Abstract

Scrub typhus is an emerging rickettsial zoonosis which presents with acute febrile illness, but has no specific clinical characteristics and confirmation of diagnosis is possible only in tertiary care centres. A retrospective case - control study was carried out to examine the infection pattern and adequacy of serological diagnosis for scrub typhus in a 132 bedded hospital in North East India. A commercial Immune Chromatographic Test (ICT) which detects total antibodies to Orientia Tsutsugamushi was performed on 123 samples of patients in whom scrub typhus was considered as differential diagnosis. Other tests included Complete Blood Count (CBC), routine urine examination, serum creatinine, liver function tests. Laboratory profile and infection pattern of 67 controls with a negative scrub typhus card test result were compared with a cohort of 56 positive subjects. Statistical analysis was done by Chi-square test and ‘p’ values were calculated. Among the frontline tests, liver function evaluation and proteinuria attained statistical significance. We conclude that ICT for detection of total antibodies against Orientia Tsutsugamushi is useful for a working diagnosis and management of scrub typhus in resource poor settings.