[Seroprevalence of Lyme Borreliosis and tick-borne encephalitis in workers at risk, in eastern France]. / Séroprévalence de la borréliose de Lyme et de l'encéphalite à tiques chez des professionnels exposés dans le Grand est de la France.

ABSTRACT

OBJECTIVE: The aim of this article was to assess the seroprevalence of Lyme Borreliosis and tick-borne encephalitis (TBE) among occupationally exposed forest workers. METHODS: Workers exposed to tick bites in Eastern France were interviewed by occupational health physicians of the mutualité sociale agricole (MSA) on their sociodemographic features, their occupational activity, their last tick bite, their clinical history, and their means of prevention. Blood sampling was carried out for antibody detection. RESULTS: Among the 2975 subjects included in the study, the observed seroprevalence was 14.1% for Lyme borreliosis and 3.4% for TBE. Age, occupational activity, and place of residence significantly influenced the serological status of Lyme borreliosis. The seroprevalence was significantly higher among woodcutters (17.5%) than among other occupational categories (p<.001). Seroprevalence in Alsace (26.9%) and Lorraine (16.5%) were significantly higher than in other regions (p<0.001 and p<0.01, respectively). The seroprevalence of TBE was significantly higher in Alsace (5.5%; p<0.001). The rates of seroprevalence for both infections varied according to forest areas. The multifactorial analysis of prevention practices revealed three types of behaviors as far as protection was concerned "rigorous", "partial", or "insufficient". CONCLUSION: These results do not change the present French indications for use of TBE vaccine. They highlight the importance of information on these diseases and the need for further studies on microbial ecology and risk-factors identification.