en Original article Original article <p><strong>Introduction </strong><strong>: </strong>This study was aimed to investigate the effects of risk factors, and environmental and climatic factors a ffecting the occurrence <strong></strong>of <strong></strong>Crimean-Congo <strong></strong>hemorrhagic fever (CCHF) in <strong></strong>Iran. We used <strong></strong>temporal modeling <strong></strong>to <strong></strong>predict the future <strong></strong>occurrence <strong></strong>of the disease in the country . <strong>Methods </strong><strong>: </strong>We analyzed the data <strong></strong>of 165 <strong></strong>CCHF <strong></strong>patients from all over <strong></strong>Iran (e xcept the districts Zabol <strong></strong>and <strong></strong>Zahedan in Eastern Iran ) during 2000 to 2006. In this study, 130 districts with at least one <strong></strong>reported case patient, and 780 districts with no reported case patient, as the control group, were included in <strong></strong>the <strong></strong>model. Logistic regression was used to <strong></strong>design the temporal <strong></strong>model of <strong></strong>the <strong></strong>disease <strong></strong>at the <strong></strong>district-month level nationwide with the purpose <strong></strong>of predicting <strong></strong>the occurrence <strong></strong>of <strong></strong>CCHF <strong></strong>disease with in <strong></strong>one month in a district. <strong>Results: </strong>The designed model indicated that the history of previous reports of the disease in a <strong></strong>district <strong></strong>increased the risk of further reports of the disease (odds ratio: 2.53 (95% CI: 1.61, 3.97), (P ‌ <0.001)). Moreover, w ith each one-million increase in <strong></strong>the <strong></strong>urban population, the odds of a report of the disease increased 20% (P ‌ =0.003). The odds of the occurrence of the disease were reduced by 9% w ith the increase in e ach degree of latitude (P ‌ =0.028). The odds of the occurrence of the disease increased 6.25 times w ith the increase in e ach kilometer of altitude (P ‌ <0.001). T he disease had a decreasing s ecular trend so that the occurrence of the disease was reduced by 10 ‌ % each year (P ‌ =0.008). <strong>Conclusion </strong><strong>: </strong>Our findings showed that based on the history of CCHF in districts, and population and geographical features, hot zones may be defined with some acceptable accuracy. <i>J Med Microbiol Infec Dis, 2014, 1 (2): 7 pages. </i></p> Hemorrhagic Fever Virus Crimean-Congo, Iran, Temporal Modeling 28 34 http://jommid.pasteur.ac.ir/browse.php?a_code=A-10-32-2&slc_lang=en&sid=1 Ehsan Mostafavi No Department of Epidemiology, Pasteur Institute of Iran, Tehran, Iran Ali Akbar Haghdoost Yes Research Center for Modeling in Health, Institute of Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran Amin Doosti Irani No Department of Epidemiology & Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Saeid Bokaei No Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran Sadegh Chinikar No Arboviruses and Viral Hemorrhagic Fever Laboratory, National Reference Laboratory, Pasteur Institute of Iran, Tehran, Iran