadoxine/pyrimethamine or not. The prevalence of infections with the parasite subtype of MSP2 in the vaccine was reduced compared with the other subtype (Peto OR 0.35, CI 0.23 to 0.53). AUTHORS' CONCLUSIONS There is no evidence for protection by SPf66 vaccines against P. falciparum in Africa. There is a modest reduction in attacks of P. falciparum malaria following vaccination with SPf66 in other regions. Further research with SPf66 vaccines in South America or with new formulations of SPf66 may be justified. There was not enough evidence to evaluate the use of CS-NANP vaccines. The RTS,S vaccine showed promising result, as did the MSP/RESA vaccine, but it should include the other main allelic form of MSP2. The MSP/RESA trial demonstrated that chemotherapy during a vaccine trial may reduce vaccine efficacy, and trials should consider very carefully whether this practice is justified.
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Affiliation(s)
- P Graves
- EpiVec Consulting, 606 Kimberly Lane NE, Atlanta, GA 30306, USA.
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5
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Abstract
BACKGROUND A malaria vaccine is badly needed. SPf66 was one of the earliest vaccines developed. It is a synthetic peptide vaccine containing antigens from the blood stages of malaria linked together with an antigen from the sporozoite stage, and is targeted mainly against the blood (asexual) stages. OBJECTIVES To assess the effect of SPf66 malaria vaccines against Plasmodium falciparum, P. vivax, P. malariae, and P. ovale in preventing infection, disease, and death. SEARCH STRATEGY We searched the Cochrane Infectious Diseases Group Specialized Register (September 2005), CENTRAL (The Cochrane Library 2005, Issue 3), MEDLINE (1966 to September 2005), EMBASE (1980 to September 2005), LILACS (1982 to September 2005), Science Citation Index (1981 to September 2005), and reference lists of articles. We also contacted organizations and researchers in the field. SELECTION CRITERIA Randomized and quasi-randomized controlled trials comparing SPf66 vaccine with placebo or routine antimalarial control measures in people of any age receiving an artificial challenge or natural exposure to malaria infection (any species). DATA COLLECTION AND ANALYSIS Two people independently assessed trial quality and extracted data, including adverse events. Results were expressed as relative risks (RR) with 95% confidence intervals (CI). MAIN RESULTS Ten efficacy trials of SPf66 involving 9698 participants were included. Results with SPf66 in reducing new episodes of P. falciparum malaria were heterogeneous: it was not effective in four African trials (RR 0.98, 95% CI 0.90 to 1.07; 2371 participants) or in one Asian trial (RR 1.06, 95% CI 0.90 to 1.25; 1221 participants). In four trials in South America the number of first attacks with P. falciparum was reduced by 28% (RR 0.72, 95% CI 0.63 to 0.82; 3807 participants). It did not reduce episodes of P. vivax malaria or admission to hospital with severe malaria. Trials have not indicated any serious adverse events with SPf66 vaccine. AUTHORS' CONCLUSIONS There is no evidence for protection by SPf66 vaccines against P. falciparum in Africa. There is a modest reduction in attacks of P. falciparum malaria following vaccination with SPf66 in South America. There is no justification for further trials of SPf66 in its current formulation. Further research with SPf66 vaccines in South America or with new formulations of SPf66 may be justified.
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Affiliation(s)
- P Graves
- Centers for Diseases Control and Prevention, Division of Parasitic Diseases, Mailstop F42, Building 102, Room 2113, 4770 Burford Highway NE, Atlanta, GA 30306, USA.
