title: Epidemiologic studies of leptospiroses in the Plovdiv region of Bulgaria.
abstract: BACKGROUND
  The natural habitat of leptospira along the Maritsa river, the high level of development of the land-cultivation and cattle-raising underscore the importance of establishing the exact prevalence of leptospiroses ranking it among the highest in the country. The changes occurring in the economy and land-making of the country following 1990 are reflected in the prevalence of leptospiroses during this period.
  
  
  METHODS
  We studied 95 patients of the Infectious Disease Clinic of the Higher Medical Institute of Plovdiv with serological evidence for leptospirosis for the period 1987-1998. The patients were analyzed based on the following criteria: morbidity, age, gender, season, etiologic structure, mechanism and factors for the transmission of disease etc.
  
  
  RESULTS
  The morbidity rate of Leptospira has shown a clear tendency towards increase since 1992. In terms of etiology L. pomona ranked first accounting for 44.22% of the cases as compared with the prevalence of L. tsalapitsa--22.10%. The isolation rates of those who had been infected during contact with animals (swine predominantly) was 40.44%, during plant watering--38.95%, and 17.89% resulted from bathing in the Maritsa river or its tributaries. Patients in the high-risk groups were characteristically 20-39 years old, cattle-raisers, fishermen, land workers. The highest number of registered cases occurred in July through August.
  
  
  CONCLUSIONS
  Based on these results from the epidemiologic study effective measures aimed at the reservoir, mechanism of transmission of the infection and the risk groups can be implemented so that the epidemiologic and epizootic control of leptospiroses can be improved.
authors.affiliation: Department of Infectious Diseases, Epidemiology and Parasitology, Higher Medical Institute, Plovdiv, Bulgaria.
authors.forename: Y
authors.initials: Y
authors.lastname: Stoilova
authors.forename: N
authors.initials: N
authors.lastname: Popivanova
mesh_terms: D000293:Adolescent; D000328:Adult; D002031:Bulgaria; D002648:Child; D005260:Female; D006801:Humans; D007922:Leptospirosis / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D015995:Prevalence