STATUS OF SCRUB TYPHUS: A REVIEW

The disease caused by Rickettsiae in human, the most widespread is Scrub typhus. It exists as zoonoses in nature between certain species of trombiculid mites and their small mammals i.e. rats, field mice, shrews. In this humans are the accidental host of the mite-rodent-mite cycle. Scrub typhus has re-emerged in India with ancient outbreaks. It is presently seen in increasing numbers in various south Indian states, north east and of late from north Indian states, and Himalayan foothills –Himachal Pradesh and uttrakhand. The mode of transmission is the bite of infected larval mites and the incubation period is usually 10 to 12 days; varies from 6 to 12 days. Scrub typhus resembles epidemic typhus clinically. The onset is acute with chills and fever is about 104° to 105°F, headache, malaise, prostration and a macular rash appearing around the 5th day of illness, generalized lymphadenopathy and lymphocytosis are common. The main abide in tsutsugamushi disease diagnosis remains in serology. The oldest test is that the Weil-Felix OX K agglutination reaction that is cheap, easy to perform and results are come in one-night. ELISA for the detection of IgM antibodies against Orientia tsutsugamushi offers advantages of being able to test large number of samples at a time and can be automated. Indirect fluorescent antibody assay is the gold standard assay for the serological detection of antibodies in scrub typhus. In children and pregnant women Azithromycin is preferred. Rifampicin is an alternative drug but is not to be given alone to avoid the development of drug resistant.