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Ewald S, Nasuhidehnavi A, Feng TY, Lesani M, McCall LI. The intersection of host in vivo metabolism and immune responses to infection with kinetoplastid and apicomplexan parasites. Microbiol Mol Biol Rev 2024; 88:e0016422. [PMID: 38299836 PMCID: PMC10966954 DOI: 10.1128/mmbr.00164-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2024] Open
Abstract
SUMMARYProtozoan parasite infection dramatically alters host metabolism, driven by immunological demand and parasite manipulation strategies. Immunometabolic checkpoints are often exploited by kinetoplastid and protozoan parasites to establish chronic infection, which can significantly impair host metabolic homeostasis. The recent growth of tools to analyze metabolism is expanding our understanding of these questions. Here, we review and contrast host metabolic alterations that occur in vivo during infection with Leishmania, trypanosomes, Toxoplasma, Plasmodium, and Cryptosporidium. Although genetically divergent, there are commonalities among these pathogens in terms of metabolic needs, induction of the type I immune responses required for clearance, and the potential for sustained host metabolic dysbiosis. Comparing these pathogens provides an opportunity to explore how transmission strategy, nutritional demand, and host cell and tissue tropism drive similarities and unique aspects in host response and infection outcome and to design new strategies to treat disease.
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Affiliation(s)
- Sarah Ewald
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Azadeh Nasuhidehnavi
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma, USA
| | - Tzu-Yu Feng
- Department of Microbiology, Immunology, and Cancer Biology at the Carter Immunology Center, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Mahbobeh Lesani
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
| | - Laura-Isobel McCall
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma, USA
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, Oklahoma, USA
- Laboratories of Molecular Anthropology and Microbiome Research, University of Oklahoma, Norman, Oklahoma, USA
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California, USA
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2
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Schnyder JL, de Jong HK, Bache BE, Schaumburg F, Grobusch MP. Long-term immunity following yellow fever vaccination: a systematic review and meta-analysis. Lancet Glob Health 2024; 12:e445-e456. [PMID: 38272044 DOI: 10.1016/s2214-109x(23)00556-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/20/2023] [Accepted: 11/24/2023] [Indexed: 01/27/2024]
Abstract
BACKGROUND Long-term immunity following yellow fever vaccination remains controversial. We aimed to summarise the literature regarding the long-term protection (≥10 years) conveyed by a single dose of yellow fever vaccination. METHODS In this systematic review and meta-analysis, we searched 11 databases from database inception to Aug 24, 2023. We included cohort and cross-sectional studies reporting immunogenicity outcomes for children or adults who received a single dose of yellow fever vaccination 10 or more years ago. Case series and single case reports were excluded. Participants who received more than one dose of yellow fever vaccination before measurement of the outcome were excluded. Identified records were reviewed by two independent reviewers. The primary outcome of the meta-analysis was the pooled seroprotection rate. Risk of bias was assessed with the Risk Of Bias In Non-randomized Studies of Interventions tool, and the Joanna Briggs Institute tool for analytical cross-sectional studies. Studies of moderate or good quality that reported seroprotection were included for random-effects meta-analysis and stratified by endemicity and specific risk groups. The study was registered with PROSPERO, CRD42023384087. FINDINGS Of the 7363 articles identified by our search, 39 were eligible for inclusion for systematic review. These studies comprised 2895 individuals vaccinated 10-60 years ago. 20 studies were included in the meta-analysis. Pooled seroprotection rates were 94% (95% CI 86-99) among healthy adults in a non-endemic setting (mostly travellers) and 76% (65-85) in an endemic setting (all Brazilian studies). The pooled seroprotection rate was 47% (35-60) in children (aged 9-23 months at time of vaccination) and 61% (38-82) in people living with HIV. Reported criteria for seroprotection were highly heterogeneous. INTERPRETATION The gathered evidence suggests that a single dose of yellow fever vaccination provides lifelong protection in travellers. However, in people living with HIV and children (younger than 2 years), booster doses might still be required because lower proportions of vaccinees were seroprotected 10 or more years post-vaccination. Lower observed seroprotection rates among residents of endemic areas were partly explained by the use of a higher cutoff for seroprotection that was applied in Brazil. Studies from sub-Saharan Africa were scarce and of low quality; thus no conclusions could be drawn for this region. FUNDING None.
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Affiliation(s)
- Jenny L Schnyder
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Hanna K de Jong
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Bache E Bache
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands; Masanga Medical Research Unit, Masanga, Sierra Leone
| | - Frieder Schaumburg
- Masanga Medical Research Unit, Masanga, Sierra Leone; Institute of Medical Microbiology, University Hospital Münster, Münster, Germany
| | - Martin P Grobusch
- Center for Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands; Masanga Medical Research Unit, Masanga, Sierra Leone; Institute of Tropical Medicine, German Centre for Infection Research, University of Tübingen, Tübingen, Germany; Centre de Recherches Médicales en Lambaréné, Lambaréné, Gabon; Institute of Infectious Diseases and Molecular Medicine, University of Cape Town, Cape Town, South Africa.