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6
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Abstract
BACKGROUND Four types of malaria vaccine, SPf66 and MSP/RESA vaccines (against the asexual stages of the Plasmodium parasite) and CS-NANP and RTS,S vaccines (against the sporozoite stages), have been tested in randomized controlled trials in endemic areas. OBJECTIVES To assess malaria vaccines against Plasmodium falciparum, P. vivax, P. malariae and P ovale in preventing infection, disease and death. SEARCH STRATEGY We searched the Cochrane Infectious Diseases Group trials register (July 2002), the Cochrane Controlled Trials Register (The Cochrane Library Issue 2, 2002), MEDLINE (1966 to July 2002), EMBASE (1980 to May 2002), Science Citation Index (1981 to July 2002), and reference lists of articles. We also contacted organizations and researchers in the field. SELECTION CRITERIA Randomized controlled trials comparing vaccines against Plasmodium falciparum, P. vivax, P. malariae or P. ovale with placebo or routine antimalarial control measures in people of any age receiving a challenge malaria infection. DATA COLLECTION AND ANALYSIS Two reviewers independently assessed trial quality and extracted data. MAIN RESULTS Eighteen efficacy trials involving 10,971 participants were included. There were ten trials of SPf66 vaccine, four trials of CS-NANP vaccines, two trials of RTS,S vaccine, and two of MSP/RESA vaccine. Results with SPf66 in reducing new malaria infections (P. falciparum) were heterogeneous: it was not effective in four African trials (Peto odds ratio (OR) 0.96, 95% confidence interval (CI) 0.81 to 1.14), but in five trials outside Africa the number of first attacks was reduced (Peto OR 0.77, 95% CI 0.67 to 0.88). Trials to date have not indicated any serious adverse events with SPf66 vaccine. In three trials of CS-NANP vaccines, there was no evidence for protection by these vaccines against P. falciparum malaria (Peto OR 1.12, 95% CI 0.64 to 1.93). In a small trial in non-immune adults in the USA, RTS,S gave strong protection against experimental infection with P. falciparum. In a trial in an endemic area of the Gambia in semi-immune people, there was a reduction in clinical malaria episodes in the second year of follow up, corresponding to a vaccine efficacy of 66% (CI 14% to 85%). In a trial in Papua New Guinea, MSP/RESA had no protective effect against episodes of clinical malaria. There was evidence of an effect on parasite density, but this differed according to whether the participants had been pretreated with sulfadoxine/pyrimethamine or not. The prevalence of infections with the parasite subtype of MSP2 in the vaccine was reduced compared with the other subtype (Peto OR 0.35, CI 0.23 to 0.53). REVIEWER'S CONCLUSIONS There is no evidence for protection by SPf66 vaccines against P. falciparum in Africa. There is a modest reduction in attacks of P. falciparum malaria following vaccination with SPf66 in other regions. Further research with SPf66 vaccines in South America or with new formulations of SPf66 may be justified. There was not enough evidence to evaluate the use of CS-NANP vaccines. The RTS,S vaccine showed promising result, as did the MSP/RESA vaccine, but it should include the other main allelic form of MSP2. The MSP/RESA trial demonstrated that chemotherapy during a vaccine trial may reduce vaccine efficacy, and trials should consider very carefully whether this practice is justified.
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Affiliation(s)
- P Graves
- 1400 W. Oak Street, Fort Collins, CO 80521, USA.
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7
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Schneider J, Langermans JA, Gilbert SC, Blanchard TJ, Twigg S, Naitza S, Hannan CM, Aidoo M, Crisanti A, Robson KJ, Smith GL, Hill AV, Thomas AW. A prime-boost immunisation regimen using DNA followed by recombinant modified vaccinia virus Ankara induces strong cellular immune responses against the Plasmodium falciparum TRAP antigen in chimpanzees. Vaccine 2001; 19:4595-602. [PMID: 11535306 DOI: 10.1016/s0264-410x(01)00260-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Two chimpanzees were vaccinated intramuscularly against malaria using plasmid DNA expressing the pre-erythrocytic antigens thrombospondin related adhesion protein (PfTRAP) and liver stage specific antigen-1 (PfLSA-1) of Plasmodium falciparum together with GM-CSF protein. A recombinant modified vaccinia virus Ankara (MVA) expressing PfTRAP was injected intramuscularly 6 weeks later to boost the immune response. This sequence of antigen delivery induced a specific and long-lasting T cell and antibody response to PfTRAP as detected by ELISPOT assay and ELISA. Antibody responses were detected after four DNA injections, and were boosted by injection of recombinant MVA expressing PfTRAP. Interferon-gamma secreting antigen-specific T cells were detected in both animals, but only after boosting with recombinant MVA. By screening a panel of PfTRAP-derived peptides, an epitope was identified that was recognized by cytotoxic T lymphocytes in one of the chimpanzees studied. T cells specific for this epitope were present in PBMCs and liver-infiltrating lymphocytes at a frequency of between 1 in 200 and 1 in 500. The high immunogenicity of this prime-boost regimen in chimpanzees supports further assessment of this delivery strategy for the induction of protection against P. falciparum malaria in humans.
