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Research Articles






Lata R Chandel, Subhash Chand Jaryal, Vijay Singh Chandel, Joginder Thakur, Deshraj Sharma,Tara Chand Mahant



ABSTRACT: Background: Scrub typhus is a tropical febrile zoonotic disease caused by Orientia tsutsugamushi of the rickettsial family. Clinical diagnosis of scrub typhus is often difficult because of similarity of symptoms to other febrile illnesses such as dengue, leptospirosis, malaria and other viral hemorrhagic fevers. Accuracy and rapidity of a diagnostic test to Orientia tsutsugamushi is an important step to diagnose this disease. Method: The present study was performed to compare the results of recently introduced IgM ELISA, considered to be a reference standard and rapid card test Bioline SD tsutsugamushi on 232 non-repeated serum serum samples of patients, suspected to be suffering from Scrub Typhus. Results: Out of 232 patients, 32 (13.8%) patients were found to be serologically positive for Scrub Typhus by IgM ELISA and 30 (12.9%) showed positive results by rapid card test Bioline SD tsutsugamushi. Maximum patients (75%) were between the age from 20-50 years. Majority i.e 17 (53.1%) of patients were females. Sensitivity and Specificity of Rapid card test in relation to IgM ELISA was found to be 93.75% and 100% respectively. Positive Predictive Value of Rapid Card test was found to be 100% and Negative Predictive Value was found to be 99.04%.  Conclusion: The rapid Scrub Typhus IgM kit can be used as a Point-of-Care (PoC) test as it showed good sensitivity and specificity. The kit would be helpful in both urban and remote rural parts of Himachal Pradesh for the rapid diagnosis of Scrub typhus.

KEY WORDS: Scrub typhus, Rapid Card Test, IgM ELISA



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