Page 439 - TBE_Book_V2_2019

Chapter 13: TBE as a matter of public health

Vector control squeezing the body, which could result in an
increased influx of pathogens. Not
As with other vector-borne diseases, strate- recommended are any attempts to drown a
gies to reduce vector density have been tick by bathing or using ‘home remedies’ like
implemented in the past. From the beginning suffocating a tick with a drop of glue, nail
of the 1950s to the end of the 1970s, this was polish, or oil, or burning it with a match or lit
the leading strategy of TBE prevention in cigarette. According to most authors, any
10
Russia. However, these large-scale control advantage offered by the seemingly easier
measures using tetrachlorvinphos, DDT, or removal of the tick is by far outweighed by the
Hexachlor did not produce the desired effect: disadvantage of an increased burden of
no significant impact was observed on human infectious particles being released while the
infections. Since the virus persists not only in tick is struggling to death.
ticks, but also in a large number of wild
animals, particularly small mammals, such To overcome another misconception: if a
measures are unlikely to eradicate or even black dot should happen to remain in the
11
control the disease. wound after tick removal, this is not the head
of the tick but some part of the biting
Secondary prophylaxis apparatus only. Taking into account the
anatomy of the tick as an arachnid, the head
(Early) tick detection and removal and specifically biting apparatus are sources of
infection (and in the case of TBEV, the salivary
Ticks do not immediately penetrate the skin of
glands). Once these are safely removed by the
the host. Some time is always required until
recommended actions and even if these
the tick finds the most appropriate location
resulted in incomplete removal, the window
for its bite. After the tick bite, TBEV is of TBEV transmission certainly would be
immediately transmitted to the host by means closed. In summary, all preventive measures
of the tick’s saliva. Even if the tick is already
described above and directed against ticks
firmly attached to the skin, early removal is
offer only limited protection. This reinforces
still advised to help to avoid other potential the need for vaccine protection. A summary of
infections like those with Borrelia spp., where prevention recommendations is provided in
transmission of bacteria takes place between Table 1.
1 and 3 days after the tick has attached itself
to a human host. Thus, if a tick is detected and
immediately removed after attachment, the Cost-benefit analysis of TBE
risk of certain infections in humans is reduced
12
substantially. vaccination
Tick removal should follow a number of rules: Although cost-benefit analyses are often
screening the body after outdoor activities is closely linked to official recommendations for
20
always an important first measure. Adherent vaccination, this aspect is of limited value
ticks should be removed as atraumatically as when it comes to a disease that often leads to
possible (https://amp.usatoday.com/amp/ chronic sequelae and even death but on the
2189393002). other hand can be easily prevented. Here,
ethical considerations are the main issue: cost
This can be done using a fine- tipped tweezer, -benefit calculations are applicable if more
long fingernails, or special cards. The key is to than one option (vaccination) is available and
pick the tick at the part closest to the skin and the individual is able to choose between
to tear it off without rotation and without different and equally effective strategies.

434
441