FIELD SURVEY ON TSUTSUGAMUSHI DISEASE IN TAIWAN IN CONNECTION WITH THE INCREASE OF TSUTSUGAMUSHI DISEASE CASES IN RECENT JAPAN

1986年7月24日至8月17日在台湾进行了一次恙虫病流行病学现场调查。1987年将收集到的资料带回日本进行分析。从统计资料得知，台湾每年约有100例恙虫病病例。病人多为澎湖群岛的农民和军人。（澎湖群岛）经现场调查，也证实病人是在居住地周围的灌木丛和耕地中感染的，用间接荧光抗体试验和免疫过氧化物酶试验检测了40份病人血清对Gilliam、Karp和Kato原型菌株的反应性，结果表明，该血清与Gilliam和Karp株反应强烈。在免疫印迹试验中，这些患者的血清与所有原型的45- 65 K多肽都有明确的反应，认为这些多肽是菌株特异性抗原。在澎湖列岛、台东、屏东等地采集58只哺乳动物，包括臭鼩 31只、小家鼠8只、黄毛鼠4只、板齿鼠15只，共采集恙螨7，395只。纤恙螨（Leptotrombidium L.）各调查区螨类中，以德氏螨为优势种，占90%以上。未发现纤恙螨亚属的其它种，提示纤恙螨属是我国的一个亚属。（L.）deliense是这些地区恙虫病的主要媒介。从6种啮齿动物中分离到立克次体，其多肽组成和抗原成分正在详细研究中。

An epidemiological field research on tsutsugamushi disease in Taiwan was carried out during the period from 24 July to 17 August, 1986. The data and materials collected were brought back to Japan and analysed in 1987.From the statistical data, it was known that about 100 cases of tsutsugamushi disease were recorded yearly in Taiwan. Most of the patients were farmers and military soldiers on Peng-hu Isls. (Pescador Isls.) and in Tai-tung Prefecture, and most of the cases occurred in summer, By the field surveys, it was also demonstrated that the patients had acquired the infection in bushes aroud their residing sites and cultivated fields.The reactiveities of 40 patients' sera collected in the present survey to the prototype strains of Gilliam, Karp and Kato were examined by the indirect fluorescent antibody test and the immunoperoxidase test, and it was shown that the sera reacted strongly with Gilliam and Karp strains. In immunoblotting assay, these patients' sera reacted clearly with 45-65K polypeptides of all prototypes which were considered to be a strain specific antigen. The relatively low specificity in the reactivities to the prototype strains suggests that the rickettsiae in Taiwan might have antigenic properties distinctive from the prototypes.A total of 58 mammals comprising of 31 Suncus murinus, 8 Mus muculus, 4 Rattus losea and 15 Bandicota indica were trapped on Peng-hu Isls, and in Tai-tung and Ping-tung Prefectures, and 7,395 trombiculid mites were collected from them. Leptotrombidium (L.) deliense was the predominant species occupying more than 90% of mites popolations collected in every area surveyed. No other species of the subgenus Leptotrombidium was detected suggesting that L.(L.) deliense is the main vector of tsutsugamushi disease in these areas. Rickttiae were isolated from 6 rodents, and their polypeptide composition and antigenic components are now being examined in detail.