Spatio-Temporal Dynamics Of Epidemics Of Hemorrhagic Fever With Renal Syndrome In Shandong Province

Hemorrhagic fever with renal syndrome (HFRS) is a natural focal disease with severe damages found throughout the world. China is the most HFRS prevalent country in the world, with the number of cases accounting for more than 90% of the world total. HFRS is one of the major infectious diseases which severely affect the people's health in China and listed as one of the key infectious diseases in focus control and prevention in National Outlines for Disease Control and Prevention in the Tenth Five-Year Plan (No. 31 (2002) Wei Ban Ji Kong Fa, MOH). Studies show that Hantaviruses(HV) are the main strains prevalent in China with at least Hantaan(HTN) and Seoul(SEO) types. At present, although the types of HFRS focus and their characteristics of spatio-temporal distribution have been basically understood, yet the HFRS incidence and spatio-temporal dynamic characteristics of continuous changes have not been expounded. Thus, the previous prevention measures including vaccine immunization and deratization have not been adjusted according to the characteristics of spatio-temporal changes, with HFRS epidemics still serious, the scope of old endemic areas continuously expanded, new endemic areas emerging, and epidemics out of control. Therefore, the study on spatio-temporal dynamics of HFRS epidemics not only has a great theoretical significance for fully understanding the epidemiological law of HFRS, but also has a great realistic significance for working out practical prevention and control measures suited to the time and local conditions.Shandong Province, always ranked No. 1 in the HFRS incidence, accounting for around 1/3 of the total, with Hantaviruses(HV) particularly Hantaan(HTN) and Seoul(SEO) types as the main strains, is the most HFRS prevalent region in China. Since the early 1980's, the types of endemic area began to evolve, in the middle of 1990's, evolved from the simple type I or type II to the type I and type II mixed type. At present, the structure of endemic areas is still in dynamic change. Since HFRS is most prevalent in Shandong, with the number of cases accounting for 1/3 of the national total, and in elevation and latitude, Shandong Province is in the transitional area between the stable type II endemic area in low latitudes within the third step and type II endemic area in high latitudes, and completely experienced the process of evolution from the Apodemus type focus to the Apodemus dominant mixed type focus and then to the Rattus dominant mixed type focus. Therefore, Shandong is the most typical and representative endemic area for the study on spatio-temporal dynamics of HFRS epidemics. For this reason, this study intends to utilize the data on the annual HFRS incidence by county in Shandong from 1974 to 2004 (the annual average...