Dr. Murai Éva szerk.: Parasitologia Hungarica 24. (Budapest, 1991)

month of pregnancy in the third woman. Two newborns' sera were tested for Bb. Both of them contained specific IgG antibody (1:64 and 1:128) but neither of the newborns showed clinical signs of infection. Screening tests The cut-off level was based on testing sera from 200 blood donors. Moreover, 516 inhabitants from Budapest and 224 residents from Veszprém county, as well as 125 infants with enteritis were tested. Of them 6%, 4.5% and 2.3% proved to be positive. Among the infants, no antibody titer above 1:128 was found. Epidemiology In Figure 7, the number of tested patients can be seen in yearly distribution. As the disease became well known in Hungary, more requests for borrelia antibody testing arrived. The number of tested patients increased exponentially, but the proportion of Lb cases decreased year by year. Frequency of symptoms The three main symptoms are shown in Figure 8. Only frank arthritis is included here. It is important to underline that 20% of our patients had more than one major symptom consecutively or at a time (Fig. 9). In many cases, this complex clinical picture led to the suspicion of Lb. There was a group of patients which could not be enrolled into any of the nine major symptoms. This group was not processed in the further statistical calculations. The importance of ECM is outstanding in diagnosing Lb. In Figure 10, only cases with complicated ECM and their accompanying symptoms are shown. The frequency of joint manifestations is impressive. Tick bite and its occurrence Hungary is divided into 64 equal squares along the latitudes and longitudes in Figure 11. Those patients are represented here who had information about the geographical place of tick bite. The bars are proportional to the number of tick bites in each square and they roughly draw the relief map of Hungary. Half of those patients who had noticed a tick bite were proved to have borrelia infection. Our data suggest that Lb is prevalent in every area of Hungary where ixodid ticks can be found. Many patients were bitten by a tick in their own garden in Budapest. In our material altogether 886 patients noticed tick bite, and 932 did not. Information about tick bite has not been registered in one-third of our patients (Fig. 12). One-fifth of Lb cases did not notice tick bite. The frequency of tick bite recognized by symptoms is shown in Figure 13. It was striking that those patients remembered the bite, whose dermatological involvement (ECM and LBC) appeared at the site of it. The tick bite was less frequently observed or remembered in the facial palsy group. This is probably due to the screening characteristics of this manifestation. (Neither the physician nor