Evidence of Rickettsia typhi in rat fleas of various habitat and the potential transmission of murine typhus in banjarnegara, Central Java, Indonesia

Murine typhus is a zoonotic infectious disease caused by Rickettsia typhi, whose transmission is carried out by rat fleas. The climatic and ecologic conditions in Banjarnegara is favorable for maintaining reservoirs and vectors of murine typhus. There has been no report about the occurrence of R. typhi in rat fleas. Therefore, we investigated the role of fleas as possible vector of murine typhus in Banjarnegara. During September to Nopember 2017, flea were collected from rats trapping of various habitat in Banjarnegara. Fleas preserved in 70% ethanol were eventually prepared onto slides for identification. Fleas of the same species were pooled by species of small mammal and habitat and then preserved in sodium chloride store at-20°C until evaluated for the presence of Rickettsia typhi by polymerase chain reaction. Two flea species were identified: Xenopsylla cheopis and Stivalius cognatus. Stivalius cognatus was collected from R. exulans and R. tiomanicus. Rickettsia spp. was detected in X. cheopis (45/88) and S. cognatus (3/11). The highest minimum infection rate of R. typhi was seen in X. cheopis infesting R. tanezumi in Kutabanjarnegara village (103.8). The presence of R. typhi in X. cheopis at residential area of Banjarnegara needs serious attention, as a form of awareness of disease transmission, especially murine typhus.