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3
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Kling K, Domingo C, Bogdan C, Mertens T, Wolff R, Wiedermann U. Comment on: “New recommendation on yellow fever booster vaccination in Germany”. Travel Med Infect Dis 2023; 52:102561. [PMID: 36967051 DOI: 10.1016/j.tmaid.2023.102561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/08/2023] [Accepted: 03/02/2023] [Indexed: 03/31/2023]
Affiliation(s)
- Kerstin Kling
- Immunization Unit, Department of Infectious Disease Epidemiology, Robert Koch Institute, Berlin, Germany.
| | - Cristina Domingo
- Center for International Health Protection, Robert Koch Institute, Berlin, Germany
| | - Christian Bogdan
- Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg and Universitätsklinikum Erlangen, Erlangen, Germany; Medical Immunology Campus Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Thomas Mertens
- Institut für Virologie, Universität Ulm und Universitätsklinikum, Ulm, Germany
| | - Robert Wolff
- Kleijnen Systematic Reviews Ltd, York, United Kingdom
| | - Ursula Wiedermann
- Institut für Spezifische Prophylaxe und Tropenmedizin, Medizinische Universität Wien, Wien, Austria
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4
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Staples JE, Barrett ADT, Wilder-Smith A, Hombach J. Review of data and knowledge gaps regarding yellow fever vaccine-induced immunity and duration of protection. NPJ Vaccines 2020; 5:54. [PMID: 32655896 PMCID: PMC7338446 DOI: 10.1038/s41541-020-0205-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Accepted: 05/29/2020] [Indexed: 12/13/2022] Open
Abstract
Yellow fever (YF) virus is a mosquito-borne flavivirus found in Sub-Saharan Africa and tropical South America. The virus causes YF, a viral hemorrhagic fever, which can be prevented by a live-attenuated vaccine, strain 17D. Despite the vaccine being very successful at decreasing disease risk, YF is considered a re-emerging disease due to the increased numbers of cases in the last 30 years. Until 2014, the vaccine was recommended to be administered with boosters every 10 years, but in 2014 the World Health Organization recommended removal of booster doses for all except special populations. This recommendation has been questioned and there have been reports of waning antibody titers in adults over time and more recently in pediatric populations. Clearly, the potential of waning antibody titers is a very important issue that needs to be carefully evaluated. In this Perspective, we review what is known about the correlate of protection for full-dose YF vaccine, current information on waning antibody titers, and gaps in knowledge. Overall, fundamental questions exist on the durability of protective immunity induced by YF vaccine, but interpretation of studies is complicated by the use of different assays and different cut-offs to measure seroprotective immunity, and differing results among certain endemic versus non-endemic populations. Notwithstanding the above, there are few well-characterized reports of vaccine failures, which one would expect to observe potentially more with the re-emergence of a severe disease. Overall, there is a need to improve YF disease surveillance, increase primary vaccination coverage rates in at-risk populations, and expand our understanding of the mechanism of protection of YF vaccine.
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Affiliation(s)
- J. Erin Staples
- Arboviral Diseases Branch, U.S. Centers for Disease Control and Prevention, Fort Collins, CO USA
| | - Alan D. T. Barrett
- Department of Pathology and Sealy Institute for Vaccine Sciences, University of Texas Medical Branch, Galveston, TX USA
| | - Annelies Wilder-Smith
- Institute of Public Health, University of Heidelberg, Heidelberg, Germany
- London School of Hygiene and Tropical Medicine, London, UK
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5
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Burkhard J, Ciurea A, Gabay C, Hasler P, Müller R, Niedrig M, Fehr J, Villiger P, Visser LG, de Visser AW, Walker UA, Hatz C, Bühler S. Long-term immunogenicity after yellow fever vaccination in immunosuppressed and healthy individuals. Vaccine 2020; 38:3610-3617. [PMID: 31911033 DOI: 10.1016/j.vaccine.2019.12.042] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 12/11/2019] [Accepted: 12/19/2019] [Indexed: 02/03/2023]
Abstract
BACKGROUND The live-attenuated yellow fever vaccine (YFV) is generally contraindicated in immunosuppressed patients. Our aim was to investigate if immunosuppressive therapy impairs the long-term protection against yellow fever virus in patients who had received YFV prior to the start of their immunosuppressive therapy. METHODS Our study examined 35 healthy individuals and 40 immunosuppressed patients with autoimmune diseases or organ transplants. All individuals had received YFV prior to the onset of their immunosuppression. We analysed the long-term influence of the immunosuppressive therapy on the YFV protective immunity by measuring neutralising antibodies (NA) with the Plaque Reduction Neutralisation Test (PRNT). We assessed risk factors for a negative PRNT result (titre below 1: 10) and their influence on the magnitude of the NA. RESULTS A median time interval of 21.1 years (interquartile range 14.4-31.3 years) after the YFV in all patients, a total of 35 immunosuppressed patients (88%) were seropositive (PRNT ≥ 1:10) compared to 31 patients (89%) in the control group. The geometric mean titres of NA did not differ between the groups. The duration of an underlying rheumatic disease was the only risk factor found for a lower magnitude of NA. An insufficient level of NA was found in nine subjects (12%) who had received a single dose of YFV (in one subject, the number of YFV doses was unknown). CONCLUSION The use of an immunosuppressive drug started after the administration of the YFV did not affect long-term persistence of NA. A second dose of YFV may be necessary to secure long-term immunity.
