Rickettsia felis identified in two fatal cases of acute meningoencephalitis

BACKGROUND: Rickettsia felis has recently emerged worldwide as a cause of human illness. Typically causing mild, undifferentiated fever, it has been implicated in several cases of non-fatal neurological disease in Mexico and Sweden. Its distribution and pathogenicity in Southeast Asia is poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: We retroactively tested cerebrospinal fluid (CSF) or sera from 64 adult patients admitted to hospital in North Sulawesi, Indonesia with acute neurological disease. Rickettsia felis DNA was identified in the CSF of two fatal cases of meningoencephalitis using multi-locus sequence typing semi-nested PCR followed by Sanger sequencing. DNA from both cases had 100% sequence homologies to the R. felis reference strain URRWXCal2 for the 17-kDa and ompB genes, and 99.91% to gltA. CONCLUSION/SIGNIFICANCE: The identification of R. felis in the CSF of two fatal cases of meningoencephalitis in Indonesia suggests the distribution and pathogenicity of this emerging vector-borne bacteria might be greater than generally recognized. Typically Rickettsia are susceptible to the tetracyclines and greater knowledge of R. felis endemicity in Indonesia should lead to better management of some acute neurological cases.