Molecular and serological evidence of flea-associated typhus group and spotted fever group rickettsial infections in Madagascar

• Published in: Parasites & Vectors
• Main Authors: Rakotonanahary, Rado, J L, Harrison, Alan, Maina, Alice, N, Jiang, Ju, Richards, Allen, L, Rajerison, Minoarisoa, Telfer, Sandra
• Other Authors: Unité Peste - Plague Unit Antananarivo, Madagascar, Institut Pasteur de Madagascar, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP), Université d'Antananarivo, Institute of Biological, Environmental and Rural Sciences (IBERS), Biotechnology and Biological Sciences Research Council (BBSRC)-Aberystwyth University, Viral and Rickettsial Diseases Department, U.S. Naval Medical Research, This research was supported by the Wellcome Trust (RCDF and Senior Fellowship to ST, #081705 and #095171), the Institut Pasteur de Madagascar, and the Global Emerging Infections Surveillance and Response System, a Division of the Armed Forces Health Surveillance Center 847705.82000.25GB.A0074
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: Fleas; Madagascar; Murine typhus; Prevalence; Rickettsioses; Rickettsia; Flea-borne spotted fever; MESH: Adult; MESH: Animals; MESH: Rats; MESH: Rickettsia; MESH: Rocky Mountain Spotted Fever; MESH: Rodent Diseases; MESH: Shrews; MESH: Siphonaptera; MESH: Typhus; Epidemic Louse-Borne; MESH: Young Adult; MESH: Antibodies; Bacterial; MESH: Female; MESH: Humans; MESH: Insect Vectors; MESH: Madagascar; MESH: Male; MESH: Middle Aged; MESH: Phylogeny; [SDV.MHEP.MI]Life Sciences [q-bio]/Human health and pathology/Infectious diseases; [SDV.MP.BAC]Life Sciences [q-bio]/Microbiology and Parasitology/Bacteriology; [SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie; Rattus rattus
• Online Access: https://riip.hal.science/pasteur-01652154; https://riip.hal.science/pasteur-01652154/document; https://riip.hal.science/pasteur-01652154/file/molecular_serological%20evidence%20of%20flea-associated%20typhus_Rakotonanaharyetal.pdf; https://doi.org/10.1186/s13071-017-2061-4

International audience Background: Rickettsiae are obligate intracellular bacteria responsible for many febrile syndromes around the world,including in sub-Saharan Africa. Vectors of these pathogens include ticks, lice, mites and fleas. In order to assessexposure to flea-associated Rickettsia species in Madagascar, human and small mammal samples from an urbanand a rural area, and their associated fleas were tested.Results: Anti-typhus group (TGR)- and anti-spotted fever group rickettsiae (SFGR)-specific IgG were detected in24 (39%) and 21 (34%) of 62 human serum samples, respectively, using indirect ELISAs, with six individuals seropositivefor both. Only two (2%) Rattus rattus out of 86 small mammals presented antibodies against TGR. Out of 117fleas collected from small mammals, Rickettsia typhi, a TGR, was detected in 26 Xenopsylla cheopis (24%) collected fromrodents of an urban area (n = 107), while two of these urban X. cheopis (2%) were positive for Rickettsia felis, a SFGR. R.felis DNA was also detected in eight (31%) out of 26 Pulex irritans fleas.Conclusions: The general population in Madagascar are exposed to rickettsiae, and two flea-associated Rickettsiapathogens, R. typhi and R. felis, are present near or in homes. Although our results are from a single district, theydemonstrate that rickettsiae should be considered as potential agents of undifferentiated fever in Madagascar.