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Affiliation(s)
- J Burkhard
- Department of Public Health / Division of Infectious Diseases, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland
| | - A Ciurea
- Department of Rheumatology, University Hospital of Zurich, Zurich, Switzerland
| | - C Gabay
- Division of Rheumatology, University Hospital of Geneva, Geneva, Switzerland
| | - P Hasler
- Department of Rheumatology, Cantonal Hospital Aarau, Aarau, Switzerland
| | - R Müller
- Division of Rheumatology, Department of Internal Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland; Division of Rheumatology and Clinical Immunology, Department of Internal Medicine Ludwig-Maximilians-University Munich, Germany
| | - M Niedrig
- Robert Koch-Institut (RKI), Berlin, Germany
| | - J Fehr
- Department of Public Health / Division of Infectious Diseases, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland
| | - P Villiger
- Department of Rheumatology and Clinical Immunology/Allergology, University Hospital of Bern, Bern, Switzerland
| | - L G Visser
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - A W de Visser
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - U A Walker
- Department of Rheumatology, University Hospital Basel, Basel, Switzerland
| | - C Hatz
- Department of Public Health / Division of Infectious Diseases, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland; Department of Medicine and Diagnostics, Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Switzerland; Division of Infectious Diseases & Hospital Epidemiology, Kantonsspital St. Gallen, Switzerland
| | - S Bühler
- Department of Public Health / Division of Infectious Diseases, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland; Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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6
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Veit O, Domingo C, Niedrig M, Staehelin C, Sonderegger B, Héquet D, Stoeckle M, Calmy A, Schiffer V, Bernasconi E, Flury D, Hatz C, Zwahlen M, Furrer H. Long-term Immune Response to Yellow Fever Vaccination in Human Immunodeficiency Virus (HIV)-Infected Individuals Depends on HIV RNA Suppression Status: Implications for Vaccination Schedule. Clin Infect Dis 2019; 66:1099-1108. [PMID: 29140432 DOI: 10.1093/cid/cix960] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 11/07/2017] [Indexed: 11/12/2022] Open
Abstract
Background In human immunodeficiency virus (HIV)-infected individuals, the immune response over time to yellow fever vaccination (YFV) and the necessity for booster vaccination are not well understood. Methods We studied 247 participants of the Swiss HIV Cohort Study (SHCS) with a first YFV after HIV diagnosis and determined their immune responses at 1 year, 5 years, and 10 years postvaccination by yellow fever plaque reduction neutralization titers (PRNTs) in stored blood samples. A PRNT of 1:≥10 was regarded as reactive and protective. Predictors of vaccination response were analyzed with Poisson regression. Results At vaccination, 82% of the vaccinees were taking combination antiretroviral therapy (cART), 83% had suppressed HIV RNA levels (<400 copies/mL), and their median CD4 T-cell count was 536 cells/μL. PRNT was reactive in 46% (95% confidence interval [CI], 38%-53%) before, 95% (95% CI, 91%-98%) within 1 year, 86% (95% CI, 79%-92%) at 5 years, and 75% (95% CI, 62%-85%) at 10 years postvaccination. In those with suppressed plasma HIV RNA at YFV, the proportion with reactive PRNTs remained high: 99% (95% CI, 95%-99.8%) within 1 year, 99% (95% CI, 92%-100%) at 5 years, and 100% (95% CI, 86%-100%) at 10 years. Conclusions HIV-infected patients' long-term immune response up to 10 years to YFV is primarily dependent on the control of HIV replication at the time of vaccination. For those on successful cART, immune response up to 10 years is comparable to that of non-HIV-infected adults. We recommend a single YFV booster after 10 years for patients vaccinated on successful cART, whereas those vaccinated with uncontrolled HIV RNA may need an early booster.
