Abstract:

Objective To investigate the host animals and vectors of severe fever with thrombocytopenia syndrome virus (SFTSV) and to provide a scientific basis for the prevention of this infectious disease in Donghai county, Jiangsu province, China. Methods Rodents were captured by squirrel-cage method in the field and in the residential areas of the disease epidemic foci; the capture rate of rodents was calculated, and the captured rodents were identified; the heart, liver, spleen, lung, kidney and brain of each rodent were collected. The blood of local cattle, sheep, pigs, chickens and dogs were aseptically collected. Arthropods, such as mites, ticks and mosquitoes, on the cattle, sheep, pigs, chickens and dogs were collected. The SFTSV nucleic acid in the viscera of rodents and in the mites, ticks, and mosquitoes were quantified by fluorescence quantitative RT-PCR. Total antibodies to SFTSV in the sera of animals were detected by double-antigen sandwich ELISA. Results There were six major species of rodents in Donghai county, Jiangsu province, China, i.e., Apodemus agrarius, Large hamsters, Little hamsters, Crocidura lasiura, Rattus norvegicus and Mus musculus. The capture rate of wild rodents was relatively high (13.47%), with A. agrarius as the major species, while the capture rate of house rodents was relatively low (6.98%), with M. musculus and R. norvegicus as the major species. All rodents were infected with SFTSV to different extents. Among wild rodents, the SFTSV infection rate was the highest in the liver (31.57%, 6/19), followed by the heart and lung (21.05%, 4/19), the kidney, spleen, and brain (10.53%, 2/19). Among house rodents, SFTSV nucleic acid was detected only in the heart and brain, and there was a single organ affected in any infected individual. The total SFTSV infection rates in cattle and chickens were 4.55% and 1.54%, respectively. Among arthropods, Leptotrombidium scutellare and Laelaps echidninus also carried SFTSV, but SFTSV nucleic acid was not detected in ticks and mosquitoes. Conclusion Rodents, cattle, chickens, L. scutellare, and L. echidninus may be the host animals or vectors of SFTSV in Donghai county.

Key words: Severe fever with thrombocytopenia syndrome virus, Host animal, Surveillance, Infection rate

摘要：

目的 调查了解发热伴血小板减少综合征病毒(Severe fever with thrombocytopenia syndrome virus,SFTSV)的宿主动物和传染源在动物及媒介中的分布情况,为该传染病的防治工作提供科学依据。方法 采用鼠笼法在发病区野外及居民区捕鼠,计算捕获率并进行鼠种分类,取其心、肝、脾、肺、肾、脑脏器;无菌采集当地的牛、羊、猪、鸡、犬等动物血,并采集螨、蜱、蚊等节肢动物;采用荧光定量RT-PCR检测鼠体脏器及螨、蜱、蚊体内SFTSV核酸;采用双抗原夹心ELISA法检测动物血清中SFTSV总抗体。结果 东海县鼠类主要有黑线姬鼠、大仓鼠、小仓鼠、臭鼩鼱、褐家鼠、小家鼠6种;野鼠捕获率较高为13.47%,主要鼠种为黑线姬鼠;家鼠捕获率相对较低为6.98%,主要鼠种为小家鼠、褐家鼠;各种鼠均有不同程度感染SFTSV,野鼠的心、肝、脾、肺、肾、脑脏器感染SFTSV构成比肝脏最高为26.32%(5/19)>心、肺的21.05%(4/19)>肾、脾、脑的10.53%(2/19);室内鼠仅有心、脑脏器检出SFTSV核酸阳性,且为单一脏器感染;牛、鸡SFTSV的总感染率分别为4.55%和1.54%;节肢动物中的小盾纤恙螨及毒棘厉螨也携带SFTSV,而蜱和蚊未检出SFTSV核酸。结论 鼠类、牛、鸡及节肢动物中的小盾纤恙螨及毒棘厉螨可能是该地SFTSV的宿主动物或传播媒介。

关键词: 发热伴血小板减少综合征病毒, 宿主动物, 监测, 带病毒率