View clinical trials related to Encephalitis, Tick-borne.
Filter by:In Slovenia, tick-borne encephalitis and Lyme borreliosis are both endemic diseases with high incidence rates and they are both transmitted by a bite of infected Ixodes ricinus tick. In clinical practice, tick-borne encephalitis is confirmed by demonstration of tick-borne encephalitis antibodies in serum of a patient with compatible clinical presentation and cerebrospinal pleocytosis. Patients with Lyme meningitis or meningoradiculitis also have cerebrospinal pleocytosis, however the presence of borrelial antibodies in serum does not attest Lyme neuroborreliosis. Patients with tick-borne encephalitis and positive borrelial antibodies in serum, but not fulfilling criteria for Lyme neuroborreliosis, are often being treated with antibiotics in several European countries due to the possibility of double infection. The investigators hypothesise that such patients do not benefit from antibiotics. Such an approach may appear safe regarding the possibility of borrelial infection, however it can also be associated with detrimental consequences such as antibiotic related adverse reactions, negative epidemiological impact on bacterial resistance, and intravenous catheter related complications.
The risk for tick borne encephalitis increases in Sweden. Together with an increased awareness of the possibility to acquire protection by vaccination, this has led to an increase in the number of doses of the vaccine distributed in Sweden each year - now being approximately 400.000. The first year, two doses with an interval of 1 month is recommended for the general population, followed by a third dose approximately one year later and an additional booster dose three years after the third. Preliminary results from a previous study showed a higher percentage protected (=titer at least 10) after 3 doses than after 2 doses (Rombo et al. EUDRA CT 2011 001348-31, unpublished information). In the same study, there were no differences between those who were vaccinated 0+7+21 compared to 0+30+90. The investigators were surprised to find marked differences between 2 and 3 doses also in the younger control group. The investigators therefore aim to confirm results in a new study and to add a group with a double dose at day 0 and then a single dose at day 30 and 360
Patients undergoing allogeneic blood and marrow transplantation (HSCT) experience a prolonged period of dysfunctional immunity. Systematic reimmunization is necessary at appropriate time intervals following transplantation to re-establish immunity. Vaccination practices after HSCT remain varied and data sparse. Tick-borne encephalitis (TBE) is one of the most severe infections of the central nervous system caused by a tick-borne flavivirus. There is no specific treatment, and prevention with the vaccine is the only intervention available. To assess the efficacy of TBE vaccination in adult allogeneic HSCT recipients compared to an age-matched and sex-matched control group of healthy volunteers without previous TBE vaccination, a prospective open-label phase II pilot study on humoral and cellular immune responses after use of TBE vaccine (FSME Immun) will be performed. As primary end point the outcome of the neutralization test (NT) against TBE will be assessed in a total of 26 HSCT patients one year after HSCT and in 26 healthy volunteers, namely four weeks after the second vaccination. Therefore, the number of subjects with NT titres against TBE virus >10, assumed to be the threshold for antibody-mediated protection will be evaluated. As secondary endpoints, antibody concentrations of TBE enzyme-linked immunosorbent assay before and four weeks after the second and third vaccination and antibody concentrations of NT against TBE four weeks after primary immunization. To evaluate cellular immune responses, lymphocyte proliferations assays and cytokine detection assays will be performed. In a subgroup analysis, these secondary endpoints will be compared between healthy volunteers, HSCT patients without immunosuppressive treatment and HSCT patients receiving immunosuppressive agents. Additionally, immune reconstitution by analysis of peripheral blood lymphocyte subsets and serum immunoglobulin levels will be evaluated prior to vaccination, after twelve weeks and prior to the third vaccination in HSCT patients only.
