Ramyasree A, Kalawat U, Rani N D, Chaudhury A
Department of Microbiology , Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, India.
Indian J Med Microbiol. 2015 Jan-Mar;33(1):68-72. doi: 10.4103/0255-0857.148381.
Scrub typhus is a rickettsial infection which is caused by Orientia tsutsugamushi and transmitted by the bite of the chigger of a mite. Delay in diagnosis can be fatal otherwise the treatment is simple, doxycycline being the drug of choice. Indirect immunoflurescence is considered gold standard but it is not used in India as it is costly and also not available. There is need for rapid, economic and simple test for the diagnosis of scrub typhus. This study was taken up to study the seroprevalence of scrub typhus in Andhra Pradesh and to compare two commonly used serological methods; rapid test and IgM ELISA.
This is a prospective study in which 100 serum samples from clinically suspected cases collected over a period of 3 months were processed for the detection of IgM antibodies for scrub typhus by ELISA and Rapid test. Samples were also tested for leptospirosis and dengue fever which the other common causes of fever prevalent in this region.
Total number of samples processed was 100 of which 52 were males and 48 females. Among the hundred samples 39 were seropositive. Positivity was higher in the age group of patients between 16 and 30 yrs of age. There was 97% correlation between ELISA and rapid method. Of the 100 samples only three samples positive by ELISA were negative by rapid method. Fever was the most common manifestation and there was no eschar and no mortality reported.
Scrub typhus should be included in the differential diagnosis of fever of unknown origin along with dengue, malaria and leptospirosis which are the other common endemic infections in this part of the country.
恙虫病是由恙虫病东方体引起的立克次体感染，通过恙螨幼虫叮咬传播。诊断延误可能致命，否则治疗简单，多西环素是首选药物。间接免疫荧光法被认为是金标准，但在印度未被使用，因为其成本高且无法获得。需要一种快速、经济且简单的恙虫病诊断检测方法。本研究旨在研究安得拉邦恙虫病的血清流行率，并比较两种常用的血清学方法；快速检测法和 IgM ELISA。
这是一项前瞻性研究，对在 3 个月内收集的 100 份临床疑似病例的血清样本进行处理，通过 ELISA 和快速检测法检测恙虫病 IgM 抗体。样本还检测了钩端螺旋体病和登革热，这是该地区其他常见的发热原因。
共处理样本 100 份，其中男性 52 份，女性 48 份。在这 100 份样本中，39 份血清呈阳性。16 至 30 岁年龄组患者的阳性率更高。ELISA 和快速检测法之间的相关性为 97%。在 100 份样本中，仅 3 份 ELISA 阳性样本快速检测法呈阴性。发热是最常见的表现，未报告焦痂和死亡病例。
恙虫病应纳入不明原因发热的鉴别诊断，与登革热、疟疾和钩端螺旋体病一起，这些是该国该地区其他常见的地方感染。
