三峡库区兴山县钩端螺旋体宿主动物带菌状况及人群免疫水平分析

Status of Leptospira of host animals and serum immunity level of population in Xingshan County, Three Gorges region

目的掌握兴山县钩端螺旋体病(钩体病)宿主动物带菌及人群免疫水平,为进一步做好钩体病的预防与控制提供依据。方法按照《全国钩端螺旋体病监测方案》开展鼠、家畜、青蛙等宿主动物带菌调查及健康人群血清学监测。结果平均鼠密度为1.80%。鼠种构成以黄胸鼠、小家鼠和黑线姬鼠为优势种,平均带菌率为3.75%。共检测病人尿液及家畜、青蛙、稻田疫水等7类样本565份,培养阳性菌株4株,阳性率为0.71%,其中稻田疫水2株,病人尿液、蛙肾各1株,菌株经鉴定黄疸出血群1株,秋季热群3株。人群钩体抗体阳性率平均为28.62%,青壮年阳性率较高,以黄疸出血型、七日热型、流感伤寒型、波摩那型为主。在监测中发现1例在农贸市场感染的经济型钩体病。结论兴山县钩体宿主动物带菌率低,血清学显示人群钩体隐性感染率较低,在山区型钩体自然疫源地存在的情况下,其发病率与社会因素和自然因素密切相关。农贸市场、畜牧养殖区及其周边为经济型钩体病疫源地,病例分析已经得到证实,建议今后应将其纳入预防和监测范围。

Objective To understand the status of host animals infected with Leptospira and the serum immunity level of the crowd in Xingshan County, so as to provide the evidence for formulating the interventions for further controlling and preventing leptospirosis. Methods In accordance with the ＂National Leptospirosis Surveillance Program＂, a carrier survey of rat, cattle, frogs and other host animal was carried out, and a serological monitoring of healthy population was performed.Results The average rodent density was 1.80%. Rattus flavipectus, Mus musculus and Apodemus agrarius were the dominant species with the average carrier rate of 3.75%. A total of 565 samples of 7 kinds of the patient urine, livestock, frogs and paddy field water were checked, and 4 positive strains were cultured with the positive rate of 0.71%. The paddy water had 2 positive strains, patient urine had 1 positive strain, and frog kidney had 1 positive strain. The positive strains were identified as L.icterohemorrhagie（1 strains）, and L. autumnalis（3 strains）. The average antibody positive rate of leptospirosis of the population was 28.62%, and the positive rate of the young was higher. In leptospirosis serogroup, L. icterohemorrhagie, L. hebdomadis, L.grippotyphosa and L. pomona were dominant strains. One case was found as the economic type of leptospirosis and he was infected at a farmer＇s market. Conclusions The Leptospira carrier rate of host animals is low in Xingshan County. The seroepidemiological monitoring results show the recessive infection rate of Leptospira in population is also low. The natural foci exist in the mountains and the prevalence of leptospirosis is closely related to the social and natural factors. The farmer＇s market, livestock culture zones and their surrounding are the epidemic foci of the economic type of leptospirosis, and therefore,they should be included in the scope of prevention and monitoring in the future.