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Chapter 13: TBE as a matter of public health

‘incidence threshold’ is used as a particularly if long-term sequelae and
condition before TBE risk is communicat- social costs are not accounted for. The
ed. Thus, lack of case finding and case prerequisite for a vaccination program to
reporting results in missed opportunities be effective is a high vaccine uptake and
for prevention. this requires appropriate funding not only
for the vaccine but also for its administra-
3. With vaccine uptake being unknown in tion. The results then of such a program
many instances, reporting case incidences are ‘no disease’ – and absence of diseases
results in artificially low numbers and thus is not a success story in the popular media
an underestimation of true TBE risk. or in elections unless rigorous (and again
expensive) surveillance is undertaken to
4. The risk of TBEV infection is influenced by assess field effectiveness and document
seasonal patterns of tick bites and the success. Valid surveillance again needs
transmission, the environment, personal appropriate funding – and so another
behavior, personal protection measures
vicious cycle emerges, where a perceived
and, of course, (vaccination-induced) ‘rare disease’ is not considered to justify
immunity. The details of the interactions or even be eligible for public health
among all parameters (reservoir animals, expenditures.
tick activity, migrating birds, climate, the
environment/landscape and its changes 8. Finally, public health officials often
over time, human behavior, etc.) and the become more active largely when there
resulting risk for TBE is largely unknown to are common threats, and symptomatic
date and – due to the complexity – TBE is relatively rare (see Chapter 11b).
difficult to assess. Moreover, TBE vaccination results in
individual protection only and not in any
5. The risk of TBE disease in general and the
herd protection (TBEV is not transmitted
severity of specific symptoms depend on between humans). So, while TBE
age, immunological status, underlying vaccination is highly effective, it does not
diseases/comorbidities, routine medica- result in any impact on the population in
tions, TBEV viral load, and the specific TBE
general; thus TBE vaccination is often not
strain. Not only has the epidemiology of
paid for by public health resources.
TBE posed issues for public health officials,
but it also appears fair to state that 9. We strongly believe – against all these
perhaps with the exception of Austria, TBE arguments and despite the so-called low
is 1) largely underreported and 2) mostly incidence of TBE – that this disease
neglected by public health authorities. deserves a high level of public health
Several reasons may explain this phe- attention because it poses a risk to any
nomenon: human living in or traveling to TBE
endemic areas and because the disease
6. TBE vaccination results in protection of may frequently result in long-term
the individual only. There is no herd
disability and, in some cases, even death.
protection because the viral reservoir Rightfully so, the public should be
exists outside the human population and concerned and, if correctly informed,
TBE is not transmitted between humans. would certainly opt for an adequate public
health response.
7. Classical TBE infection (i.e., infection
involving the CNS) is relatively rare, so

cost-benefit analyses are likely negative,

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