1
|
A comparative analysis on the physicochemical properties of tick-borne encephalitis virus envelope protein residues that affect its antigenic properties. Virus Res 2017. [PMID: 28625666 DOI: 10.1016/j.virusres.2017.06.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
This work is dedicated to the study of the variability of the main antigenic envelope protein E among different strains of tick-borne encephalitis virus at the level of physical and chemical properties of the amino acid residues. E protein variants were extracted from then NCBI database. Four amino acid residues properties in the polypeptide sequences were investigated: the average volume of the amino acid residue in the protein tertiary structure, the number of amino acid residue hydrogen bond donors, the charge of amino acid residue lateral radical and the dipole moment of the amino acid residue. These physico-chemical properties are involved in antigen-antibody interactions. As a result, 103 different variants of the antigenic determinants of the tick-borne encephalitis virus E protein were found, significantly different by physical and chemical properties of the amino acid residues in their structure. This means that some strains among the natural variants of tick-borne encephalitis virus can potentially escape the immune response induced by the standard vaccine.
Collapse
|
2
|
Lani R, Moghaddam E, Haghani A, Chang LY, AbuBakar S, Zandi K. Tick-borne viruses: a review from the perspective of therapeutic approaches. Ticks Tick Borne Dis 2014; 5:457-65. [PMID: 24907187 DOI: 10.1016/j.ttbdis.2014.04.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 03/07/2014] [Accepted: 04/01/2014] [Indexed: 12/30/2022]
Abstract
Several important human diseases worldwide are caused by tick-borne viruses. These diseases have become important public health concerns in recent years. The tick-borne viruses that cause diseases in humans mainly belong to 3 families: Bunyaviridae, Flaviviridae, and Reoviridae. In this review, we focus on therapeutic approaches for several of the more important tick-borne viruses from these 3 families. These viruses are Crimean-Congo hemorrhagic fever virus (CCHF) and the newly discovered tick-borne phleboviruses, known as thrombocytopenia syndromevirus (SFTSV), Heartland virus and Bhanja virus from the family Bunyaviridae, tick-borne encephalitis virus (TBEV), Powassan virus (POWV), Louping-ill virus (LIV), Omsk hemorrhagic fever virus (OHFV), Kyasanur Forest disease virus (KFDV), and Alkhurma hemorrhagic fever virus (AHFV) from the Flaviviridae family. To date, there is no effective antiviral drug available against most of these tick-borne viruses. Although there is common usage of antiviral drugs such as ribavirin for CCHF treatment in some countries, there are concerns that ribavirin may not be as effective as once thought against CCHF. Herein, we discuss also the availability of vaccines for the control of these viral infections. The lack of treatment and prevention approaches for these viruses is highlighted, and we hope that this review may increase public health awareness with regard to the threat posed by this group of viruses.
Collapse
Affiliation(s)
- Rafidah Lani
- Tropical Infectious Disease Research and Education Centre (TIDREC), Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Ehsan Moghaddam
- Tropical Infectious Disease Research and Education Centre (TIDREC), Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Amin Haghani
- Department of Environmental and Occupational Health, Faculty of Medicine and Health Sciences, University Putra Malaysia, Malaysia
| | - Li-Yen Chang
- Tropical Infectious Disease Research and Education Centre (TIDREC), Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Sazaly AbuBakar
- Tropical Infectious Disease Research and Education Centre (TIDREC), Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Keivan Zandi
- Tropical Infectious Disease Research and Education Centre (TIDREC), Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| |
Collapse
|
3
|
Go YY, Balasuriya UBR, Lee CK. Zoonotic encephalitides caused by arboviruses: transmission and epidemiology of alphaviruses and flaviviruses. Clin Exp Vaccine Res 2013; 3:58-77. [PMID: 24427764 PMCID: PMC3890452 DOI: 10.7774/cevr.2014.3.1.58] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 10/03/2013] [Accepted: 10/20/2013] [Indexed: 12/29/2022] Open
Abstract
In this review, we mainly focus on zoonotic encephalitides caused by arthropod-borne viruses (arboviruses) of the families Flaviviridae (genus Flavivirus) and Togaviridae (genus Alphavirus) that are important in both humans and domestic animals. Specifically, we will focus on alphaviruses (Eastern equine encephalitis virus, Western equine encephalitis virus, Venezuelan equine encephalitis virus) and flaviviruses (Japanese encephalitis virus and West Nile virus). Most of these viruses were originally found in tropical regions such as Africa and South America or in some regions in Asia. However, they have dispersed widely and currently cause diseases around the world. Global warming, increasing urbanization and population size in tropical regions, faster transportation and rapid spread of arthropod vectors contribute in continuous spreading of arboviruses into new geographic areas causing reemerging or resurging diseases. Most of the reemerging arboviruses also have emerged as zoonotic disease agents and created major public health issues and disease epidemics.
