Epidemiological relevance in the detection of Bartonella henselae in wild and synanthropic rodents in Argentina

URDAPILLETA MARA; SAVCHENKO, EKATERINA; ESPINOZA-CARNIGLIA MARIO; BURGOS F. ELIANA; GIULIANI MAGALÍ; CORTÉS MICAELA; LARESCHI MARCELA; SALOMON, OSCAR D.

La Plata

Congreso; II Congress of the Latin American Society for Vector Ecology; 2022

Latin American Society for Vector Ecology

The genus Bartonella comprises gram-negative bacteria associated with emerging diseases in animals and humans, known as bartonellosis. Cat scratch disease (CSD) is the best known bartonellosis in humans, and is caused by Bartonella henselae and Bartonella clarridgeiae. Rodents are natural reservoirs for many Bartonella species, and fleas have a key role in the transmission cycle. The prevalence of Bartonella varies according to the environments and hosts involved. Currently, in Argentina, Bartonella infection is known in rodents of the species S. aquaticus, D. kempi and Oligoryzomys flavescens. In the province of Misiones, a case of Bartonella encephalitis was reported in a young girl who lived in close contact with flea-infested cats. In turn, B. clarridgeiae was detected in the blood of domestic cats and in Ctenocephalides felis felis fleas. Due to its scarce knowledge, the aim of this study was to detect and molecularly characterize Bartonella spp. in rodents from Misiones. DNA was extracted from spleen samples of 123 rodents (55 Rattus rattus, 24 Mus musculus, 36 Akodon montensis, 5 Calomys tener, 3 Oligoryzomys nigripes) captured in environments with different degrees of anthropogenic disturbance: urban and peri-urban areas, anthropized forest environments, primary and secondary forest areas, and agricultural crops. Nested PCR was performed using Bartonella genus-specific primers that amplified a fragment of the citrate synthase enzyme gene (gltA). PCR products were sequenced and compared with sequences stored in the NIH/NCBI (National Center for Biological Information) database. Bartonella spp. were detected in: R. rattus 5/55 (9.1%) captured in urban and peri-urban areas of Puerto Iguazú, A. montensis 2/36 (5.5%) in peri-urban area and anthropized jungle environments, and C. tener 1/5 (20%) in agricultural crops in Wanda. Sequencing and phylogenetic analyses allowed the identification of 3 genotypes in rodents, corresponding to B. henselae detected in R. rattus, and for the first time worldwide in A. montesis and C. tener. The presence of B. henselae in rodents in anthropized areas has public health implications, given the close interactions between human populations, animals and their fleas, due to the potential epidemiological nexus with cat scratch disease. Our results provide the first evidence of Bartonella in wild and synanthropic rodents, evidencing the need for further studies for the development of specific monitoring measures to prevent the emergence of zoonotic diseases in interface areas of Argentina.