Subjective health complaints are not associated with tick bites or antibodies to Borrelia burgdorferi sensu lato in blood donors in western Norway: a cross-sectional study

BACKGROUND There is controversy about chronic health consequences of tick-borne infections, especially Lyme borreliosis. This study aims to assess whether general function, physical fitness and subjective health complaints are associated with tick bites or antibodies to Borrelia burgdorferi sensu lato in blood donors. METHODS Sera from 1,213 blood donors at four different blood banks in Sogn and Fjordane county in western Norway were obtained during January to June 2010, and analysed for specific IgG and IgM antibodies. A questionnaire including questions on tick bites, subjective health complaints, general function and physical fitness was completed. RESULTS Tick bites had been experienced by 65.7% of the study population. 78 (6.4%) were positive for IgG (9.7% in men, 2.4% in women), and 69 (5.7%) for IgM (6.1% in men, 5.1% in women), verified by immunoblot. No association between number of experienced tick bites or seropositivity for Borrelia antibodies and subjective health complaints, reduced general function or reduced physical fitness was found. CONCLUSION The results do not support any association between tick bites or Borrelia antibodies and subjective health complaints in blood donors in an endemic area for Lyme borreliosis.