Dr. Murai Éva - Gubányi András szerk.: Parasitologia Hungarica 29-30. (Budapest, 1997)

regions. The inoculation provides protection only if it is administered within 96 hours of the tick bite. Even in that case, the rate of protection is only 75%. When administered after day 4 as from the tick bite, FSME-Bulin is surely ineffective. Therefore, when justified, it should be administered as soon as possible. Its dose increases in direct proportion to the body weight and to the time that has elapsed since the tick bite. Within two days as of the tick bite, the dose is 0.1 ml per kg of body weight, while on days 3 - 4 it is twice higher. A corpulent man may require a dose as large as 20 ml. The administration of this preparation should be carefully considered (Aebi and Schaad 1994), but it can be given also before the expected tick bite, if there is not enough time for active immunisation. The duration of the protective effect is only one month. Vaccination is not recommended for three months after the administration of TBE immunoglobulins, as the latter impairs the efficiency of active immunisation (Hederström et al. 1995). Following active immunisation, the vaccinated persons themselves will produce the protective antibodies. The advantage of active immunisation that it provides lasting protection, while the drawback is that with vaccines prepared from inactivated virus multiple injections are needed for inducing and maintaining immunity. One of the available vaccines is FSME-Immun-Inject (Immuno) which was developed in 1993 and has been commercially available since 1976. This vaccine has been used for immunising persons at risk of TBE on account of their occupation since 1977. The vaccine has been available to anyone since 1991. As it contains inactivated virus, there are practically no dangerous side effects. In a few cases a rise in temperature, fever, local infiltration, headache or possibly articular pain may occur. These adverse events occur mostly after the first injection, they are much less common after the second injection and completely absent after the third one. Vaccines of different batch numbers have been shown to differ markedly in terms of the vaccination reactions induced (Vlasimska and Smejkalova 1995). No serious adverse events have been encountered. Two years ago a great scare was created by the suddenly increased number of reactions involving high fever; however, no serious complications occurred. As adverse events characterised by high fever were observed mainly in small children, the use of the vaccine in children below 6 years of age must be carefully considered. Earlier, the manufacturer prohibited the use of the vaccine in periods characterised by a high risk of tick bites, as infections acquired at the time of vaccination could have appeared to be vaccination reactions. Today such restrictions no longer exist, which means that vaccination may be started in any period of the year; however, it is advisable to choose the winter months. It must not be forgotten that a prolonged protection can safely be induced only by a basic immunisation consisting of a series of three injections. A booster injection is needed every three years. If the tick bite occurs at least four days after the first vaccination but before the planned second injection, the second dose must be administered immediately to induce satisfactory protection. Last year a new vaccine was put into circulation by the name of Encepur (Behring). This preparation also serves for active immunisation. It has some advantageous properties: it does not contain human proteins and a mercury-containing preservative which could elicit an allergic reaction. It can be administered according to two different schemes. The manufacturer developed a rapid immunisation protocol which provides protection already by day 21 (Harabacz et al. 1992). Using that protocol, an injection each must be administered on days 0, 7 and 21, and then in the 18th month. The other vaccination scheme is