Rickettsial Infections of Fleas Collected From Small Mammals on Four Islands in Indonesia

Abstract

Ectoparasites were sampled from small mammals collected in West Java, West Sumatra, North Sulawesi, and East Kalimantan, Indonesia, in 2007-2008 and were screened for evidence of infection from bacteria in the Rickettsaceae family. During eight trap nights at eight sites, 208 fleas were collected from 96 of 507 small mammals trapped from four orders (379 Rodentia; 123 Soricomorpha; two Carnivora; three Scandentia). Two species of fleas were collected: Xenopsylla cheopis (n = 204) and Nosopsyllus spp. (n = 4). Among the 208 fleas collected, 171 X. cheopis were removed from rats (Rattus spp.) and 33 X. cheopis from shrews (Suncus murinus). X. cheopis were pooled and tested for DNA from rickettsial agents Rickettsia typhi, Rickettsia felis, and spotted fever group rickettsiae. R. typhi, the agent of murine typhus, was detected in X. cheopis collected from small mammals in West Java and East Kalimantan. R. felis was detected in X. cheopis collected from small mammals in Manado, North Sulawesi. R. felis and spotted fever group rickettsiae were detected in a pool of X. cheopis collected from an animal in East Kalimantan. Sixteen percent of the X. cheopis pools were found positive for Rickettsia spp.; four (10.8%) R. typhi, one (2.7%) R. felis, and one (2.7%) codetection of R. felis and a spotted fever group rickettsia. These data suggest that rickettsial infections remain a threat to human health across Indonesia.

Bartonella and Rickettsia in arthropods from the Lao PDR and from Borneo, Malaysia

“…Recently, R. felis has been detected in East Kalimantan (Indonesian Borneo) in pools of Xenopsylla cheopis collected from the shrew, Suncus murinus and the rat Rattus norvegicus [3]. These findings suggest that flea-borne spotted fever is likely to be a human disease in these areas and urges that R. felis should be included in the differential diagnosis of fever.…”

“…In addition, Bartonella clarridgeiae and Rickettsia felis were detected in fleas collected in Phu Khao Khoay, near Vientiane [30]. A clinical case of murine typhus ( R. typhi ) was reported in a traveller from Brunei [9] and R. felis and R. typhi have been detected from flea species associated with small mammals in these area [3]. A recent study on flea-host associations, for example, compiled no more than 15 fleas species described to date to occur on small terrestrial mammals on Borneo Island, highlighting the lack of our understanding of the species diversity of possible vector and their role in transmitting diseases [32].…”

High Prevalence of Rickettsia typhi and Bartonella Species in Rats and Fleas, Kisangani, Democratic Republic of the Congo

“…The prevalence of R. typhi in fleas and rodents DRC is one of the highest from the world. In the last years, R. typhi was identified in 10.8% of X. cheopis pools (4 of 16) in Indonesia, 33 in tissues from three rats and in 10% of fleas from each animal in California, 34 in 4% X. cheopis and 6.6% in Leptopsylla segnis in Cyprus, 35 and in 3.2% flea pools in Korea. 36 The flea remains infected with R. typhi for life with good fitness and the horizontal and vertical transmission increase the infected populations in this endemic area.…”

Rickettsial Infections in Southeast Asia: Implications for Local Populace and Febrile Returned Travelers

“…32,33 Infection of rat flea Xenopsylla cheopis with R. felis has also been found in Indonesia, which increases the possibility of human infections with R. felis in the region, although no clinical case has been reported to date. 35,37 Ectoparasite field surveys of villages in Laos and Malaysian Borneo of domestic animals also showed significantly high overall R. felis DNA detection rates of 76.6% and 74.4%, respectively. 36 However, in contrast, another study in peninsula Malaysia showed a lower rate (2.9%) of R. felis DNA detection.…”

“…[26][27][28][29] Socioeconomically, agricultural, plantation, or forest workers in Thailand, Malaysia, and Indonesia were frequently affected by scrub typhus and SFGR infections. 21 [32][33][34][35][36][37][38] Rodents were found to be important reservoirs for SFGR and murine typhus; high seropositive rates (up to 39.1% for SFGR) were observed in some parts of rural Indonesia. 32,33 Infection of rat flea Xenopsylla cheopis with R. felis has also been found in Indonesia, which increases the possibility of human infections with R. felis in the region, although no clinical case has been reported to date.…”