Collapse
Affiliation(s)
- Yun Young Go
- Virus Research and Testing Group, Division of Drug Discovery Research, Korea Research Institute of Chemical Technology, Daejeon, Korea
| | - Udeni B R Balasuriya
- Maxwell H. Gluck Equine Research Center, Department of Veterinary Science, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, USA. ; Department of Microbiology, Immunology and Molecular Genetics, College of Medicine, University of Kentucky, Lexington, KY, USA
| | - Chong-Kyo Lee
- Virus Research and Testing Group, Division of Drug Discovery Research, Korea Research Institute of Chemical Technology, Daejeon, Korea
| |
Collapse
|
4
|
Metz SW, Pijlman GP. Arbovirus vaccines; opportunities for the baculovirus-insect cell expression system. J Invertebr Pathol 2011; 107 Suppl:S16-30. [PMID: 21784227 DOI: 10.1016/j.jip.2011.05.002] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2011] [Revised: 02/08/2011] [Accepted: 02/08/2011] [Indexed: 02/06/2023]
Abstract
The baculovirus-insect cell expression system is a well-established technology for the production of heterologous viral (glyco)proteins in cultured cells, applicable for basic scientific research as well as for the development and production of vaccines and diagnostics. Arboviruses form an emerging group of medically important viral pathogens that are transmitted to humans and animals via arthropod vectors, mostly mosquitoes, ticks or midges. Few arboviral vaccines are currently available, but there is a growing need for safe and effective vaccines against some highly pathogenic arboviruses such as Chikungunya, dengue, West Nile, Rift Valley fever and Bluetongue viruses. This comprehensive review discusses the biology and current state of the art in vaccine development for arboviruses belonging to the families Togaviridae, Flaviviridae, Bunyaviridae and Reoviridae and the potential of the baculovirus-insect cell expression system for vaccine antigen production The members of three of these four arbovirus families have enveloped virions and display immunodominant glycoproteins with a complex structure at their surface. Baculovirus expression of viral antigens often leads to correctly folded and processed (glyco)proteins able to induce protective immunity in animal models and humans. As arboviruses occupy a unique position in the virosphere in that they also actively replicate in arthropod cells, the baculovirus-insect cell expression system is well suited to produce arboviral proteins with correct folding and post-translational processing. The opportunities for recombinant baculoviruses to aid in the development of safe and effective subunit and virus-like particle vaccines against arboviral diseases are discussed.
Collapse
Affiliation(s)
- Stefan W Metz
- Laboratory of Virology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | | |
Collapse
|
5
|
Abstract
BACKGROUND Tick-borne encephalitis (TBE) is a disease of the central nervous system caused by a tick-borne viral infection. TBE can lead to severe neurological syndromes such as meningitis, meningoencephalitis, and meningoencephalomyelitis, which can result in death. There is no treatment, and prevention with the vaccine is the only intervention currently available. OBJECTIVES To evaluate vaccines for preventing TBE in terms of effectiveness and adverse effects. SEARCH STRATEGY In June 2008, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (The Cochrane Library 2008, Issue 2), MEDLINE, EMBASE, LILACS, and mRCT. We also checked reference lists of articles. SELECTION CRITERIA Randomized and quasi-randomized controlled trials comparing TBE vaccines against placebo, control vaccines, no intervention, or a different dose or schedule of the intervention vaccine. DATA COLLECTION AND ANALYSIS Two authors applied the inclusion criteria, extracted data, and assessed each trial's risk of bias. We could not combine the included trials in a meta-analysis because of differences in comparisons and outcomes. MAIN RESULTS Eleven trials (corresponding to 10 papers) involving 8184 participants (6586 adults and 1598 children) were included. Different versions of three types of TBE vaccines were tested (IPVE, FSME-IMMUN, and Encepur); out of which only three (Encepur children, Encepur Adults, and FSME-IMMUN "new") are currently licensed. No trials reported on cases of clinical TBE, but all reported on antibody titre (seroconversion). All the vaccines gave seroconversion rates of over 87%. Systemic and local adverse effects were common; none were severe or life threatening. AUTHORS' CONCLUSIONS Tick-borne encephalitis vaccines appear to be highly immunogenic, but the relationship between seroconversion and clinical protection has not been established. Although adverse effects were commonly reported, none were serious or life threatening.
Collapse
Affiliation(s)
- Vittorio Demicheli
- Health Councillorship - Servizio Regionale di Riferimento per l'Epidemiologia, SSEpi-SeREMI - Azienda Sanitaria Locale ASL AL, C.so Regina Margherita 153 bis, Torino, Piemonte, Italy, 10122.
| | | | | |
Collapse
|
6
|
Schöndorf I, Beran J, Cizkova D, Lesna V, Banzhoff A, Zent O. Tick-borne encephalitis (TBE) vaccination: Applying the most suitable vaccination schedule. Vaccine 2007; 25:1470-5. [PMID: 17196713 DOI: 10.1016/j.vaccine.2006.10.028] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Accepted: 10/18/2006] [Indexed: 11/22/2022]
Abstract
Tick-borne encephalitis (TBE) is caused by an arthropod-borne virus, belonging to the family of Flaviviridae. In case of disease, which can lead to neurological sequelae or even fatal outcomes, only symptomatic treatment is available. TBE can be prevented by vaccination. Various primary immunization schedules have been developed. To identify the most suitable schedule, the present randomised, controlled study was designed to provide data on the immune response elicited by four different immunization schedules obtained by ELISA and by neutralization test (NT). A total of 398 healthy subjects aged > or =12 years were randomised to vaccination according to either the rapid schedule (Group R, vaccination on days 0, 7 and 21), the conventional schedule (Group C, vaccination on days 0, 28 and 300), the modified conventional schedule (Group M, vaccination on days 0, 21 and 300) or the accelerated conventional schedule (Group A, vaccination on days 0, 14 and 300). Within 3 weeks (i.e. by day 21) antibody levels were higher in Group R and Group A than in Group M and Group C. Group R and Group C both had higher titres on days 42, 180 and 300, than Group A and Group M. The rapid schedule thus combines the advantages of fast protection and of high titres over the observation period of 300 days.
