Susceptibility to Yersinia pestis experimental infection in wild Rattus rattus, reservoir of plague in Madagascar.

• Published in: EcoHealth
• Main Authors: Tollenaere, C., Rahalison, L., Ranjalahy, M., Duplantier, J.-M., Rahelinirina, S., Telfer, S., Brouat, C.
• Other Authors: Centre de Biologie pour la Gestion des Populations (UMR CBGP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université de Montpellier (UM)-Institut de Recherche pour le Développement (IRD France-Sud )-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Unité Peste - Plague Unit Antananarivo, Madagascar, Institut Pasteur de Madagascar, Réseau International des Instituts Pasteur (RIIP)-Réseau International des Instituts Pasteur (RIIP), Institute of Environmental and Biological Sciences, University of Aberdeen
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2010
• Subjects: Yersinia pestis; rodent-borne disease; pathogen-mediated selection; Madagascar; Experimental challenge; infectious disease resistance; MESH: Animals; MESH: Antibodies; Bacterial; MESH: Sex Factors; MESH: Survival Analysis; MESH: Yersinia pestis; MESH: Disease Models; Animal; MESH: Disease Reservoirs; MESH: Enzyme-Linked Immunosorbent Assay; MESH: Female; MESH: Madagascar; MESH: Male; MESH: Plague; MESH: Rats; [SDV]Life Sciences [q-bio]; Rattus rattus
• Online Access: https://hal-riip.archives-ouvertes.fr/pasteur-00836576; https://doi.org/10.1007/s10393-010-0312-3

International audience In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between rat populations from the plague focus (central highlands) and those from the plague-free zone (low altitude area) was confirmed to be a widespread phenomenon. In rats from the plague focus, we observed that sex influenced plague susceptibility, with males slightly more resistant than females. Other individual factors investigated (weight and habitat of sampling) did not affect plague resistance. When infected at high bacterial dose (more than 10⁵ bacteria injected), rats from the plague focus died mainly within 3-5 days and produced specific antibodies, whereas after low-dose infection (< 5,000 bacteria), delayed mortality was observed and surviving seronegative rats were not uncommon. These results concerning plague resistance level and the course of infection in the black rat would contribute to a better understanding of plague circulation in Madagascar.