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Affiliation(s)
- Olivia Veit
- Department of Infectious Diseases, Bern University Hospital, University of Bern.,Department of Medicine, Swiss Tropical and Public Health Institute.,University of Basel, Switzerland.,Institute of Epidemiology, Biostatistics and Prevention, University of Zürich, Switzerland
| | | | | | - Cornelia Staehelin
- Department of Infectious Diseases, Bern University Hospital, University of Bern
| | - Beat Sonderegger
- Department of Infectious Diseases, Bern University Hospital, University of Bern
| | - Delphine Héquet
- Division of Infectious Diseases, University Hospital of Lausanne
| | - Marcel Stoeckle
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, University Basel
| | - Alexandra Calmy
- Division of Infectious Diseases, University Hospital of Geneva
| | | | - Enos Bernasconi
- Division of Infectious Diseases, Regional Hospital of Lugano
| | - Domenica Flury
- Division of Infectious Diseases, Cantonal Hospital of St Gallen
| | - Christoph Hatz
- Department of Medicine, Swiss Tropical and Public Health Institute.,University of Basel, Switzerland.,Institute of Epidemiology, Biostatistics and Prevention, University of Zürich, Switzerland
| | - Marcel Zwahlen
- Institute of Social and Preventive Medicine, University of Bern, Switzerland
| | - Hansjakob Furrer
- Department of Infectious Diseases, Bern University Hospital, University of Bern
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Campi-Azevedo AC, Reis LR, Peruhype-Magalhães V, Coelho-dos-Reis JG, Antonelli LR, Fonseca CT, Costa-Pereira C, Souza-Fagundes EM, da Costa-Rocha IA, Mambrini JVDM, Lemos JAC, Ribeiro JGL, Caldas IR, Camacho LAB, Maia MDLDS, de Noronha TG, de Lima SMB, Simões M, Freire MDS, Martins RDM, Homma A, Tauil PL, Vasconcelos PFC, Romano APM, Domingues CM, Teixeira-Carvalho A, Martins-Filho OA. Short-Lived Immunity After 17DD Yellow Fever Single Dose Indicates That Booster Vaccination May Be Required to Guarantee Protective Immunity in Children. Front Immunol 2019; 10:2192. [PMID: 31616412 PMCID: PMC6775283 DOI: 10.3389/fimmu.2019.02192] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 08/30/2019] [Indexed: 12/27/2022] Open
Abstract
The Yellow Fever (YF) vaccination is recommended for people living in endemic areas and represents the most effective strategy to reduce the risk of infection. Previous studies have warned that booster regimens should be considered to guarantee the long-term persistence of 17DD-YF-specific memory components in adults living in areas with YF-virus circulation. Considering the lower seroconversion rates observed in children (9-12 months of age) as compared to adults, this study was designed in order to access the duration of immunity in single-dose vaccinated children in a 10-years cross-sectional time-span. The levels of neutralizing antibodies (PRNT) and the phenotypic/functional memory status of T and B-cells were measured at a baseline, 30-45 days, 1, 2, 4, 7, and 10 years following primary vaccination. The results revealed that a single dose induced 85% of seropositivity at 30-45 days and a progressive time-dependent decrease was observed as early as 2 years and declines toward critical values (below 60%) at time-spans of ≥4-years. Moreover, short-lived YF-specific cellular immunity, mediated by memory T and B-cells was also observed after 4-years. Predicted probability and resultant memory analysis emphasize that correlates of protection (PRNT; effector memory CD8+ T-cells; non-classical memory B-cells) wane to critical values within ≥4-years after primary vaccination. Together, these results clearly demonstrate the decline of 17DD-YF-specific memory response along time in children primarily vaccinated at 9-12 months of age and support the need of booster regimen to guarantee the long-term persistence of memory components for children living in areas with high risk of YF transmission.
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Affiliation(s)
| | - Laise Rodrigues Reis
- Instituto René Rachou, Fundação Oswaldo Cruz – FIOCRUZ-Minas, Belo Horizonte, Brazil
| | | | | | - Lis Ribeiro Antonelli
- Instituto René Rachou, Fundação Oswaldo Cruz – FIOCRUZ-Minas, Belo Horizonte, Brazil
| | | | | | | | | | | | | | | | | | | | | | | | | | - Marisol Simões
- Instituto de Tecnologia em Imunobiológicos Bio-Manguinhos – FIOCRUZ, Rio de Janeiro, Brazil
| | - Marcos da Silva Freire
- Instituto de Tecnologia em Imunobiológicos Bio-Manguinhos – FIOCRUZ, Rio de Janeiro, Brazil
| | | | - Akira Homma
- Instituto de Tecnologia em Imunobiológicos Bio-Manguinhos – FIOCRUZ, Rio de Janeiro, Brazil
| | - Pedro Luiz Tauil
- Faculdade de Medicina, Universidade de Brasília, Brasilia, Brazil
| | | | - Alessandro Pecego Martins Romano
- Departamento de Imunização e Doenças Transmissíveis (DEIDT) – Secretaria de Vigilância em Saúde, Ministério da Saúde, Brasilia, Brazil
| | - Carla Magda Domingues
- Programa Nacional de Imunizações – Secretaria de Vigilância em Saúde, Ministério da Saúde, Brasilia, Brazil
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Campi-Azevedo AC, Peruhype-Magalhāes V, Coelho-Dos-Reis JG, Antonelli LR, Costa-Pereira C, Speziali E, Reis LR, Lemos JA, Ribeiro JGL, Bastos Camacho LA, de Sousa Maia MDL, Barbosa de Lima SM, Simões M, de Menezes Martins R, Homma A, Cota Malaquias LC, Tauil PL, Costa Vasconcelos PF, Martins Romano AP, Domingues CM, Teixeira-Carvalho A, Martins-Filho OA. 17DD Yellow Fever Revaccination and Heightened Long-Term Immunity in Populations of Disease-Endemic Areas, Brazil. Emerg Infect Dis 2019; 25:1511-1521. [PMID: 31298654 PMCID: PMC6649311 DOI: 10.3201/eid2508.181432] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
We evaluated the duration of neutralizing antibodies and the status of 17DD vaccine–specific T- and B-cell memory following primary and revaccination regimens for yellow fever (YF) in Brazil. We observed progressive decline of plaque-reduction neutralization test (PRNT) seropositivity and of the levels of effector memory CD4+ and CD8+ T cells, as well as interferon-γ+CD8+ T cells, 10 years after primary vaccination. Revaccination restored PRNT seropositivity as well as the levels of effector memory CD4+, CD8+, and interferon-γ+CD8+ T cells. Moreover, secondary or multiple vaccinations guarantee long-term persistence of PRNT positivity and cell-mediated memory 10 years after booster vaccination. These findings support the relevance of booster doses to heighten the 17DD-YF–specific immune response to guarantee the long-term persistence of memory components. Secondary or multiple vaccinations improved the correlates of protection triggered by 17DD-YF primary vaccination, indicating that booster regimens are needed to achieve efficient immunity in areas with high risk for virus transmission.
