The ever increasing rate of new cases of Lyme disease, the tendency for chronicity in certain forms of the disease and especially the disputable effect of causal therapy resulted in strenuous efforts to develop an effective vaccine. The authors sum up recent experience with vaccination in the U.S.A. and Europe. Two studies in the U.S. during the years 1994 through 1997 included more than 20 000 probands. In one of the studies, coordinated by Steer (10 936 probands), during the first year twenty-two people of the vaccinated group contracted the disease compared to forty-three people of the non-vaccinated, i.e. placebo group. The vaccine efficacy was 49 percent. During the second year of the study, after the third dose of the vaccine, sixteen vaccinated people contracted the disease vs. sixty-six placebo probands. Vaccine efficacy was 76 percent. Its administration was accompanied by mild to moderate local or systemic reactionlasting up to three days. In the next study, coordinated by Sigal (10 305 probands) the vaccine efficacy was sixty-eight percent in the first year and ninety-two percent in the second, respectively. Both studies proved the vaccine to be safe and efficient in Lyme disease prevention. In comparison with these large long-term double-blind, placebo-controlled studies European research results presented to the medical community for the first time in 1998 in Vienna appear to be of lesser value. Recombinant polyvalent vaccine based on OspC lipoprotein isolated from Borrelia burgdorferi sensu lato was used but only eighty volunteers from Aland Islands participated in the study.

        Key words: Lyme disease, immunisation, recombinant polyvalent vaccine, lipoprotein OspC.