Collapse
Affiliation(s)
- I Schöndorf
- Novartis Vaccines and Diagnostics GmbH and Co. KG, Clinical Research and Medical Affairs, Emil-von-Behring-Str. 76, 35041 Marburg, Germany.
| | | | | | | | | | | |
Collapse
|
7
|
Leonova GN, Ternovoi VA, Pavlenko EV, Maistrovskaya OS, Protopopova EV, Loktev VB. Evaluation of vaccine Encepur® Adult for induction of human neutralizing antibodies against recent Far Eastern subtype strains of tick-borne encephalitis virus. Vaccine 2007; 25:895-901. [PMID: 17011677 DOI: 10.1016/j.vaccine.2006.09.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2006] [Revised: 08/14/2006] [Accepted: 09/04/2006] [Indexed: 11/26/2022]
Abstract
We studied humoral immune response of 44 volunteers from Primorsky krai (Russia) immunized with the vaccine Encepur Adult. Induction of the humoral response towards the recently isolated tick-borne encephalitis virus (TBEV) strains P-69, P-202, and P-73 was evaluated by neutralization test and enzyme immunoassay. These strains belong to Far Eastern TBEV subtype based on their genotype and antigenic structure but maintain significant genetic and antigenic variability. The average geometric titers of neutralizing antibodies to P-69, P-202, and P-73 strains were 1:28, 1:34, and 1:128, respectively. The percentage of volunteers with neutralizing antibodies to these strains after complete course immunization was 63.9, 97.6, and 95.5%, respectively. We concluded that Encepur Adult vaccine induced pronounced humoral immune response towards genetically and antigenically heterogeneous strains of the Far Eastern TBEV subtype.
Collapse
Affiliation(s)
- Galina N Leonova
- Institute of Epidemiology and Microbiology, Siberian Branch of the Russian Academy of Medical Sciences, Vladivostok, Russia
| | | | | | | | | | | |
Collapse
|
8
|
Loew-Baselli A, Konior R, Pavlova BG, Fritsch S, Poellabauer E, Maritsch F, Harmacek P, Krammer M, Barrett PN, Ehrlich HJ. Safety and immunogenicity of the modified adult tick-borne encephalitis vaccine FSME-IMMUN®: Results of two large phase 3 clinical studies. Vaccine 2006; 24:5256-63. [PMID: 16624457 DOI: 10.1016/j.vaccine.2006.03.061] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2005] [Revised: 02/23/2006] [Accepted: 03/20/2006] [Indexed: 10/24/2022]
Abstract
A prospective, randomised, multicentre, single-blind phase 3 study was performed to assess the safety of a vaccination schedule consisting of two vaccinations (21-35 days apart) with the tick-borne encephalitis (TBE) vaccine FSME-IMMUN "adults" (five consecutive lots) in comparison to another licensed TBE vaccine (Encepur), with polygeline) (two lots) in healthy volunteers (n=3966) aged 16-65 years. The safety of the third vaccination with FSME-IMMUN "adults" (6 months after the first vaccination) was investigated in a follow-up study on the same population (n=3705) and TBE antibody titres were analysed pre- and post-vaccination in a subgroup of volunteers (n=564). Following the first vaccination, the overall incidence of fever (> or =38.0 degrees C) was 0.8% in the FSME-IMMUN "adults" study group and 5.6% in the comparator study group; fever was mainly mild. The fever rate after the second vaccination was 0.6% and 0.5% in the two study groups, respectively. Local and systemic reactions after the first vaccination occurred with a lower frequency in the FSME-IMMUN "adults" study group than in the comparator group. Upon analysing the tolerability of the third vaccination with FSME-IMMUN "adults", similar results were determined in both study groups of volunteers previously vaccinated with FSME-IMMUN "adults" or with the comparator vaccine. The immunogenicity results demonstrated similar seroconversion rates (as determined by ELISA or neutralization test) before and after the third vaccination in the FSME-IMMUN "adults" group and in the comparator group respectively. The results of both studies demonstrate that: (1) FSME-IMMUN "adults" is safe and highly immunogenic, (2) all five production lots of FSME-IMMUN "adults" were consistent with respect to a low rate of adverse events, (3) FSME-IMMUN "adults" induces considerably lower adverse reaction rates than the comparator vaccine after the first vaccination, and (4) two vaccinations with the comparator vaccine can be successfully followed by a third vaccination with FSME-IMMUN "adults".
Collapse
Affiliation(s)
- A Loew-Baselli
- Baxter BioScience, Global Clinical R&D, Industriestr. 67, A-1221Vienna, Austria
| | | | | | | | | | | | | | | | | | | |
Collapse
|
9
|
Abstract
Tick-borne encephalopathies constitute a broad range of infectious diseases affecting the brain and other parts of the CNS. The causative agents are both viral and bacterial. This review focuses on the current most important tick-borne human diseases: tick-borne encephalitis (TBE; including Powassan encephalitis) and Lyme borreliosis. Rocky Mountain spotted fever (RMSF) and Colorado tick fever (CTF), less common tick-borne diseases associated with encephalopathy, are also discussed. TBE is the most important flaviviral infection of the CNS in Europe and Russia, with 10 000-12 000 people diagnosed annually. The lethality of TBE in Europe is 0.5% and a post-encephalitic syndrome is seen in over 40% of affected patients, often producing a pronounced impairment in quality of life. There is no specific treatment for TBE. Two vaccines are available to prevent infection. Although these have a good protection rate and good efficacy, there are few data on long-term immunity. Lyme borreliosis is the most prevalent tick-borne disease in Europe and North America, with >50 000 cases annually. Localised early disease can be treated with oral phenoxymethylpenicillin (penicillin V), doxycycline or amoxicillin. The later manifestations of meningitis, arthritis or acrodermatitis can be treated with oral doxycycline, oral amoxicillin or intravenous ceftriaxone; intravenous benzylpenicillin (penicillin G) or cefotaxime can be used as alternatives. The current use of vaccines against Lyme borreliosis in North America is under discussion, as the LYMErix vaccine has been withdrawn from the market because of possible adverse effects, for example, arthritis. RMSF and CTF appear only in North America. RMSF is an important rickettsial disease and is effectively treated with doxycycline. There is no treatment or preventative measure available for CTF.
