Epidemiological Analyis Of Epidemic Hemorrhagic Fever In YiTong County Between 1999 And 2004

Hemorrhagic fever with renal syndrome (alias epidemic hemorrhagic fever) is one kind of disease of natural focus caused by Hantaanvirus, and it is a category â…¡communicable disease prescribed in << Law on the Prevention and Control of Infectious Disease of the People's Republic of China>>. Murid is the natural host and the principal infection source. According to the different types of infection sources of hemorrhagic fevers, the disease can be classified as two chief types, their prevalence are caused by Apodemus agrarius and rattus. and apodemus agrarius is the principal host and infective agent of type apodemus agrarius, brown rattus andersoni is for type rattus. There are three sorts of epidemic areas of infectious disease in our country, they are type apodemus agrarius, type rattus and their mixed type. And we have also found that there is a kind of Puumala virus called. More than 30 countries around the world have hemorrhagic fever with renal syndrome patients, most of them belong to European and Asian countries and among those, China is one of those countries which has the highest incidence. Over 90 percent of the patients in the world who are infected by Hantaan virus are from China. And China is the country which is severest damaged by Hantaan virus. Once there were over 110,000 patients in one year, and the number of patients is around 25,000 in recent 10 years. The worse thing is that there are some new areas falling into the epidemic areas of infectious disease, and sometime, the disease breakout and prevail in those areas, also, the type of the disease can be different from the old ones in those old epidemic areas of infectious disease. Most cases are adolescents and postadolescents. The disease not only does damages to our health and life security, but also the development of our country's economy. So it is an important problem of public health. The first case in JiLin was reported in 1955, and after that, the incidence fluctuated from 0.07/100,000 to 7.82/100,000, and 5.45 percent to 47.83 percent for the case fatality rate. Soul type hemorrhagic fever was first reported in JiLin in 1998, and in the following days, the epidemic areas of infectious disease spreader around from ShuangYang district, YiTong county, PanShi city. In 1999, the cases infected by experimental animals were reported in ChangChun and YanBian. Siping, located in the south of JiLin, is one of the principal agriculture sections in JiLin province. YiTong county, located in the east mountain area and halfway mountain area, is the main epidemic area of infectious disease in Siping. There were sporadic cases ever since 1950 to the late of 1980s. And among those cases, most of them are peasants, forestry workers and open country workers who lived in the mountain area and halfway mountain area. Apodemus agrarius (vole) is the main host and infection sources. With the extending of the epidemic areas of infectious disease and the type of disease transferring from type apodemus agrarius to soul type or the mixed type, the disease spreading from countryside to town, the increasing extent of the pestilence is high in these two years. There were 416 cases were reported from 1999 to 2004 in SiPing, and they distributed to each county( city, district). YiTong had the most cases, and its 273 cases accounted for 65.63 percent of the total number. There were cases reported every month in the whole year. And it's been shown that there were two peaks in each year, the first one was from March to June, the second one was from November to the next January. The principal part of cases were peasants, they accounted for 80.29 percent. The average age of the cases were from 20 to 49. And in those cases, the ratio of male and female was 4.94.YiTong county was chosen as the surveillance spot in this study because it was a severe county in JiLin province. Through the epidemiology and etiology surveillance of hemorrhagic fever, we analyzed the development and the regular pattern of epidemic hemorrhagic fever in YiTong from 1999 to 2004, and we also studied its host, the distribution of etiological agents and the factors that favored its prevalence. All these can provide some theory basis for preventing and controlling the disease in YiTong. This study focused on analyzing and describing the distribution characteristic of time, sides, population and the influential factors of epidemic hemorrhagic fever from 1999 to 2004 in YiTong through analyzing the pestilence surveillance data. We can get the type of epidemic area of infectious disease and the condition of natural infection in population through analyzing its host and the surveillance data of serology. It has been shown that the incidence has a rising tendency, and the epidemic areas are spreading. We can see bimodal pattern in the distribution table changed with time. And in the cases, those peasants who are adolescents and postadolescents are the major part, and male patients are more than female patients. YiTong county is a mixed type area by analyzing its host data, although soul type is primary. It is suggested that we pay more attention to do the work of deracination and vaccinate larger scale of population. We should strengthen the work of shriveling the host and human serology, and at the same time manage scientifically in order to prevent the pestilence from arising.