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MESH Headings
- Animals
- Antibodies, Protozoan/biosynthesis
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- COS Cells
- Chick Embryo
- Chlorocebus aethiops
- DNA, Protozoan/genetics
- Enzyme-Linked Immunosorbent Assay
- Epitopes/immunology
- Fibroblasts/virology
- Genetic Vectors/genetics
- Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology
- Humans
- Immunity, Cellular
- Immunization Schedule
- Immunization, Secondary
- Leukocytes, Mononuclear/immunology
- Malaria Vaccines/administration & dosage
- Malaria Vaccines/immunology
- Male
- Pan troglodytes
- Plasmodium falciparum/immunology
- Protozoan Proteins/genetics
- Protozoan Proteins/immunology
- Recombinant Proteins/pharmacology
- T-Lymphocytes, Cytotoxic/immunology
- Transfection
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/immunology
- Vaccinia virus/genetics
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Affiliation(s)
- J Schneider
- Molecular Immunology Group, Institute of Molecular Medicine, Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital, OX3 9DU, Oxford, UK.
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8
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Peduzzi P, Donta S, Iwane M. A review of the design of vaccine efficacy trials and a proposal for the design of the VA Cooperative Study of Active Immunotherapy of HIV Infection. CONTROLLED CLINICAL TRIALS 1997; 18:397-419. [PMID: 9315424 DOI: 10.1016/s0197-2456(97)00026-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We review the design of vaccine trials based on a search of the medical literature over the past four years, and present the proposed design of a therapeutic HIV vaccine efficacy study by the Department of Veterans Affairs Cooperative Studies Program. We explore the reasons for the atypical design of many vaccine trials, particularly the analysis of efficacy and how it differs from the more usual intent-to-treat analysis used in nonvaccine trials.
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Affiliation(s)
- P Peduzzi
- Cooperative Studies Program, VA Medical Center, West Haven, CT 06516, USA
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Migasena S, Heppner DG, Kyle DE, Chongsuphajaisiddhi T, Gordon DM, Suntharasamai P, Permpanich B, Brockman A, Pitiuttutham P, Wongsrichanalai C, Srisuriya P, Phonrat B, Pavanand K, Viravan C, Ballou WR. SPf66 malaria vaccine is safe and immunogenic in malaria naive adults in Thailand. Acta Trop 1997; 67:215-27. [PMID: 9241386 DOI: 10.1016/s0001-706x(97)00061-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In preparation for an efficacy trial of malaria vaccine SPf66 in Thailand, a series of overlapping Phase I trials were conducted of US-manufactured SPf66. Here, two clinical lots were evaluated for safety and immunogenicity in a combined open-label trial. Eleven healthy, malaria naive, 18-44 year-old Thai men and women received three doses by subcutaneous injection in alternate arms at 0, 1 and 6 months. Safety was assessed by monitoring local and systemic reactogenicity and laboratory parameters. Common side effects were mild erythema, induration and tenderness at the site of injection which resolved within 24-48 h. At third immunization, two volunteers developed acute bilateral reactions with induration, erythema and pruritus limited to the sites of the second and third immunizations. Eight of 11 volunteers sero-converted by ELISA, six of whom would be classified as high responders by Colombian standards. Eight of 11 volunteers developed a lymphoproliferative response to the SPf66 antigen. Side effects were more common and antibody and lymphoproliferative responses greatest, among the four female volunteers. This initial study of SPf66 malaria vaccine in Asia constitutes an essential link between the initial Phase I study in the US and subsequent field studies in a semi-immune population in a malaria endemic area of Thailand. This study further establishes comparability of US-manufactured SPf66 with that of Colombian provenance and substantiates the validity of the subsequent negative efficacy results of SPf66 in a field trial in Thailand.