Collapse
Affiliation(s)
- Göran Günther
- Infectious Diseases, Department of Medical Sciences, Akademiska Sjukhuset, Uppsala University Hospital, Uppsala, Sweden.
| | | |
Collapse
|
10
|
Rumyantsev AA, Chanock RM, Murphy BR, Pletnev AG. Comparison of live and inactivated tick-borne encephalitis virus vaccines for safety, immunogenicity and efficacy in rhesus monkeys. Vaccine 2005; 24:133-43. [PMID: 16115704 DOI: 10.1016/j.vaccine.2005.07.067] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2005] [Accepted: 07/28/2005] [Indexed: 10/25/2022]
Abstract
Three antigenic chimeric live attenuated tick-borne encephalitis virus (TBEV) vaccine candidates were compared for level of replication in murine and human neuroblastoma cells, for neurovirulence and neuroinvasiveness in mice, and for safety, immunogenicity and efficacy in rhesus monkeys. Two chimeric viruses were generated by replacing the membrane precursor and envelope protein genes of dengue type 4 virus (DEN4) with the corresponding genes of a Far Eastern TBEV, Sofjin strain, in the presence (TBEV/DEN4Delta30) or absence (TBEV/DEN4) of a 30 nucleotide deletion (Delta30) in the 3' noncoding region of the DEN4 part of the chimeric genome. A third chimeric TBEV vaccine candidate was based on the antigenically distant, but naturally attenuated Langat virus (LGT). Chimerization of LGT with DEN4 resulted in decreased neurovirulence and neuroinvasiveness in mice and highly restricted viremia in rhesus monkeys. Also, the LGT/DEN4 chimera was highly restricted in replication in both murine and human neuroblastoma cells. In contrast, TBEV/DEN4 and TBEV/DEN4Delta30 were neither attenuated for neurovirulence in the mice nor restricted in replication in the neuroblastoma cells. However, both were highly attenuated for neuroinvasiveness in mice. TBEV/DEN4 replicated to moderately high titer in rhesus monkeys (mean peak viremia=10(3.1)PFU/ml) indicating that the TBEV/DEN4 chimerization had only a modest, if any, attenuating effect in monkeys. However, the addition of the Delta30 mutation to TBEV/DEN4 greatly attenuated the chimeric virus for rhesus monkeys (mean peak viremia=10(0.7)PFU/ml) and induced a higher level of antibody against the TBEV than did LGT/DEN4. A single dose of either highly attenuated TBEV/DEN4Delta30 or LGT/DEN4 vaccine candidate or three doses of an inactivated TBEV vaccine were efficacious in monkeys against wild-type LGT challenge. These results indicate that both TBEV/DEN4Delta30 and LGT/DEN4 are safe and efficacious in rhesus monkeys and should be further evaluated as vaccine candidates for use in humans.
Collapse
Affiliation(s)
- Alexander A Rumyantsev
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, MSC 8133, Bethesda, MD 20892-8133, USA
| | | | | | | |
Collapse
|
11
|
Zent O, Hennig R, Banzhoff A, Bröker M. Protection against tick-borne encephalitis with a new vaccine formulation free of protein-derived stabilizers. J Travel Med 2005; 12:85-93. [PMID: 15996453 DOI: 10.2310/7060.2005.12205] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Vaccination against tick-borne encephalitis (TBE) has been successfully employed for many years in TBE-endemic countries. Post-marketing experience gained from widespread use, however, prompted the development of improved TBE vaccines, the most modern versions of which do not contain the commonly used protein-derived stabilizers (human albumin or polygeline) of former vaccines. METHOD This article summarizes both the medical need for and clinical experience with a new TBE vaccine formulation (pediatric and adult versions). To this end, data from clinical trials and post-marketing experience are presented. The clinical database comprises immunogenicity and/or safety data of approximately 7,500 subjects ages 1 to 77 years who participated in eight clinical trials. The clinical trials were conducted at 69 centers in five European countries. Post-marketing experience includes safety data from passive pharmacovigilance systems in 18 countries where these vaccines have been licensed since 2001. RESULTS All subjects analyzed for immunogenicity achieved postimmunization levels of TBE antibodies that meet the definition of seroconversion or represent a fourfold increase. The pooled data of clinical trials revealed the expected rate of solicited local and systemic reactions. The majority of these transient postimmunization reactions were mild. Pharmacovigilance data confirm the high level of safety of these new TBE vaccines: only a common range of the side effects already noted for licensed TBE vaccines was reported. After the distribution of more than five million vaccine doses, no potential safety risk was noted. CONCLUSION Post-marketing experience supports results from clinical trials showing that these new TBE vaccines may safely be used for the vaccination of children, adolescents, and adults.
