Acta Tropica 126 (2013) 164–166 Contents lists available at SciVerse ScienceDirect Acta Tropica journa l h o me pag e: www.elsevier.com/locate/actatropica Short communication Molecular characterization of virulent Leptospira interrogans serogroup Icterohaemorrhagiae isolated from Cavia aperea Leonardo G. Monte a , Sérgio Jorge b , Marina A. Xavier a , Fernanda M.A. Leal a , Marta G. Amaral a , Fabiana K. Seixas c , Odir A. Dellagostin b , Cláudia P. Hartleben a,∗ a Laboratório de Imunodiagnóstico, Núcleo de Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário Capão do Leão, CP 354, CEP: 96010-900 Pelotas, RS, Brazil b Laboratório de Vacinologia, Universidade Federal de Pelotas, Campus Universitário Capão do Leão, CP 354, CEP: 96010-900 Pelotas, RS, Brazil c Laboratório de Genômica Funcional, Universidade Federal de Pelotas, Campus Universitário Capão do Leão, CP 354, CEP: 96010-900 Pelotas, RS, Brazil a r t i c l e i n f o Article history: Received 17 October 2012 Received in revised form 31 January 2013 Accepted 11 February 2013 Available online 19 February 2013 Keywords: Leptospirosis Brazilian guinea pig Wild rodent a b s t r a c t Leptospirosis is a worldwide zoonotic infection caused by pathogenic Leptospira. Synanthropic rodents are recognized carriers of leptospires; however, the role of wild rodents in the epidemiology of the disease is still incipient. In this work, we describe Leptospira strain isolated from Cavia aperea (Brazilian guinea pig). The isolated strain was characterized by partial rpoB gene sequencing, variable-number tandem- repeats and histopathological analysis. The strain was identified as Leptospira interrogans, serogroup Icterohaemorrhagiae and caused clinical signs of leptospirosis in the hamster model, attesting to its virulence. In conclusion, these findings could be useful for elucidating the epidemiological role of C. aperea in leptospirosis. © 2013 Elsevier B.V. All rights reserved. 1. Introduction Leptospirosis is a zoonosis of global distribution caused by infec- tion with pathogenic spirochetes of the genus Leptospira (Adler and de la Pena, 2010). Leptospires can survive in the environment for several weeks and usually gain access to new hosts by passage across mucous membrane or through skin abrasions (Levett, 2001; Faine et al., 1999). In Latin America the prevalence of leptospirosis is high because of environmental conditions and distinct leptospiral reservoir species (Ko et al., 2009; Levett, 2001). The epidemiology of leptospirosis involves more than 260 pathogenic serovars and the reservoirs or maintenance hosts are difficult to identify, moreover, they can be persistently infected without clinical signs and have a low serological response (Adler and de la Pena, 2010; Monahan et al., 2009). Synanthropic rodents were the first recognized carriers of lep- tospires and the major animal species that can shed the bacteria throughout their lifespan (WHO, 2003). They have been incrimi- nated as a primary source of infection of human beings (Adler and ∗ Corresponding author. Tel.: +55 53 32757517; fax: +55 53 32757551. E-mail addresses: leonardogmonte@hotmail.com (L.G. Monte), sergiojorgevet@hotmail.com (S. Jorge), xaviermarinaa@gmail.com (M.A. Xavier), fehleal@yahoo.com.br (F.M.A. Leal), seixas.fk@gmail.com (F.K. Seixas), odir@terra.com.br (O.A. Dellagostin), clauhart@terra.com.br, hartlebenclaudia@gmail.com (C.P. Hartleben). de la Pena, 2010; Clark and Olfert, 1986). Wild rodents also have been considered potential Leptospira reservoirs; however, their role in the epidemiology of the disease is unclear (Turk et al., 2003). Among these animals, the Brazilian guinea pig (Cavia aperea), a small wild herbivore rodent, may have potential as a source of infec- tion on the cycle of leptospirosis in Latin America since C. aperea is found in Colombia, Ecuador, Venezuela, Guyana, Bolivia, north Argentina, Uruguay, Paraguay and Brazil (Redford and Eisenberg, 1992; Dunnum et al., 2008). In this work, we reported the isolation of pathogenic Leptospira from the Brazilian guinea pig in Southern Brazil. 2. Materials and methods 2.1. Isolation of leptospires A free-living Brazilian guinea pig was admitted to the Fed- eral University of Pelotas for veterinary medical care in the city of Pelotas, RS, Brazil (31 ◦ 46 ′′ S, 52 ◦ 20 ′′ W). After death of animal, the kidneys were aseptically removed and macerated under ster- ile conditions in liquid Ellinghausen–McCullough–Johnson–Harris (EMJH) medium without antibiotics, supplemented with Lep- tospira Enrichment EMJH (Difco, BD Diagnostics, Sparks, MD, USA). The kidney cultures were incubated at 30 ◦ C and exam- ined weekly by dark-field microscopy. The procedures used in the present study were approved by the federal author- ities (Instituto Brasileiro do Meio Ambiente e dos Recursos 0001-706X/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.actatropica.2013.02.009