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9
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Yellow fever in the diagnostics laboratory. Emerg Microbes Infect 2018; 7:129. [PMID: 30002363 PMCID: PMC6043483 DOI: 10.1038/s41426-018-0128-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 05/30/2018] [Accepted: 06/03/2018] [Indexed: 12/15/2022]
Abstract
Yellow fever (YF) remains a public health issue in endemic areas despite the availability of a safe and effective vaccine. In 2015–2016, urban outbreaks of YF were declared in Angola and the Democratic Republic of Congo, and a sylvatic outbreak has been ongoing in Brazil since December 2016. Of great concern is the risk of urban transmission cycles taking hold in Brazil and the possible spread to countries with susceptible populations and competent vectors. Vaccination remains the cornerstone of an outbreak response, but a low vaccine stockpile has forced a sparing-dose strategy, which has thus far been implemented in affected African countries and now in Brazil. Accurate laboratory confirmation of cases is critical for efficient outbreak control. A dearth of validated commercial assays for YF, however, and the shortcomings of serological methods make it challenging to implement YF diagnostics outside of reference laboratories. We examine the advantages and drawbacks of existing assays to identify the barriers to timely and efficient laboratory diagnosis. We stress the need to develop new diagnostic tools to meet current challenges in the fight against YF.
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10
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Willcox AC, Collins MH, Jadi R, Keeler C, Parr JB, Mumba D, Kashamuka M, Tshefu A, de Silva AM, Meshnick SR. Seroepidemiology of Dengue, Zika, and Yellow Fever Viruses among Children in the Democratic Republic of the Congo. Am J Trop Med Hyg 2018; 99:756-763. [PMID: 29988000 DOI: 10.4269/ajtmh.18-0156] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Flaviviruses such as Zika, dengue, and yellow fever cause epidemics throughout the tropics and account for substantial global morbidity and mortality. Although malaria and other vector-borne diseases have long been appreciated in Africa, flavivirus epidemiology is incompletely understood. Despite the existence of an effective vaccine, yellow fever continues to cause outbreaks and deaths, including at least 42 fatalities in the Democratic Republic of the Congo (DRC) in 2016. Here, we leveraged biospecimens collected as part of the nationally representative 2013-2014 Demographic and Health Survey in the DRC to examine serological evidence of flavivirus infection or vaccination in children aged 6 months to 5 years. Even in this young stratum of the Congolese population, we find evidence of infection by dengue and Zika viruses based on results from enzyme-linked immunosorbent assay and neutralization assay. Surprisingly, there was remarkable discordance between reported yellow fever vaccination status and results of serological assays. The estimated seroprevalences of neutralizing antibodies against each virus are yellow fever, 6.0% (95% confidence interval [CI] = 4.6-7.5%); dengue, 0.4% (0.1-0.9%); and Zika, 0.1% (0.0-0.5%). These results merit targeted, prospective studies to assess effectiveness of yellow fever vaccination programs, determine flavivirus seroprevalence across a broader age range, and investigate how these emerging diseases contribute to the burden of acute febrile illness in the DRC.
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Affiliation(s)
- Alexandra C Willcox
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
| | - Matthew H Collins
- Department of Medicine, Division of Infectious Diseases, Hope Clinic of the Emory Vaccine Center, Emory School of Medicine, Decatur, Georgia
| | - Ramesh Jadi
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Corinna Keeler
- Department of Geography, University of North Carolina, Chapel Hill, North Carolina
| | - Jonathan B Parr
- Department of Medicine, Division of Infectious Diseases, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Dieudonné Mumba
- Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of the Congo
| | - Melchior Kashamuka
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Antoinette Tshefu
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Aravinda M de Silva
- Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, North Carolina
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11
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Lindsey NP, Horiuchi KA, Fulton C, Panella AJ, Kosoy OI, Velez JO, Krow-Lucal ER, Fischer M, Staples JE. Persistence of yellow fever virus-specific neutralizing antibodies after vaccination among US travellers. J Travel Med 2018; 25:5139702. [PMID: 30346562 PMCID: PMC7135922 DOI: 10.1093/jtm/tay108] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 10/18/2018] [Indexed: 01/04/2023]
Abstract
BACKGROUND Few studies have assessed the duration of humoral immunity following yellow fever (YF) vaccination in a non-endemic population. We evaluated seropositivity among US resident travellers based on time post-vaccination. METHODS We identified serum samples from US travellers with YF virus-specific plaque reduction neutralization testing (PRNT) performed at CDC from 1988 to 2016. Analyses were conducted to assess the effect of time since vaccination on neutralizing antibody titer counts. RESULTS Among 234 travellers who had neutralizing antibody testing performed on a specimen obtained ≥1 month after vaccination, 13 received multiple YF vaccinations and 221 had one dose of YF vaccine reported. All 13 who received more than one dose of YF vaccine had a positive PRNT regardless of the amount time since most recent vaccination. Among the 221 travellers with one reported dose of YF vaccine, 155 (70%) were vaccinated within 10 years (range 1 month-9 years) and 66 (30%) were vaccinated ≥10 years (range 10-53 years) prior to serum collection. Among the 155 individuals vaccinated, <10 years prior to serum collection, 146 (94%) had a positive PRNT compared with 82% (54/66) of individuals vaccinated ≥10 years prior to serum collection (P = 0.01). Post-vaccination PRNT titers showed a time-dependent decrease. Individuals with immunocompromising conditions were less likely to have a positive PRNT (77%) compared with those who were not immunocompromised (92%; P = 0.04). CONCLUSION Although the percentage of vaccinees with a positive PRNT and antibody titers decreased over time, a single dose of YF vaccine provided long-lasting protection in the majority of US travellers. A booster dose could be considered for certain travellers who are planning travel to a high risk area based on immune competence and time since vaccination.