Collapse
Affiliation(s)
- Olaf Zent
- Clinical Research and Medical Affairs, Chiron Vaccines, Marburg, Germany
| | | | | | | |
Collapse
|
12
|
Desjeux G, Galoisy-Guibal L, Colin C. Cost-benefit analysis of vaccination against tick-borne encephalitis among French troops. PHARMACOECONOMICS 2005; 23:913-26. [PMID: 16153134 DOI: 10.2165/00019053-200523090-00004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
BACKGROUND French troops are exposed to tick-borne encephalitis (TBE) during their tours of duty in the Balkans. This disease, potentially serious because of its lethality and morbidity, has an effective vaccination. The epidemiological characteristics of TBE in the Balkans are not well known. OBJECTIVE In order to provide the French Department of Defence with arguments on the utility of vaccinating troops on missions in this area of Europe, we conducted a cost-benefit study. DESIGN AND SETTING Through a decision analysis, we estimated the net benefit of a three-injection vaccination programme for all French military personnel in the Balkans versus no vaccination during a period from 2004 to 2014. We used a review of the literature to estimate the parameters necessary for the present study: the disease's morbidity and death incidence rate; the disease's sequelae; and the adverse effects of the vaccination. The initial hypothesis of the seroconversion rate of TBE in the Balkans was 834 per 100,000 person-years. Human life was valued in Euro (year 2004 values) by calculating the amounts paid by the French Department of Defence to military personnel in case of disabling sequelae and to their heirs in case of death. MAIN RESULTS The net benefit was negative: -5.68 million Euro. The vaccination programme's cost was 10.05 million Euro. 121 cases of TBE could be prevented by this vaccination; however, the sensitivity analysis showed that the results are closely related to the incidence of the disease. CONCLUSION Very high incidence rates of TBE were initially hypothesised compared with what has actually been reported. As a result, the vaccination programme against TBE for French military personnel should not be implemented unless the objective of the armed forces is to prevent all cases of TBE and they are willing to assume the cost of doing so.
Collapse
Affiliation(s)
- Guillaume Desjeux
- Service d'information médicale, HIA Desgenettes, Lyon Armées, France.
| | | | | |
Collapse
|
13
|
Charrel RN, Attoui H, Butenko AM, Clegg JC, Deubel V, Frolova TV, Gould EA, Gritsun TS, Heinz FX, Labuda M, Lashkevich VA, Loktev V, Lundkvist A, Lvov DV, Mandl CW, Niedrig M, Papa A, Petrov VS, Plyusnin A, Randolph S, Süss J, Zlobin VI, de Lamballerie X. Tick-borne virus diseases of human interest in Europe. Clin Microbiol Infect 2004; 10:1040-55. [PMID: 15606630 DOI: 10.1111/j.1469-0691.2004.01022.x] [Citation(s) in RCA: 207] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Several human diseases in Europe are caused by viruses transmitted by tick bite. These viruses belong to the genus Flavivirus, and include tick-borne encephalitis virus, Omsk haemorrhagic fever virus, louping ill virus, Powassan virus, Nairovirus (Crimean-Congo haemorrhagic fever virus) and Coltivirus (Eyach virus). All of these viruses cause more or less severe neurological diseases, and some are also responsible for haemorrhagic fever. The epidemiology, clinical picture and methods for diagnosis are detailed in this review. Most of these viral pathogens are classified as Biosafety Level 3 or 4 agents, and therefore some of them have been classified in Categories A-C of potential bioterrorism agents by the Centers for Disease Control and Prevention. Their ability to cause severe disease in man means that these viruses, as well as any clinical samples suspected of containing them, must be handled with specific and stringent precautions.
Collapse
Affiliation(s)
- R N Charrel
- Unité des Virus Emergents, Faculté de Médecine, Marseille, France.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Marth E, Kleinhappl B, Jelovcan S. Stimulation of the immune system by different TBE-virus vaccines. Int J Med Microbiol 2004; 293 Suppl 37:139-44. [PMID: 15146996 DOI: 10.1016/s1433-1128(04)80025-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Tick-borne encephalitis (TBE) is one of the most frequent arthropod-transmitted viral diseases in Europe. Different vaccines against TBE-virus have been developed; a thimerosal-free and also albumin-free vaccine [Ticovac (Baxter Hyland Immuno, Vienna)] was approved in 2000. Contrary to previous experience, 779 cases of fever occurred following the first vaccination of children under 15 years of age and in 62 children febrile convulsions were even observed. Consequently, the composition of the vaccine was changed and albumin was again added [FSME-Immun (Baxter Vaccines, Vienna)] in 2001. The new Encepur Kinder (Chiron-Behring, Marburg) from 2002 is a TBE-vaccine for children without any protein as stabilizer but with a relatively high concentration of sucrose, while the former vaccine Encepur K from 1991 contained polygeline as the stabilizer. The induction of the immune system by the different TBE virus vaccines was compared in an in vitro test in order to find an explanation for the unexpected fever attacks. Whole blood was stimulated with complete vaccine suspension, and TNF-alpha, IL-1beta, IL-6, and IL-8 were determined from heparin/EDTA-plasma and culture supernatants. It was shown that Ticovac and the new Encepur Kinder can induce relatively high amounts of TNF-alpha and lower amounts of IL-1beta. An increase of both cytokines was first observed following an incubation of 4 hours, with a maximum after 15 hours. Concentrations returned to base-line values within 26 hours. The behaviour of both cytokines correlates with the febrile phases in children up to two years old. Albumin or other proteins like polygeline and also immunoglobulins prevented a rise of cytokines.
