Vaccine failures after active immunisation against tick-borne encephalitis

Tick-borne encephalitis virus (TBEV), a member of the family Flaviviridae, is one of the most important tick-transmitted viruses in Europe and Asia. Being a neurotropic virus, TBEV causes infection of the central nervous system, leading to various (permanent) neurological disorders summarized as tick-borne encephalitis (TBE). The incidence of TBE cases has increased due to the expansion of TBEV and its vectors. Since antiviral treatment is lacking, vaccination against TBEV is the most important protective measure. However, vaccination coverage is relatively low and immunogenicity of the currently available vaccines is limited, which may account for the vaccine failures that are observed. Understanding the TBEV-specific correlates of protection is of pivotal importance for developing novel and improved TBEV vaccines. For affording robust protection against infection and development of TBE, vaccines should induce both humoral and cellular immunity. In this review, the adaptive immunity induced upon TBEV infection and vaccination as well as novel approaches to produce improved TBEV vaccines are discussed.

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TBE Vaccination Breakthrough Cases—Does Age Matter?

Vaccines ◽

10.3390/vaccines9080932 ◽

2021 ◽

Vol 9 (8) ◽

pp. 932

Author(s):

Heinz-J. Schmitt ◽

Gerhard Dobler ◽

Dace Zavadska ◽

Zane Freimane ◽

Dimitrios Fousteris ◽

...

Keyword(s):

Age Distribution ◽

Age Groups ◽

The Other ◽

Vaccine Uptake ◽

Priming Dose ◽

Southern Germany ◽

Diagnostic Practices ◽

Tick Borne Encephalitis ◽

Vaccine Failures ◽

Scientific Rationale

Tick-borne encephalitis (TBE) vaccines are highly effective in preventing TBE and vaccine failures (VF) are rare events. In this study, we compared the age distribution of TBE cases and TBE VF in three endemic countries: Sweden, Southern Germany, and Latvia. While the age distribution of TBE cases was similar for those <50 years versus those ≥50 years in all three countries, in Sweden, a higher proportion of VF cases was ≥50 years, whereas most VF cases in Latvia were <50 years of age and more evenly distributed between those <50 years versus those ≥50 in Southern Germany. Here, theoretical explanations were provided, including differences in diagnostic practices, vaccine uptake between age groups, behavioral patterns and underlying medical conditions, as to why VF were generally older in Sweden than the other countries. There is no scientific rationale to give an extra priming dose of TBE vaccine to subjects ≥50 years of age.

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Tick-borne Encephalitis Vaccine Failures: A 10-year Retrospective Study Supporting the Rationale for Adding an Extra Priming Dose in Individuals Starting at Age 50 Years

Clinical Infectious Diseases ◽

10.1093/cid/ciz176 ◽

2019 ◽

Vol 70 (2) ◽

pp. 245-251 ◽

Cited By ~ 14

Author(s):

Karin E Hansson ◽

Anja Rosdahl ◽

Mona Insulander ◽

Sirkka Vene ◽

Lars Lindquist ◽

...

Keyword(s):

Communicable Disease ◽

Vaccine Dose ◽

Vaccination Schedule ◽

Priming Dose ◽

Vaccine Failure ◽

Stockholm County ◽

Tick Borne Encephalitis ◽

Vaccination Recommendations ◽

Control And Prevention ◽

Vaccine Failures

Abstract Background Southern Sweden is endemic for tick-borne encephalitis (TBE), with Stockholm County as one of the high-risk areas. Our aim in this study was to describe cases of vaccine failures and to optimize future vaccination recommendations. Methods Patients with TBE were identified in the notification database at the Department of Communicable Disease Control and Prevention in Stockholm County during 2006–2015. Vaccine failure was defined as TBE despite adherence to the recommended vaccination schedule with at least 2 doses. Clinical data were extracted from medical records. Results A total of 1004 TBE cases were identified, 53 (5%) were defined as vaccine failures. In this latter group, the median age was 62 years (6–83). Forty-three (81%) patients were aged >50 years and 2 were children. Approximately half of the patients had comorbidities, with diseases affecting the immune system accounting for 26% of all cases. Vaccine failures following the third or fourth vaccine dose accounted for 36 (68%) of the patients. Severe and moderate TBE disease affected 81% of the cases. Conclusions To our knowledge, this is the largest documented cohort of TBE vaccine failures. Vaccine failure after 5 TBE vaccine doses is rare. Our data provide rationale for adding an extra priming dose to those aged ≥50 years.