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Affiliation(s)
- Nicole P Lindsey
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Kalanthe A Horiuchi
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Corey Fulton
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Amanda J Panella
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Olga I Kosoy
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Jason O Velez
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Elizabeth R Krow-Lucal
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Marc Fischer
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - J Erin Staples
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
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12
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Adaptive immune responses to booster vaccination against yellow fever virus are much reduced compared to those after primary vaccination. Sci Rep 2017; 7:662. [PMID: 28386132 PMCID: PMC5429613 DOI: 10.1038/s41598-017-00798-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 03/13/2017] [Indexed: 12/05/2022] Open
Abstract
Outbreaks of Yellow Fever occur regularly in endemic areas of Africa and South America frequently leading to mass vaccination campaigns straining the availability of the attenuated Yellow Fever vaccine, YF-17D. The WHO has recently decided to discontinue regular booster-vaccinations since a single vaccination is deemed to confer life-long immune protection. Here, we have examined humoral (neutralizing antibody) and cellular (CD8 and CD4 T cell) immune responses in primary and booster vaccinees (the latter spanning 8 to 36 years after primary vaccination). After primary vaccination, we observed strong cellular immune responses with T cell activation peaking ≈2 weeks and subsiding to background levels ≈ 4 weeks post-vaccination. The number of antigen-specific CD8+ T cells declined over the following years. In >90% of vaccinees, in vitro expandable T cells could still be detected >10 years post-vaccination. Although most vaccinees responded to a booster vaccination, both the humoral and cellular immune responses observed following booster vaccination were strikingly reduced compared to primary responses. This suggests that pre-existing immunity efficiently controls booster inoculums of YF-17D. In a situation with epidemic outbreaks, one could argue that a more efficient use of a limited supply of the vaccine would be to focus on primary vaccinations.
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13
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Grobusch MP, van Aalst M, Goorhuis A. Yellow fever vaccination - Once in a lifetime? Travel Med Infect Dis 2016; 15:1-2. [PMID: 28013052 DOI: 10.1016/j.tmaid.2016.12.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 12/16/2016] [Accepted: 12/19/2016] [Indexed: 10/20/2022]
Affiliation(s)
- Martin P Grobusch
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center, University of Amsterdam, The Netherlands.
| | - Mariëlle van Aalst
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Abraham Goorhuis
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center, University of Amsterdam, The Netherlands
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Amanna IJ, Slifka MK. Questions regarding the safety and duration of immunity following live yellow fever vaccination. Expert Rev Vaccines 2016; 15:1519-1533. [PMID: 27267203 PMCID: PMC5171234 DOI: 10.1080/14760584.2016.1198259] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 06/02/2016] [Indexed: 10/21/2022]
Abstract
INTRODUCTION The World Health Organization (WHO) and other health agencies have concluded that yellow fever booster vaccination is unnecessary since a single dose of vaccine confers lifelong immunity. Areas covered: We reviewed the clinical studies cited by health authorities in their investigation of both the safety profile and duration of immunity for the YFV-17D vaccine and examined the position that booster vaccination is no longer needed. We found that antiviral immunity may be lost in 1-in-3 to 1-in-5 individuals within 5 to 10 years after a single vaccination and that children may be at greater risk for primary vaccine failure. The safety profile of YFV-17D was compared to other licensed vaccines including oral polio vaccine (OPV) and the rotavirus vaccine, RotaShield, which have subsequently been withdrawn from the US and world market, respectively. Expert commentary: Based on these results and recent epidemiological data on vaccine failures (particularly evident at >10 years after vaccination), we believe that current recommendations to no longer administer YFV-17D booster vaccination be carefully re-evaluated, and that further development of safer vaccine approaches should be considered.
