RESUMEN
Since the declaration of a swine flu pandemic by the World Health Organization [WHO], the Islamic Republic of Iran has launched a surveillance system to test all suspected cases, both in community and hospital settings. From June 1[st] to November 11[th], 2009, there were 2662 [1307 females and 1355 males] RT-PCR confirmed cases of pandemic influenza A [H1N1] detected in Iran. Of these cases, 75% were 5-40 years-old. During this period, 58 patients [2.18%] died. Of the total number of cases, 33 were pregnant women with no reported mortalities amongst them. The prevalence of death had no significance correlation with sex and age [P=0.720 and 0.194, respectively]. Geographic distribution of the reported cases showed the highest rates in central and eastern provinces of Iran. There were two disease phases until November 2009, including an initial exogenous wave which blended into a second wave of indigenous disease, with a peak of cases after the start of the educational year. A review of the epidemiology of these initial phases of disease in Iran can help for better planning and more efficient action in future phases of the disease. It is of utmost importance to strengthen the surveillance system for this disease and appropriately transfer the resultant knowledge to the medical professionals, stakeholders and the general population, accordingly