en Infectious Diseases Infectious Diseases Original Article Original Article <span style="font-size:14px;"><span style="font-family:Times New Roman;"><span style="line-height:13.85pt"><b><i><span style="color:blue">Background</span></i></b><i><span style="color:blue">:</span></i> Brucellosis is a common disease between humans and animals that still exists in most parts of Iran. This study investigated the epidemiology of brucellosis in Mazandaran province, Iran, during a nine-year period from the beginning of 2009 until the end of 2017.</span><br> <span style="line-height:13.85pt"><b><i><span style="color:blue">Methods:</span></i></b> This descriptive-analytical study was conducted based on the guidelines of Iran&rsquo;s Ministry of Health and Medical Education on the data of 3732 brucellosis patients. The data were retrieved from the private and public laboratories gathered in a Ministry&rsquo;s database. We used the generalized estimating equation (GEE) for the Poisson regression model (Poisson GEE) to examine the disease incidence based on the studied variables.</span><br> <span style="line-height:13.85pt"><b><i><span style="color:blue">Results:</span></i></b> The age-standardized incidence rate has been 13.2 per 100,000 people (15.6 in men and 21.3 in rural areas). The highest rate (17.2) was in 2012 and the lowest (10.6) was in 2014. The cities of Galugah (35.0) and Qaemshahr and Fereydunkenar (3.0) had the highest and lowest incidence rates. The patients&rsquo; professions had been 30% housewives, 14.9% ranchers, and 14.4% livestock-related professions. The highest standard incidence was in people older than 55 years old. The results of the Poisson GEE regression model showed that the disease incidence has been higher in men compared to women and in rural compared to urban areas (risk ratio = 1.5, 3.4, P = 0.001). </span><br> <span style="line-height:13.85pt"><b><i><span style="color:blue">Conclusion</span></i></b><i><span style="color:blue">:</span></i> Mazandaran faces the risk of increased brucellosis incidence rate. Taking preventive measures, including educating people, are recommended for the near future. </span></span></span><br> &nbsp; Epidemiology, Brucellosis, Poisson Regression, Mazandaran 666 672 http://caspjim.com/browse.php?a_code=A-10-1949-3&slc_lang=en&sid=1 Maryam Salmani Seraji ma.seraji63@gmail.com 100319475328460050007 100319475328460050007 No Department of Biostatistics, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran Jamshid Yazdani Charati jamshid.charati@gmail.com 100319475328460050008 100319475328460050008 Yes Department of Biostatistics, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran Farhang Baba Mahmoudi farhang.baba@yahoo.com 100319475328460050009 100319475328460050009 No Department of Infectious Diseases, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran Reza Ali Mohammadpour Tahamtan mohammadpour2002@yahoo.com 100319475328460050010 100319475328460050010 No Department of Biostatistics, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran Habib Vahedi drhvahedi40@gmail.com 100319475328460050011 100319475328460050011 No Department of Basic sciences, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran Jalil Shojaee jshojaee@yahoo.com 100319475328460050012 100319475328460050012 No Health Sciences Research Center, Faculty of Health, Mazandaran University of Medical Sciences, Sari, Iran