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About The Authors

Albena Toneva
Medical University of Varna
Bulgaria

Department of Hygiene and Epidemiology, Faculty of Public Health

Rositsa Chamova
Medical University of Varna
Bulgaria

Department of Hygiene and Epidemiology, Faculty of Public Health

Miglena Marinova
Medical University of Varna
Bulgaria

Department of Hygiene and Epidemiology, Faculty of Public Health

Lalka Rangelova
National Center for Public Health and Analysis, Sofia
Bulgaria

Rouzha Pancheva
Medical University of Varna
Bulgaria

Department of Hygiene and Epidemiology, Faculty of Public Health

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