Human Leptospirosis caused by a new antigenically unique Leptospira associated with a Rattus species reservoir in the Peruvian Amazon

• Autores: Matthias, M.; Ricaldi, Jessica. N.; Cespedes, Manuel; Díaz, María Mónica; Galloway, R. L.; Saito Mayuko; Steigerwalt, Arnold G.; Patra, Kallash P.; Vidal Ore, Carlos; Gotuzzo, Eduardo; Gilman, Robert H.; Levett, Paul N.; Vinetz, Joshep M.
• Año de publicación: 2008
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: Leptospira; Peruvian Amazon; new species; Rattus
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

As part of a prospective study of leptospirosis and biodiversity of Leptospira in the Peruvian Amazon, a new Leptospira species was isolated from humans with acute febrile illness. Field trapping identified this leptospire in peridomestic rats (Rattus norvegicus, six isolates; R. rattus, two isolates) obtained in urban, peri-urban, and rural areas of the Iquitos region. Novelty of this species was proven by serological typing, 16S ribosomal RNA gene sequencing, pulsed-field gel electrophoresis, and DNA-DNA hybridization analysis. We have named this species “Leptospira licerasiae” serovar Varillal, and have determined that it is phylogenetically related to, but genetically distinct from, other intermediate Leptospira such as L. fainei and L. inadai. The type strain is serovar Varillal strain VAR 010T, which has been deposited into internationally accessible culture collections. By microscopic agglutination test, “Leptospira licerasiae” serovar Varillal was antigenically distinct from all known serogroups of Leptospira except for low level cross-reaction with rabbit anti–L. fainei serovar Hurstbridge at a titer of 1∶100. LipL32, although not detectable by PCR, was detectable in “Leptospira licerasiae” serovar Varillal by both Southern blot hybridization and Western immunoblot, although on immunoblot, the predicted protein was significantly smaller (27 kDa) than that of L. interrogans and L. kirschneri (32 kDa). Isolation was rare from humans (2/45 Leptospira isolates from 881 febrile patients sampled), but high titers of MAT antibodies against “Leptospira licerasiae” serovar Varillal were common (30%) among patients fulfilling serological criteria for acute leptospirosis in the Iquitos region, and uncommon (7%) elsewhere in Peru. This new leptospiral species reflects Amazonian biodiversity and has evolved to become an important cause of leptospirosis in the Peruvian Amazon.
Fil: Matthias, M.. University of California at San Diego; Estados Unidos
Fil: Ricaldi, Jessica. N.. University of California at San Diego; Estados Unidos
Fil: Cespedes, Manuel. National Institute of Health; Perú
Fil: Díaz, María Mónica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Programa de Investigación de Biodiversidad Argentina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina
Fil: Galloway, R. L.. Disease Control and Prevention, Atlanta; Estados Unidos
Fil: Saito Mayuko. Asociacion Benefica PRISMA; Perú
Fil: Steigerwalt, Arnold G.. Centers for Disease Control and Prevention, Atlanta; Estados Unidos
Fil: Patra, Kallash P.. University of California at San Diego; Estados Unidos
Fil: Vidal Ore, Carlos. Ministry of Health; Perú
Fil: Gotuzzo, Eduardo. Universidad Peruana Cayetano Heredia; Perú
Fil: Gilman, Robert H.. Johns Hopkins Bloomberg School of Public Health; Estados Unidos
Fil: Levett, Paul N.. Saskatchewan Disease Control Laboratory; Canadá
Fil: Vinetz, Joshep M.. University of California at San Diego; Estados Unidos