Collapse
Affiliation(s)
- Egon Marth
- Institute of Hygiene of the University of Graz, Graz, Austria.
| | | | | |
Collapse
|
15
|
Abstract
The Flaviviridae is a family of arthropod-borne, enveloped, RNA viruses that contain important human pathogens such as yellow fever (YF), Japanese encephalitis (JE), tick-borne encephalitis (TBE), West Nile (WN), and the dengue (DEN) viruses. Vaccination is the most effective means of disease prevention for these viral infections. A live-attenuated vaccine for YF, and inactivated vaccines for JE and TBE have significantly reduced the incidence of disease for these viruses, while licensed vaccines for DEN and WN are still lacking despite a significant disease burden associated with these infections. This review focuses on inactivated and recombinant subunit vaccines (non-replicating protein vaccines) in various stages of laboratory development and human testing. A purified, inactivated vaccine (PIV) candidate for DEN will soon be evaluated in a phase 1 clinical trial, and a second-generation JE PIV produced using similar technology has advanced to phase 2/3 trials. The inactivated TBE vaccine used successfully in Europe for almost 30 years continues to be improved by additional purification, new stabilizers, an adjuvant, and better immunization schedules. The recent development of an inactivated WN vaccine for domestic animals demonstrates the possibility of producing a similar vaccine for human use. Advances in flavivirus gene expression technology have led to the production of several recombinant subunit antigen vaccine candidates in a variety of expression systems. Some of these vaccines have shown sufficient promise in animal models to be considered as candidates for evaluation in clinical trials. Feasibility of non-replicating flavivirus vaccines has been clearly demonstrated and further development is now warranted.
Collapse
Affiliation(s)
- Kenneth H Eckels
- Division of Communicable Diseases and Immunology, Walter Reed Army Institute of Research, Silver Spring, Maryland 20910, USA
| | | |
Collapse
|
16
|
Marth E, Kleinhappl B. Albumin is a necessary stabilizer of TBE-vaccine to avoid fever in children after vaccination. Vaccine 2001; 20:532-7. [PMID: 11672919 DOI: 10.1016/s0264-410x(01)00329-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A thiomersal-free and also an albumin-free tick-borne encephalitis-vaccine (TBE-vaccine) was developed. This vaccine was approved by the Austrian health authorities in the year 2000. Contrary to previous experience, 779 cases of fever attacks occurred following the first vaccination of children under 15 years of age. The induction of the immune system by different TBE virus (TBEV) vaccines (FSME-Immun [1999], Ticovac [2000] and FSME-Immun [2001] all from Baxter Hyland Immuno, Vienna) was compared in an in vitro immune stimulation test in order to find an explanation for the unexpected fever attacks. It was shown that only Ticovac, which contains no albumin as a stabilizer, can induce relative high amounts of TNF-alpha (P < or = 0.0001) and lower amounts of IL-1 beta (P < or = 0.05). Increase of both cytokines is first observed following an incubation of 4 h. The maximum is reached after 15 h. After 26 h, it has reverted to the original value. The course of concentration of both cytokines corresponds to the time of observed febrile phases. Albumin or immunoglobulin prevents a rise of cytokines so that it is recommended to add the albumin again to the vaccine.
Collapse
Affiliation(s)
- E Marth
- Institute of Hygiene of the University of Graz, Universitätspl.4, A-8010 Graz, Austria.
| | | |
Collapse
|
17
|
Abstract
This article reviews some of the issues involved in evaluating vaccines in humans. Vaccine trials are required for licensure and are essential for demonstrating a vaccine's safety and protective efficacy. The formal framework of phase I, II, and III trials is described, with particular emphasis on the choice of hypotheses, trial design, and biases that arise in the context of vaccine trials. However, some aspects of a vaccine's performance cannot be evaluated in clinical trials owing to their relatively small size. Thus, vaccine evaluation must continue after licensure, for example, to evaluate the vaccine with respect to rare reactions, duration of protection, and ecological effects. The article reviews some of the methods commonly used for post-licensure studies of vaccine efficacy and safety.
Collapse
Affiliation(s)
- C P Farrington
- Department of Statistics, Open University, Walton Hall, Milton Keynes MK7 6AA, England.
| | | |
Collapse
|
18
|
Abstract
BACKGROUND Tick-borne encephalitis is a disease of the central nervous system caused by a virus. Other than the vaccine, there is no treatment for the disease. OBJECTIVES The objective of this review was to assess the effects of vaccines to prevent tick-borne encephalitis. SEARCH STRATEGY We searched the Cochrane Infectious Diseases Group trials register, the Cochrane Vaccine Fields Trials Register, the Cochrane Controlled Trials Register, Medline, Embase and reference lists of articles. We also handsearched the journal Vaccine. SELECTION CRITERIA Randomised and quasi-randomised trials comparing tick-borne encephalitis vaccines against placebo, control vaccines or comparisons of different doses or schedules of tick-borne encephalitis vaccines. DATA COLLECTION AND ANALYSIS Two reviewers independently applied inclusion criteria. A panel of six assessors examined trial quality. MAIN RESULTS Five trials were included. They could not be combined for meta-analysis because of differences in comparisons and outcomes. Four types of tick-borne encephalitis vaccines were used. All the vaccines gave seroconversion rates of over 87%. There were frequent reports of systemic and local adverse effects. REVIEWER'S CONCLUSIONS Tick-borne encephalitis vaccines appear to be highly immunogenic, but the relationship between seroconversion and clinical protection has not been established. Although adverse effects were commonly reported, none were severe or life threatening.
