When to Think of Rickettsia.

Rickettsiae are globally encountered pathogens with foci of endemicity and epidemic exacerbations under circumstances of crowding and decline of sanitation. Diagnosis is often missed due to misconceptions about epidemiology, confusing terminology and nonspecific clinical presentation. Rickettsioses should be considered in children with febrile illnesses exceeding the usual duration of a viral infection, in particular in children with rash, lymphadenopathy and nearly normal first-line laboratory tests, who reside in or return from endemic areas, recall a compatible contact history, have a constellation of symptoms starting after an arthropod bite, live under troubled social circumstances, or are part of a cluster of similar cases.