Analysis Of Monitoring Results Of The Severe Fever With Thrombocytopenia Syndrome In A Key Area Of Jiangsu Province

Background:In recent years,some infectious diseases with the main clinical manifestations of fever,gastrointestinal symptoms,platelet and leucocytedecrease have been subsequently found and reported in henan,hubei,shandong,jiangsu,zhejiang and other regions of China.In May 2010,the experts of Chinese Center for Disease Control and Prevention isolated a new virus,which is named severe fever with thrombocytopenia syndrome virus,the disease caused by this virus is named severe fever with thrombocytopenia syndrome.Objective:To investigate the infection of SFTSV among human,animals and arthropods,and to analyze the infection spectrum,epidemiological characters and influence factors of SFTSV infection in a key area of Jiangsu Province(Yixing city),so as to provide evidence for working out prevention and control strategies.Methods:The case was monitored in the city.The Yixing people's hospital was set up as the sentinel hospital.Monitoring areas are set up in Hilly and mountainous areas.According to the geographical environment and the past epidemic situation,the control group was set up in the plain area,and the control study was carried out with the monitoring area,and a certain number of healthy people were selected according to the age group to carry out serological monitoring.Surveillance of animals and insect vectors in some villages and towns in the area of monitoring and control.Cases were investigated with the unified diagnostic criteria.Overall antibodies to SFTS were detected by a novel double antigen sandwich ELISA.Reverse transcription-PCR(RT-PCR)was also used for nucleotide diagnosis.Percentage positive rate was used to describe the positive rate of infection.Chi square test was used to compare the positive rate between the two groups.Results:A total of 39 suspected cases of SFTS were investigated from 2010-2016,and the positive rate of suspected cases was17.95%(7/39).The mortality rate was 42.86%(3/7).The positive rate of the total antibody in general population was 0.12%(2/1668).SFTSV-specific antibodies were found in total number of 451 domestic animals(1.55%)and 370 wild animals(4.59%).Nucleic acid detections were positive with arthropods in 2015 and 2016.11 cases of SFTS cluster epidemic in 1996.The remaining 7 cases were reexamined in 2010,5 cases were positive for SFTSV-specific antibodies.Sampling and testing again in 4 cases of previous outbreaks in 2010,4 cases were positive for SFTSV-specific antibodies.Conclusions:Apparent and latent SFTSV infections tracked back to at least 1996 were preliminarily confirmed in Yixing city and the overall antibody to the virus could last for more than14 years.The virus could be transmitted through blood of acute infection cases among human.The elderly and those who live in hilly areas could be the ricky factors of SFTS.The infection may be a zoonoses with sheep,chickren,mice,rabbit,hedgehog and Shrew as possible host animals.The wild animal positive rate of SFTSV-specific antibodies was higher than that of the livestock animal(?~2=6.63,P=0.01).SFTSV was prevalent in hilly and mountainous areas in Yixing city.