Recommendations for tick-borne encephalitis vaccination from the Central European Vaccination Awareness Group (CEVAG)

Abstract

Tick-borne encephalitis (TBE) is a viral neurological zoonotic disease transmitted to humans by ticks or by consumption of unpasteurized dairy products from infected cows, goats, or sheep. TBE is highly endemic in areas of Central and Eastern Europe and Russia where it is a major public health concern. However, it is difficult to diagnose TBE as clinical manifestations tend to be relatively nonspecific and a standardized case definition does not exist across the region. TBE is becoming more important in Europe due to the appearance of new endemic areas.Few Central European Vaccination Awareness Group (CEVAG) member countries have implemented universal vaccination programmes against TBE and vaccination coverage is not considered sufficient to control the disease. When implemented, immunization strategies only apply to risk groups under certain conditions, with no harmonized recommendations available to date across the region. Effective vaccination programmes are essential in preventing the burden of TBE. This review examines the current situation of TBE in CEVAG countries and contains recommendations for the vaccination of children and high-risk groups.For countries at very high risk of TBE infections, CEVAG strongly recommends the introduction of universal TBE vaccination in children > 1 y of age onwards. For countries with a very low risk of TBE, recommendations should only apply to those traveling to endemic areas. Overall, it is generally accepted that each country should be free to make its own decision based on regional epidemiological data and the vaccination calendar, although recommendations should be made, especially for those living in endemic areas.

Recommended immunization schedules for adults: Clinical practice guidelines by the Escmid Vaccine Study Group (EVASG), European Geriatric Medicine Society (EUGMS) and the World Association for Infectious Diseases and Immunological Disorders (WAidid)

“…[47][48][49] High vaccination coverage may decrease significantly TBE incidence, as it was proven in Austria. 48 At least 2 doses of TBE vaccine are required for development of protection.…”

“…47,48 No clinical trials have been conducted to determine the efficacy of TBE vaccines, but the effectiveness and safety of current vaccines has been proven in a number of observational studies. [47][48][49] In Austria, high vaccination coverage has led to a significant decrease in TBE incidence. 48 The overall field effectiveness in regularly vaccinated persons is approximately 99%, with no statistically significant difference between age groups, 49 It is at least as high after the first 2 vaccinations, i.e., before the completion of the basic vaccination scheme by a third vaccination, but is significantly lower (approximately 95%) in those with a record of irregular vaccination.…”

“…[47][48][49] In Austria, high vaccination coverage has led to a significant decrease in TBE incidence. 48 The overall field effectiveness in regularly vaccinated persons is approximately 99%, with no statistically significant difference between age groups, 49 It is at least as high after the first 2 vaccinations, i.e., before the completion of the basic vaccination scheme by a third vaccination, but is significantly lower (approximately 95%) in those with a record of irregular vaccination. TBE break-through infections are reported rarely and primarily occur in older age groups.…”

“…TBE vaccine failure infections are reported rarely. 49 In areas where the disease is highly endemic ( 5 cases/ 100,000 per year), implying that there is a high individual risk of infection, World Health Organization recommends vaccination of all age groups. 50 The primary vaccination series consists of 3 doses (day 0, 1 to 3 months after the first dose, 5 to 12 months after the second dose) and booster dose should be administered every 5 y, in Switzerland even every 10 y.…”

“…50 The primary vaccination series consists of 3 doses (day 0, 1 to 3 months after the first dose, 5 to 12 months after the second dose) and booster dose should be administered every 5 y, in Switzerland even every 10 y. 49 If a rapid immune response is required, accelerated schedule based on immunization on day 0, day 14 and month 5-7, or on day 0, day 7 and day 21 according to vaccine may be used.…”