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TBE in Estonia

Tick-borne encephalitis - The Book ◽

10.33442/978-981-14-0914-1_12b-10 ◽

2019 ◽

Author(s):

Kuulo Kutsar

Keyword(s):

Endemic Area ◽

Endemic Country ◽

Tick Borne Encephalitis ◽

Vertebrate Hosts

The first cases of tick-borne encephalitis (TBE) in Estonia were identified in 1949. Today, Estonia is a TBE-endemic country. A TBE-endemic area in Estonia is defined as an area with circulation between ticks and vertebrate hosts as determined by detection of TBEV or the demonstration of autochthonous infections in humans or animals within the last 20 years.

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Tick-borne encephalitis - The Book

10.33442/978-981-14-0914 ◽

2020 ◽

Keyword(s):

Tick Borne Encephalitis

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CHAPTER 9: Immunology of TBEV-Infections

Tick-borne encephalitis - The Book ◽

10.33442/26613980_9-3 ◽

2020 ◽

Keyword(s):

Central Nervous System ◽

T Cells ◽

Cerebrospinal Fluid ◽

Nervous System ◽

Nk Cells ◽

Peripheral Blood ◽

Sample Collection ◽

Tick Borne Encephalitis ◽

Viral Infectious Disease ◽

The Central Nervous System

Tick-borne encephalitis (TBE) is a viral infectious disease of the central nervous system caused by the tick-borne encephalitis virus (TBEV). TBE is usually a biphasic disease and in humans the virus can only be detected during the first (unspecific) phase of the disease. Pathogenesis of TBE is not well understood, but both direct viral effects and immune-mediated tissue damage of the central nervous system may contribute to the natural course of TBE. The effect of TBEV on the innate immune system has mainly been studied in vitro and in mouse models. Characterization of human immune responses to TBEV is primarily conducted in peripheral blood and cerebrospinal fluid, due to the inaccessibility of brain tissue for sample collection. Natural killer (NK) cells and T cells are activated during the second (meningo-encephalitic) phase of TBE. The potential involvement of other cell types has not been examined to date. Immune cells from peripheral blood, in particular neutrophils, T cells, B cells and NK cells, infiltrate into the cerebrospinal fluid of TBE patients.

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TBE in Croatia

Tick-borne encephalitis - The Book ◽

10.33442/26613980_12b7-3 ◽

2020 ◽

Keyword(s):

Tick Species ◽

Limited Data ◽

Notifiable Disease ◽

Genetic Characteristics ◽

Central European ◽

Tick Borne Encephalitis ◽

Tbe Virus ◽

Endemic Areas ◽

European Subtype

Even though tick-borne encephalitis (TBE) has been a notifiable disease in Croatia since 2007, there are no or only limited data available on the occurring tick species in the endemic areas, on the prevalence of TBE virus (TBEV) in ticks, its distribution in Croatia, and its genetic characteristics. Reporting of human cases also is very scarce. The Central European subtype of virus (TBEV-EU) appears to be present in Croatia

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TBE in South Korea

Tick-borne encephalitis - The Book ◽

10.33442/978-981-14-0914-1_12b-31 ◽

2019 ◽

Author(s):

Joon Young Song

Keyword(s):

South Korea ◽

Human Case ◽

Encephalitis Virus ◽

Surveillance Studies ◽

Tick Borne Encephalitis ◽

Tick Borne Encephalitis Virus

Although no human case of tick-borne encephalitis (TBE) has been documented in South Korea to date, surveillance studies have been conducted to evaluate the prevalence of tick-borne encephalitis virus (TBEV) in wild ticks.

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TBE in Slovakia

Tick-borne encephalitis - The Book ◽

10.33442/978-981-14-0914-1_12b-29 ◽

2019 ◽

Author(s):

Jana Kerlik

Keyword(s):

Encephalitis Virus ◽

Tick Borne Encephalitis ◽

Tick Borne Encephalitis Virus

The former Czechoslovak Republic was one of the first countries in Europe where the tick-borne encephalitis virus (TBEV) was identified.

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TBE in Poland

Tick-borne encephalitis - The Book ◽

10.33442/978-981-14-0914-1_12b-25 ◽

2019 ◽

Author(s):

Katarzyna Pancer ◽

Włodzimierz Gut

Keyword(s):

World War Ii ◽

Typhoid Fever ◽

Clinical Symptoms ◽

World War ◽

Tick Borne Encephalitis ◽

Northeastern Poland

Clinical symptoms of tick-borne encephalitis (TBE) were first described in Poland in 1948 by Demiaszkiewicz. All patients had been living in the Białowieża region (in northeastern Poland). Similar infections were described to those that had been diagnosed in the same region before World War II as complicated cases of typhoid fever or influenza.

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