The risk of Borrelia burgdorferi infection and the value
of antibiotic prophylaxis after tick bite
are controversial. In this study, performed in two areas of southwestern
Germany, ticks were
collected from 730 patients and examined by the polymerase chain reaction
(PCR) for
B. burgdorferi. To assess whether transmission of B.
burgdorferi occurred, the patients were
clinically and serologically examined after tick removal and during follow-up
examinations.
Data from all tick bites gave a total transmission rate of 2·6%
(19 patients). Eighty-four ticks
(11·3%) were PCR positive. Transmission occurred to 16
(26·7%) of 60 patients who were
initially seronegative and could be followed up after the bite of
an infected tick. These results
indicate that the transmission rate from infected ticks in Europe is higher
than previously
assumed. Examination of ticks and antibiotic prophylaxis in the case of
positivity appears to
be indicated.