Many viral infections of global importance, including HIV, are transmitted across the mucosal surface of the genital tract. As immunity against these infections is likely to be primarily mediated by antibodies in mucosal secretions, developing techniques to increase the levels and persistence of antiviral antibody on mucosal surfaces may enhance the protection against a number of important infections. Preclinical studies have anatomically targeted vaccine antigens to sites where genital tract immunity is induced. This response is likely due to the ability of regional lymph Preclinical studies have anatomically targeted vaccine antigens to sites where genital tract immunity is induced. This response is likely due to the ability of regional lymph nodes to "pattern" the cell surface markers of responding vaccine specific lymphocytes with homing markers. In contrast, injecting a distant muscle (such as in the arm) which shares no anatomical relationship with the vagina, may not pattern cells with homing markers for the genital tract. Direct injection of inguinal lymph nodes is impractical in humans but intramuscular injection into the thigh will target antigens to the deep inguinal lymph nodes shared in common with the cervix/vagina. This study will be a Phase IV randomised, single centre, open label, laboratory assessment blinded exploratory trial to assess mucosal immunogenicity following three targeted intramuscular immunisations with TicoVac vaccine. 20 subjects will be randomised to each of2 groups immunised in right deltoid or right anterolateral thigh. Following an initial screening visit subjects will be immunised at 0, 1 and 6 months. There will be follow up visits 5 days after each immunisation and a final visit at 7 months. Blood samples and cervicovaginal secretions will be taken prior to each immunisation for immunological measures. In addition, blood samples will be taken at each immunisation and follow up visit for measurement of peripheral blood mononuclear cells. The study is funded by ADITEC, which is a collaborative research programme that aims to accelerate the development of novel and powerful immunisation technologies for the next generation of human vaccines.
The purpose of this study is to evaluate TBE antibody persistence from 7 to 10 years after the first booster TBE vaccination with FSME-IMMUN 0.5ml.
The aim of this study is to investigate the immunogenicity response in adults up to 10 years after one booster dose. Data collected from this study will allow for greater information to prescribers who administer TBE vaccine, so that they can appropriately time the administration of booster vaccinations to individuals who received different vaccination schedules and who live in tick borne encephalitis endemic regions.
Antibody titers after tick-borne encephalitis (TBE) vaccination are less in elderly and vaccination breakthroughs are more common in this age group. This has prompted Swedish authorities to recommend an additional dose in the initial vaccination schedule (= 0+30+90 days instead of the usually recommended 0+30 days. The investigators intend to evaluate this regime.
This study will evaluate the durability of antibody responses in children and adolescents after primary immunization with TBE vaccine
This was an open label trial of a non-US licensed vaccine for tick-borne encephalitis. The vaccine was licensed by Baxter, and now following an acquisition by Pfizer Inc in Vienna, Austria since 2001, and has an extensive safety record in multiple European countries. Field effectiveness studies suggest > 99 percent protection against disease transmitted by the natural routes of either tick bite or ingestion of contaminated, unpasteurized milk. The vaccine is also considered to be effective against laboratory exposures and is used routinely for this purpose in European laboratories. The US Centers for Disease Control and Prevention and the National Institutes of Health acknowledge the effectiveness of the vaccine by allowing those who have received it to study tick-borne encephalitis virus (TBEV) in isolation facilities rated at BSL-3 rather than the more stringent BSL-4, with the exception of the Russian Spring-Summer Encephalitis strain. Subjects were recruited from personnel at 2 intramural campuses of the National Institute of Allergy and Infectious Diseases who may be exposed accidentally to any strain or serotype of viable TBEV. Approximately 160 individuals were eligible to participate. The rapid immunization schedule (injections on Days 0, 14, and 161) was used and subjects had labs drawn 21 days after the 2nd, 3rd and 4th vaccine injections to determine seroconversion. Subjects that seroconverted to TBEV were offered a booster dose of the vaccine 3 years from the date of receipt of the third dose of the vaccine. Subjects that were seropositive at entry into the study were offered a booster dose of the vaccine every 3 years from Day 0.
The purpose of this study is to assess clinical outcome in patients with tick borne encephalitis.