Collapse
Affiliation(s)
- V Demicheli
- Dept of Preventive Medicine & Biometrics, University of Colorado Health Sciences Center, Box C 245, 4200 E Ninth Ave, Denver, CO 80262, USA.
| | | | | | | |
Collapse
|
19
|
Schmaljohn C, Custer D, VanderZanden L, Spik K, Rossi C, Bray M. Evaluation of tick-borne encephalitis DNA vaccines in monkeys. Virology 1999; 263:166-74. [PMID: 10544091 DOI: 10.1006/viro.1999.9918] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tick-borne encephalitis is usually caused by infection with one of two flaviviruses: Russian spring summer encephalitis virus (RSSEV) or Central European encephalitis virus (CEEV). We previously demonstrated that gene gun inoculation of mice with naked DNA vaccines expressing the prM and E genes of these viruses resulted in long-lived homologous and heterologous protective immunity (Schmaljohn et al., 1997). To further evaluate these vaccines, we inoculated rhesus macaques by gene gun with the RSSEV or CEEV vaccines or with both DNA vaccines and compared resulting antibody titers with those obtained by vaccination with a commercial, formalin-inactivated vaccine administered at the human dose. Vaccinations were given at days 0, 30, and 70. All of the vaccines elicited antibodies detected by ELISA and by plaque-reduction neutralization tests. The neutralizing antibody responses persisted for at least 15 weeks after the final vaccination. Because monkeys are not uniformly susceptible to tick-borne encephalitis, the protective properties of the vaccines were assessed by passive transfer of monkey sera to mice and subsequent challenge of the mice with RSSEV or CEEV. One hour after transfer, mice that received 50 microl of sera from monkeys vaccinated with both DNA vaccines had circulating neutralizing antibody levels <20-80. All of these mice were protected from challenge with RSSEV or CEEV. Mice that received 10 microl of sera from monkeys vaccinated with the individual DNA vaccines, both DNA vaccines, or a commercial vaccine were partially to completely protected from RSSEV or CEEV challenge. These data suggest that DNA vaccines may offer protective immunity to primates similar to that obtained with a commercial inactivated-virus vaccine.
Collapse
MESH Headings
- Animals
- Antibodies, Viral/blood
- Antigens, Viral/immunology
- Biolistics
- Drug Evaluation, Preclinical
- Encephalitis Viruses, Tick-Borne/immunology
- Encephalitis, Tick-Borne/immunology
- Encephalitis, Tick-Borne/prevention & control
- Europe
- Female
- Immunization, Passive
- Macaca mulatta
- Mice
- Mice, Inbred BALB C
- Neutralization Tests
- Russia
- Vaccination
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/immunology
- Vaccines, Inactivated/immunology
- Viral Vaccines/administration & dosage
- Viral Vaccines/immunology
Collapse
Affiliation(s)
- C Schmaljohn
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland 21702, USA.
| | | | | | | | | | | |
Collapse
|
20
|
Dengler TJ, Zimmermann R, Meyer J, Sack FU, Girgsdies O, Kübler WE. Vaccination against tick-borne encephalitis under therapeutic immunosuppression. Reduced efficacy in heart transplant recipients. Vaccine 1999; 17:867-74. [PMID: 10067693 DOI: 10.1016/s0264-410x(98)00272-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Patients after organ transplantation are at an increased risk of microbial infections and might benefit from active vaccination. Due to therapeutic immunosuppression the efficacy of immunizations is, however, reduced and difficult to predict. Efficacy of vaccination against tick-borne encephalitis (TBE) using an abbreviated immunization schedule was compared in 31 heart transplant recipients (age: 54.5 +/- 11.5 years, mean time after transplantation: 53.5 +/- 23.7 months) under cyclosporine-based immunosuppression and 29 controls. TBE vaccination was well tolerated by the transplant recipients; spectrum and frequency of adverse events were similar to controls. In the transplant patients, seroconversion rate (35% versus 100%; p < 0.001) and the geometric mean of post-vaccinal antibody titres (0.98 (SF: 2.3) U/ml versus 5.46 (2.2) U/ml; p < 0.001) were markedly reduced in comparison to the control group. No clinical or demographic predictors of vaccination success could be established in the transplant patients. Due to the limited efficacy, TBE vaccination cannot be recommended as a routine procedure in heart transplant recipients at risk of TBE virus infection. TBE vaccination may be performed safely in selected cases, but repeated titre controls to confirm vaccination success would be required.
Collapse
Affiliation(s)
- T J Dengler
- Department of Cardiology, University of Heidelberg, Germany
| | | | | | | | | | | |
Collapse
|
21
|
Günther G, Haglund M, Lindquist L, Sköldenberg B, Forsgren M. Intrathecal IgM, IgA and IgG antibody response in tick-borne encephalitis. Long-term follow-up related to clinical course and outcome. CLINICAL AND DIAGNOSTIC VIROLOGY 1997; 8:17-29. [PMID: 9248655 DOI: 10.1016/s0928-0197(97)00273-0] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Tick-borne encephalitis (TBE) of western subtype causes long-term morbidity and is considered a health problem in Scandinavia, eastern and central parts of Europe and Russia. The pathophysiology is not fully elucidated. As TBE RNA is rarely demonstrable in cerebrospinal fluid (CSF) the kinetics of the CSF antibody response to the disease has attracted attention. OBJECTIVES To investigate the intrathecal TBE-specific antibody response and to correlate its intensity and persistence to the clinical course. To compare indirect, commercially-based ELISA methods indexed against albumin ratio or IgG ratio with the capture ELISA method for the establishment of CSF response. STUDY DESIGN The specific IgM, IgG and IgA antibody responses in serum and CSF were analysed in 69 Swedish patients included in a prospective study of TBE from the acute phase up to 11-13 months after onset. RESULTS Antibody response by all three classes was demonstrable in serum and CSF. All methods were useful, but capture technique was the most sensitive and results were easiest to interpret. Peak IgM activity was seen early during the disease and persisted after 6 weeks. Maximum IgG levels were encountered in late convalescent samples (median 6 weeks). Intrathecal antibody production was demonstrable in nearly all patients: in 41% days 0-6, in 97% days 7-19, in 98% days 21-61 and-at lower levels-in 84% of the patients after 1 year (50/52 of CSF-serum sampled in the interval 11-61 days). Day 9 after onset, patients with dominating encephalitic symptoms showed significantly lower intrathecal IgM activity. The persistence of serum and CSF antibodies did not correlate to severity of disease. CONCLUSIONS Capture IgM and IgG assays were superior to indirect ELISA. Low early CSF IgM response correlated to encephalitic symptoms, otherwise the intensity and duration of intrathecal antibody response were of limited value for the prediction of clinical course and long-term outcome.