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Affiliation(s)
- S Migasena
- Vaccine Trial Center, Mahidol University, Thailand
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Abstract
Advances have been made in the development of vaccines based on synthetic peptides and polypeptides representing tumor-associated antigens and protective epitopes of viruses and parasites. Advances within the past year include the design of vaccines based on artificial proteins, for example multiantigen peptides, branched polypeptides, fusion and recombinant peptides, as well as single T cell epitopes and tumor antigen peptides. Although peptide vaccines are not in use as yet, their potential is being explored.
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Affiliation(s)
- T Ben-Yedidia
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
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11
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Facer CA, Tanner M. Clinical trials of malaria vaccines: progress and prospects. ADVANCES IN PARASITOLOGY 1997; 39:1-68. [PMID: 9241814 DOI: 10.1016/s0065-308x(08)60044-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- C A Facer
- Department of Haematology, St Bartholomew's and The Royal London School of Medicine and Dentistry, UK
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12
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Nosten F, Luxemburger C, Kyle DE, Ballou WR, Wittes J, Wah E, Chongsuphajaisiddhi T, Gordon DM, White NJ, Sadoff JC, Heppner DG. Randomised double-blind placebo-controlled trial of SPf66 malaria vaccine in children in northwestern Thailand. Shoklo SPf66 Malaria Vaccine Trial Group. Lancet 1996; 348:701-7. [PMID: 8806288 DOI: 10.1016/s0140-6736(96)04465-0] [Citation(s) in RCA: 109] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Previous efficacy trials of SPf66 malaria vaccine have produced conflicting results in different populations. We report a randomised double-blind trial of the SPf66 vaccine conducted in Karen children aged 2-15 living in a malarious region of northwestern Thailand. Recombinant hepatitis B vaccine was used as a comparator. METHODS The study had a power of 90% to detect an efficacy of 30%, defined as a reduction in the incidence of first cases of symptomatic falciparum malaria after three doses of vaccine. 1221 children received three immunisations and were eligible for the primary efficacy analysis. Intense active and passive case detection continued over 15 months of follow-up. FINDINGS The SPf66 vaccine was well tolerated, although 26 children had mild or moderately severe local or systemic allergic reactions, compared with none in the comparator group. The vaccine was immunogenic; after three doses, 73% of recipients had seroconverted. There were no deaths due to malaria during the study. During the 15-month period of evaluation there were 379 first cases of symptomatic falciparum malaria (195 in the SPf66 recipients, 184 in the comparator group); an SPf66 efficacy of -9% (95% CI -33 to 14, p = 0.41). No significant differences between the two study groups in parasite density or any other measure of malaria-related morbidity were detected. INTERPRETATION These findings are consistent with a recent study showing lack of efficacy of SPf66 among Gambian infants and differ from earlier positive reports from South America and evidence of borderline efficacy from Tanzania. We conclude that SPf66 does not protect against clinical falciparum malaria and that further efficacy trials are not warranted.
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Affiliation(s)
- F Nosten
- Shoklo Malaria Research Unit, Mae Sot, Thailand
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Bundy DA, Chan MS, Guyatt HL. The practicality and sustainability of vaccination as an approach to parasite control. Parasitology 1995; 110 Suppl:S51-8. [PMID: 7784130 DOI: 10.1017/s0031182000001499] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The development of a successful vaccine depends not only on the production of the vaccine itself, but also on the design pf the vaccination programme. This involves a better understanding of the epidemiology of the disease to be controlled, the delivery system to be used and the costs involved. This review focuses on current understanding of parasite population dynamics and epidemiology, and on the logistic experience gained from immunization programmes using existing viral and bacterial vaccines. The feasibility and sustainability of any new vaccine would greatly benefit from research into epidemiology and health systems which are conducted in parallel, rather than sequential to, vaccine development.
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Affiliation(s)
- D A Bundy
- Department of Zoology, University of Oxford
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