Fever is one of most common presenting complaints in clinics in tropical countries. Rickettsial infections, enteric fever and leptospirosis are common and important causes of undifferentiated fever in Southeast Asia. Scrub typhus is caused by Orientia tsutsugamushi and humans are typically infected by a bite of an infected chigger (trombiculid mite larva). Clinical diagnosis is unreliable for identifying scrub typhus, unless a tick eschar is present which is almost pathognomonic for the disease in Southeast Asia. A combination of culture, paired serology and PCR has been proposed as the gold-standard method for detection. As a result laboratory confirmation is not widely available and the diagnosis is missed frequently in clinical practice. Some progress has been made in developing such a test and one promising candidate is the Scrub Typhus Detect IgM Rapid Test (InBios International Inc). We plan to use to this test in this study to estimate the prevalence of scrub typhus in selected febrile patients presenting to clinics in Myanmar .