Collapse
Affiliation(s)
- G Günther
- Department of Infectious Diseases, Karolinska Institute, Danderyd Hospital, Sweden
| | | | | | | | | |
Collapse
|
22
|
Abstract
This paper describes the planning, implementation, and analysis of a clinical trial to develop a pediatric vaccine against the tick-borne encephalitis virus. The trial was primarily a dose-finding study with the following objectives: the protein content of the vaccine should be lower than that of the vaccine for adults (which was already approved) in order to reduce reactogenicity, especially the rate of fever reactions, in children. At the same time, the protein content had to be high enough so that the immunogenicity of the pediatric vaccine would be at least equivalent to that of the vaccine for adults. We discuss in detail the definition of the equivalence criterion and the considerations concerning sample size calculation. The methods described in this paper are also useful for designing clinical trials for the development of combined vaccines.
Collapse
|
23
|
Bock HL, Löscher T, Scheiermann N, Baumgarten R, Wiese M, Dutz W, Sänger R, Clemens R. Accelerated Schedule for Hepatitis B Immunization. J Travel Med 1995; 2:213-217. [PMID: 9815393 DOI: 10.1111/j.1708-8305.1995.tb00661.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Background: A considerable number of people remain unprotected against hepatitis B. These people may require immunization at short notice before being exposed to situations or locations where a risk of infection is present. Currently, full active immunization against hepatitis B, when administered according to recommended schedules, takes 2-6 months. This open, randomized multicentric study evaluated the reactogenicity and immunogenicity of a recombinant hepatitis B vaccine in adults when it was administered according to three different rapid vaccination schedules. Methods: Five hundred and twenty four healthy adults (aged 18-59 years) were randomly divided into three groups. Hepatitis B vaccine was given intramuscularly in the deltoid muscle at months 0, 1, and 2 (group A); weeks 0, 14, and 28 (group B); and weeks 0, 7, and 21 (group C). Symptoms were recorded by the subjects on individual diary cards. AntiHBs were measured using radioimmunoassay (Ausab-Abbott); a seroprotective titer was defined as 10 IU/L. Results: At day 28, no significant difference in seroprotection rates (SPRs) i.e., seroconversion >= 10 IU/L,was observed, between groups B (55.6%) and C (65.2%), but both these groups had significantly greater SPRs than group A (15.0%). Although not significant (p=.07), groups B and C also had higher SPRs than group A (78.5% and 76.4% versus 65%) at day 56. One month after completing the three dose schedules, the SPRs were as follows: 89.0% (group A); 78.5% (group B); and 76.4% (group C), increasing to > 94% at month 7 to 8 in all three groups. The SPRs at month 13 were 95.8%, 98.9%, and 98.6%, respectively. Among the three groups, no significant differences were observed from month 2 onwards in either SPRs or geometric mean titers. In groups A, B, and C, 3.7%, 5.0%, and 7.1% of the vaccine injections were associated with local symptoms. Also 8.3%, 6.2%, and 6.3% of subjects exhibited general symptoms following each vaccine dose; all symptoms were transient and resolved spontaneously. Conclusions: This recombinant hepatitis B vaccine administered at weeks 0, 7, 21, or at weeks 0, 14, 28, rapidly elicits high rates of seroprotection, which persist at least until month 12.
Collapse
Affiliation(s)
- HL Bock
- SmithKline Beecham Pharma, Munich, Germany
| | | | | | | | | | | | | | | |
Collapse
|
24
|
Harabacz I, Bock H, Jüngst C, Klockmann U, Praus M, Weber R. A randomized phase II study of a new tick-borne encephalitis vaccine using three different doses and two immunization regimens. Vaccine 1992; 10:145-50. [PMID: 1557929 DOI: 10.1016/0264-410x(92)90003-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A new, highly purified inactivated tick-borne encephalitis (TBE) vaccine (FSME-Vaccine Behring, BI 71.061) was recently registered in Germany. A multinational phase II study was performed in seven centres located in areas endemic for TBE. A total of 379 healthy adults were randomly allocated into three dosage groups (1.0, 1.5 and 2.0 micrograms antigen per dose, respectively) and into two immunization schedules [vaccination with one dose of 0.5 ml intramuscularly on days 0, 7 and 21 (abbreviated schedule), or on days 0, 28 and 300 (conventional schedule)]. Antibody response to vaccination was assayed by enzyme-linked immunosorbent assay (ELISA), haemagglutination inhibition test (HIT) and neutralization test (NT). Seroconversion rates in the different groups 28 days after one single dose were 75.3-83.5% in ELISA, 35.8-50.6% in HIT, and 100% in NT. All vaccinees showed seroconversion in all tests on day 42 in the conventional schedule and on day 35 in the abbreviated schedule, with the exception of one subject, who remained seronegative in HIT only. Geometric mean titres (GMT) of about 3000 in ELISA were achieved by two vaccinations in the conventional schedule and showed a booster increase to 5500-8000 GMT after revaccination on day 300. Overall frequency of adverse events (related and unrelated) was 37% (conventional schedule) and 46% (abbreviated schedule) after the first, 9% and 21% after the second, and 5% and 15% after the third vaccination, respectively. Generally, side effects were mild and transient, including mainly headache, fever, malaise and local irritation. Serious, vaccine-related side effects did not occur.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
|