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Affiliation(s)
- Ian J. Amanna
- Najít Technologies, Inc., 505 NW 185 Avenue, Beaverton, OR 97006, USA
| | - Mark K. Slifka
- Division of Neuroscience, Oregon National Primate Research Center, Department of Molecular Microbiology and Immunology, Oregon Health & Science University, 505 NW 185 Avenue, Beaverton, OR 97006, USA
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15
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Wieten RW, Jonker EFF, van Leeuwen EMM, Remmerswaal EBM, ten Berge IJM, de Visser AW, van Genderen PJJ, Goorhuis A, Visser LG, Grobusch MP, de Bree GJ. A Single 17D Yellow Fever Vaccination Provides Lifelong Immunity; Characterization of Yellow-Fever-Specific Neutralizing Antibody and T-Cell Responses after Vaccination. PLoS One 2016; 11:e0149871. [PMID: 26977808 PMCID: PMC4792480 DOI: 10.1371/journal.pone.0149871] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 02/07/2016] [Indexed: 01/16/2023] Open
Abstract
INTRODUCTION Prompted by recent amendments of Yellow Fever (YF) vaccination guidelines from boost to single vaccination strategy and the paucity of clinical data to support this adjustment, we used the profile of the YF-specific CD8+ T-cell subset profiles after primary vaccination and neutralizing antibodies as a proxy for potentially longer lasting immunity. METHODS AND FINDINGS PBMCs and serum were collected in six individuals on days 0, 3, 5, 12, 28 and 180, and in 99 individuals >10 years after YF-vaccination. Phenotypic characteristics of YF- tetramer+ CD8+ T-cells were determined using class I tetramers. Antibody responses were measured using a standardized plaque reduction neutralization test (PRNT). Also, characteristics of YF-tetramer positive CD8+ T-cells were compared between individuals who had received a primary- and a booster vaccination. YF-tetramer+ CD8+ T-cells were detectable on day 12 (median tetramer+ cells as percentage of CD8+ T-cells 0.2%, range 0.07-3.1%). On day 180, these cells were still present (median 0.06%, range 0.02-0.78%). The phenotype of YF-tetramer positive CD8+ T-cells shifted from acute phase effector cells on day 12, to late differentiated or effector memory phenotype (CD45RA-/+CD27-) on day 28. Two subsets of YF-tetramer positive T-cells (CD45RA+CD27- and CD45RA+CD27+) persisted until day 180. Within all phenotypic subsets, the T-bet: Eomes ratio tended to be high on day 28 after vaccination and shifted towards predominant Eomes expression on day 180 (median 6.0 (day 28) vs. 2.2 (day 180) p = 0.0625), suggestive of imprinting compatible with long-lived memory properties. YF-tetramer positive CD8+ T-cells were detectable up to 18 years post vaccination, YF-specific antibodies were detectable up to 40 years after single vaccination. Booster vaccination did not increase titers of YF-specific antibodies (mean 12.5 vs. 13.1, p = 0.583), nor induce frequencies or alter phenotypes of YF-tetramer+ CD8+ T-cells. CONCLUSION The presence of a functionally competent YF-specific memory T-cell pool 18 years and sufficient titers of neutralizing antibodies 35-40 years after first vaccination suggest that single vaccination may be sufficient to provide long-term immunity.
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Affiliation(s)
- Rosanne W. Wieten
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Emile F. F. Jonker
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, the Netherlands
| | - Ester M. M. van Leeuwen
- Department of Experimental Immunology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Ester B. M. Remmerswaal
- Department of Experimental Immunology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Renal Transplant Unit, Division of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Ineke J. M. ten Berge
- Department of Experimental Immunology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Renal Transplant Unit, Division of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Adriëtte W. de Visser
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, the Netherlands
| | | | - Abraham Goorhuis
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Leo G. Visser
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, the Netherlands
| | - Martin P. Grobusch
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Godelieve J. de Bree
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Amsterdam Institute for Global Health and Development, Amsterdam, the Netherlands
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Occurrence of Autoimmune Diseases Related to the Vaccine against Yellow Fever. Autoimmune Dis 2014; 2014:473170. [PMID: 25405025 PMCID: PMC4227414 DOI: 10.1155/2014/473170] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 09/08/2014] [Accepted: 09/22/2014] [Indexed: 11/18/2022] Open
Abstract
Yellow fever is an infectious disease, endemic in South America and Africa. This is a potentially serious illness, with lethality between 5 and 40% of cases. The most effective preventive vaccine is constituted by the attenuated virus strain 17D, developed in 1937. It is considered safe and effective, conferring protection in more than 90% in 10 years. Adverse effects are known as mild reactions (allergies, transaminases transient elevation, fever, headache) and severe (visceral and neurotropic disease related to vaccine). However, little is known about its potential to induce autoimmune responses. This systematic review aims to identify the occurrence of autoinflammatory diseases related to 17D vaccine administration. Six studies were identified describing 13 possible cases. The diseases were Guillain-Barré syndrome, multiple sclerosis, multiple points evanescent syndrome, acute disseminated encephalomyelitis, autoimmune hepatitis, and Kawasaki disease. The data suggest that 17D vaccination may play a role in the mechanism of loss of self-tolerance.
