山东地区秋冬型恙虫病传播媒介的调查研究

INVESTIGATION ON THE VECTORS OF SCRUB TYPHUS IN THE FOCI OF SHANDONG PROVINCE.

目的 :探讨山东地区恙虫病传播媒介。方法 :1 995年 5月～ 2 0 0 2年 4月在山东恙虫病疫区捕鼠。观察鼠体外恙螨季节消长 ,分离恙虫病东方体 (Ot)。结果 :室内外共捕捉到的 5 2 7只活鼠 (黑线姬鼠 335只 ,大仓鼠 1 1 9只 ,黑线仓鼠 6只 ,小麝鼠句 2只 ,褐家鼠 6 3只 ,小家鼠 2只 ) ,从活鼠体外共检获 1 5 4 6 7只恙螨 ,其中太平洋无前恙螨最多 5 72 0只 ,其它螨数量依次为小盾纤恙螨 4 1 75只 ,临淮岗纤恙螨 30 90只 ,须纤恙螨 1 6 87只 ,泰山纤恙螨 4 6 6只 ,脆弱无前恙螨 32 9只。恙螨季节变化 :小盾纤恙螨主要出现在 9～ 1 2月 ,高峰在 1 1月 ,是秋季鼠体外绝对优势种 ;须纤恙螨出现在 1 0～翌年 4月 ,高峰在 1 2月 ,为冬季优势螨种 ,临淮岗纤恙螨 5月出现 ,1 1月消失 ,高峰在 8月 ,为夏季优势种 ;泰山纤恙螨主要出现在6～ 1 0月 ,数量较少 ,且起伏较大 ;太平洋无前恙螨、脆弱无前恙螨全部采自仓鼠 ,主要出现在 4～ 1 2月 ,高峰期在 7月。Ot分离 :小盾纤恙螨共接种 1 1批 ,分离到 5株 Ot;须纤恙螨、临淮岗纤恙螨和太平洋无前恙螨分别接种 4批 ,分离到 4株、 2株和 2株 Ot。小盾纤恙螨是恙虫病发病季节疫区鼠体外优势螨种 ,季节消长与当地人群恙虫病季节分布基本一致 ;能自然感染。

Objective:In order to investigate the vectore of scrub typhus in Shandong province.Methods:Rodents were captured from May 1995 to April 2002,Observation of fluctuation of chigger mites and isolation of Orientia tsutsugamushi(Ot) therefrom were carried out.Results:A total of 15467 chigger mites,consisting of 6 species from two genera,were collected from 527 rodents(including 335 Apodemus(A.) agrarius,119 Cricetulus(C.) triton,6 C.barabensis,63 Rattus(R.) norvegicus,2 Crocidura(C.) suaveolens,2 Mus(M.) musculus) captured in Fei county,Jinan,Junan and zouping.Walchia(W.) pacifica was the most predominant in number,followed by leptotrombidium(L.) scutellare,L.linhuaikongense,L.palpale,L.taishanium,and W.fragilis.L.scutellare was present from September to December(the epidemic season of scrub typhus in Shandong) with a remarkable peak in November,whereas L.palpale occurred from October to April(the second year) with peak in December.L.linhuaikongense was found from May to November,with peak in August.W.pacifica appeared from April to December with peak in July.Ot was isolated from L.scutellare,L.palpale,L.linhuaikongense and W.pacifica.The main serotypes of Ot isolated from the chigger mites were of the Gilliam type,but Karp type also existed in L.linhuaikongense.Conclusion:L.scutellare is the most important vector whice caused the endemic of this disease in Shangdong province,and L.palpale,L.linhuaikongense and W.pacifica may serve as the vectors in this and L.palpale,L.linhuaikongense and W.pacifica may serve as the vestors in this area.