Rickettsial illnesses, a leading cause of acute febrile illness.

Rickettsial illnesses, comprising mainly spotted fever group, typhus group and scrub typhus, are vector-borne re-emerging or newly emerging febrile illnesses where humans are an accidental dead-end host. They are a major cause of non-malarial febrile illnesses among returned travellers. They commonly present as an acute febrile illness and carry a characteristic entry wound (eschar) or a discrete erythematous maculo-popular rash based on the organism and the region. The illness severity is mainly dependent on the virulence of the rickettsial organism and delay in the diagnosis is known to cause severe illness with multi-organ involvement carrying high mortality. Almost all rickettsial infections respond to anti-rickettsial antibiotics such as doxycycline within 48-72 hours. Awareness of rickettsial illnesses and their various clinical presentations helps in early diagnosis and institution of appropriate treatment and hence prevent morbidity and mortality.