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17
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Duration of post-vaccination immunity against yellow fever in adults. Vaccine 2014; 32:4977-84. [PMID: 25090646 DOI: 10.1016/j.vaccine.2014.07.021] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 05/24/2014] [Accepted: 07/08/2014] [Indexed: 11/18/2022]
Abstract
INTRODUCTION Available scientific evidence to recommend or to advise against booster doses of yellow fever vaccine (YFV) is inconclusive. A study to estimate the seropositivity rate and geometric mean titres (GMT) of adults with varied times of vaccination was aimed to provide elements to revise the need and the timing of revaccination. METHODS Adults from the cities of Rio de Janeiro and Alfenas located in non-endemic areas in the Southeast of Brazil, who had one dose of YFV, were tested for YF neutralising antibodies and dengue IgG. Time (in years) since vaccination was based on immunisation cards and other reliable records. RESULTS From 2011 to 2012 we recruited 691 subjects (73% males), aged 18-83 years. Time since vaccination ranged from 30 days to 18 years. Seropositivity rates (95%C.I.) and GMT (International Units/mL; 95%C.I.) decreased with time since vaccination: 93% (88-96%), 8.8 (7.0-10.9) IU/mL for newly vaccinated; 94% (88-97), 3.0 (2.5-3.6) IU/mL after 1-4 years; 83% (74-90), 2.2 (1.7-2.8) IU/mL after 5-9 years; 76% (68-83), 1.7 (1.4-2.0) IU/mL after 10-11 years; and 85% (80-90), 2.1 (1.7-2.5) IU/mL after 12 years or more. YF seropositivity rates were not affected by previous dengue infection. CONCLUSIONS Eventhough serological correlates of protection for yellow fever are unknown, seronegativity in vaccinated subjects may indicate primary immunisation failure, or waning of immunity to levels below the protection threshold. Immunogenicity of YFV under routine conditions of immunisation services is likely to be lower than in controlled studies. Moreover, infants and toddlers, who comprise the main target group in YF endemic regions, and populations with high HIV infection rates, respond to YFV with lower antibody levels. In those settings one booster dose, preferably sooner than currently recommended, seems to be necessary to ensure longer protection for all vaccinees.
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18
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Wieten RW, van der Schalie M, Visser BJ, Grobusch MP, van Vugt M. Risk factors and pre-travel healthcare of international travellers attending a Dutch travel clinic: a cross-sectional analysis. Travel Med Infect Dis 2014; 12:511-24. [PMID: 25087666 DOI: 10.1016/j.tmaid.2014.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 05/13/2014] [Accepted: 05/14/2014] [Indexed: 12/01/2022]
Abstract
BACKGROUND The number of international travellers is currently estimated to exceed one billion annually. To address travel related health risks and facilitate risk reduction strategies, detailed knowledge of travellers' characteristics is important. METHOD In this cross-sectional study, data of a 20% sample of travellers visiting the Academic Medical Center (AMC) travel clinic Amsterdam from July 2011 to July 2012 was collected. Itineraries and protection versus exposure rates of preventable infectious diseases were mapped and reported according to STROBE guidelines. RESULTS 1749 travellers were included. South-Eastern Asia, South-America and West-Africa were most frequently visited. 26.2% of the population had pre-existing medical conditions (often cardiovascular). Young and VFR travellers had a longer median travel time (28 and 30 days) compared to the overall population (21 days). Young adult travellers were relatively often vaccinated against hepatitis B (43.9% vs. 20.5%, p < .001) and rabies (16.6% vs. 4.3%, p < .001). VFRs were less often vaccinated against hepatitis B (11.6% vs. 30.6%, p < .001) and rabies (1.3% vs. 9.0%, p .012) compared to non-VFR travellers. CONCLUSIONS Pre-travel guidelines were well adhered to. Young adult travellers had high-risk itineraries but were adequately protected. Improvement of hepatitis B and rabies protection would be desirable, specifically for VFRs.
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Affiliation(s)
- Rosanne W Wieten
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands(1)
| | - Maurice van der Schalie
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands(1)
| | - Benjamin J Visser
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands(1)
| | - Martin P Grobusch
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands(1).
| | - Michèle van Vugt
- Center of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands(1)
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Slifka MK, Amanna I. How advances in immunology provide insight into improving vaccine efficacy. Vaccine 2014; 32:2948-57. [PMID: 24709587 PMCID: PMC4096845 DOI: 10.1016/j.vaccine.2014.03.078] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Revised: 03/13/2014] [Accepted: 03/25/2014] [Indexed: 01/08/2023]
Abstract
Vaccines represent one of the most compelling examples of how biomedical research has improved society by saving lives and dramatically reducing the burden of infectious disease. Despite the importance of vaccinology, we are still in the early stages of understanding how the best vaccines work and how we can achieve better protective efficacy through improved vaccine design. Most successful vaccines have been developed empirically, but recent advances in immunology are beginning to shed new light on the mechanisms of vaccine-mediated protection and development of long-term immunity. Although natural infection will often elicit lifelong immunity, almost all current vaccines require booster vaccination in order to achieve durable protective humoral immune responses, regardless of whether the vaccine is based on infection with replicating live-attenuated vaccine strains of the specific pathogen or whether they are derived from immunization with inactivated, non-replicating vaccines or subunit vaccines. The form of the vaccine antigen (e.g., soluble or particulate/aggregate) appears to play an important role in determining immunogenicity and the interactions between dendritic cells, B cells and T cells in the germinal center are likely to dictate the magnitude and duration of protective immunity. By learning how to optimize these interactions, we may be able to elicit more effective and long-lived immunity with fewer vaccinations.
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Affiliation(s)
- Mark K Slifka
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Sciences University, 505 NW 185th Avenue, Beaverton, OR 97006, USA.
| | - Ian Amanna
- Najít Technologies, Inc., 505 NW 185th Avenue, Beaverton, OR 97006, USA
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