Background: The objective was to compare the clinical features of early local Lyme Disease: Erythema Migrans (EM) between two highly endemic areas: New York State and Northeastern Poland. Study was based on self reporting questionnaires, physical examination, and laboratory results.
Material/methods: Group I (n=27) consisted of citizens from New York State presenting with EM, referred to the study by their physicians. Group II (n=25) consisted of patients treated as outpatients in 1998-1999 at the Department of Infectious Diseases and Neuroinfections, Medical University of Bialystok, Poland. The diagnosis of EM was based on patient history and clinical picture.
Results: Depending on the immune reaction of the host, the clinical picture is variable. The initial symptoms range from discrete to strongly expressed. The inflammatory reaction at the site of tick-bite seems to be milder in Europe than in North America, which is reflected in the prevalence of the annular form of rash and milder expression of general symptoms. Mild or absent general symptoms and the prevalence of the annular over homogenous form are observed in those areas of Europe where Ixodes ricinus is the main vector. In the endemic area of New York State, where Ixodes scapularis mainly occurs, uniform EM with flu-like symptoms is more common.
Conclusions: There are distinct differences in the typical clinical pictures between the two separated endemic areas of New York State and Northeastern Poland, due to different vectors (saliva components?), bacterial genospecies, likely intermediate hosts and climatic differences. Familiarity with the presenting form of the disease can be very important, especially for primary care physicians.