title: Infectiousness of Sylvatic and Synanthropic Small Rodents Implicates a Multi-host Reservoir of Leishmania (Viannia) braziliensis.
abstract: BACKGROUND
  The possibility that a multi-host wildlife reservoir is responsible for maintaining transmission of Leishmania (Viannia) braziliensis causing human cutaneous and mucocutaneous leishmaniasis is tested by comparative analysis of infection progression and infectiousness to sandflies in rodent host species previously shown to have high natural infection prevalences in both sylvatic or/and peridomestic habitats in close proximity to humans in northeast Brazil.
  
  
  METHODS
  The clinical and parasitological outcomes, and infectiousness to sandflies, were observed in 54 colonized animals of three species (18 Necromys lasiurus, 18 Nectomys squamipes and 18 Rattus rattus) experimentally infected with high (5.5 × 10(6)/ml) or low (2.8 × 10(5)/ml) dose L. (V.) braziliensis (MBOL/BR/2000/CPqAM95) inoculum. Clinical signs of infection were monitored daily. Whole animal xenodiagnoses were performed 6 months post inoculation using Lutzomyia longipalpis originating from flies caught in Passira, Pernambuco, after this parasite evaluation was performed at necropsy. Heterogeneities in Leishmania parasite loads were measured by quantitative PCR in ear skin, liver and spleen tissues.
  
  
  RESULTS
  All three rodent species proved to establish infection characterized by short-term self-resolving skin lesions, located on ears and tail but not on footpads (one site of inoculation), and variable parasite loads detected in all three tissues with maximum burdens of 8.1 × 10(3) (skin), 2.8 × 10(3) (spleen), and 8.9 × 10(2) (liver). All three host species, 18/18 N. lasiurus, 10/18 N. squamipes and 6/18 R. rattus, also proved infectious to sandflies in cross-sectional study. R. rattus supported significantly lower tissue parasite loads compared to those in N. lasiurus and N. squamipes, and N. lasiurus appeared to be more infectious, on average, than either N. squamipes or R. rattus.
  
  
  CONCLUSIONS
  A multi-host reservoir of cutaneous leishmaniasis is indicated in this region of Brazil, though with apparent differences in the competence between the rodent species. The results provide preliminary insights into links between sylvatic and peri-domestic transmission cycles associated with overlaps in the rodent species' ecological niches.
authors.affiliation: Department of Immunology, Aggeu Magalhães Research Center-Oswaldo Cruz Foundation (FIOCRUZ), Recife, Pernambuco, Brazil; University of Pernambuco, Recife, Pernambuco, Brazil.
authors.forename: Maria S
authors.initials: MS
authors.lastname: Andrade
authors.affiliation: Warwick Infectious Disease Epidemiology Research (WIDER) and School of Life Sciences, University Warwick, Coventry, United Kingdom.
authors.forename: Orin
authors.initials: O
authors.lastname: Courtenay
authors.affiliation: Department of Immunology, Aggeu Magalhães Research Center-Oswaldo Cruz Foundation (FIOCRUZ), Recife, Pernambuco, Brazil.
authors.forename: Maria E F
authors.initials: ME
authors.lastname: Brito
authors.affiliation: Department of Immunology, Aggeu Magalhães Research Center-Oswaldo Cruz Foundation (FIOCRUZ), Recife, Pernambuco, Brazil.
authors.forename: Francisco G
authors.initials: FG
authors.lastname: Carvalho
authors.affiliation: Department of Immunology, Aggeu Magalhães Research Center-Oswaldo Cruz Foundation (FIOCRUZ), Recife, Pernambuco, Brazil.
authors.forename: Ana Waléria S
authors.initials: AW
authors.lastname: Carvalho
authors.affiliation: Department of Immunology, Aggeu Magalhães Research Center-Oswaldo Cruz Foundation (FIOCRUZ), Recife, Pernambuco, Brazil.
authors.forename: Fábia
authors.initials: F
authors.lastname: Soares
authors.affiliation: Department of Immunology, Aggeu Magalhães Research Center-Oswaldo Cruz Foundation (FIOCRUZ), Recife, Pernambuco, Brazil.
authors.forename: Silvia M
authors.initials: SM
authors.lastname: Carvalho
authors.affiliation: Department of Immunology, Aggeu Magalhães Research Center-Oswaldo Cruz Foundation (FIOCRUZ), Recife, Pernambuco, Brazil.
authors.forename: Pietra L
authors.initials: PL
authors.lastname: Costa
authors.affiliation: Biosiences Institute, São Paulo University, São Paulo, São Paulo, Brazil.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Zampieri
authors.affiliation: Biosiences Institute, São Paulo University, São Paulo, São Paulo, Brazil.
authors.forename: Lucile M
authors.initials: LM
authors.lastname: Floeter-Winter
authors.affiliation: Biomedical Institute, São Paulo University, São Paulo, São Paulo, Brazil.
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Shaw
authors.affiliation: Department of Immunology, Aggeu Magalhães Research Center-Oswaldo Cruz Foundation (FIOCRUZ), Recife, Pernambuco, Brazil.
authors.forename: Sinval P
authors.initials: SP
authors.lastname: Brandão-Filho
mesh_terms: D000818:Animals; D001938:Brazil / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004197:Disease Reservoirs; D018562:Disease Transmission, Infectious; D005260:Female; D007892:Leishmania braziliensis / Q000302:isolation & purification*; D016773:Leishmaniasis, Cutaneous / Q000469:parasitology / Q000473:pathology / Q000635:transmission / Q000662:veterinary*; D008297:Male; D059208:Parasite Load; D011576:Psychodidae / Q000469:parasitology*; D051381:Rats / Q000469:parasitology*; D012376:Rodent Diseases / Q000469:parasitology* / Q000473:pathology / Q000635:transmission; D016205:Sigmodontinae / Q000469:parasitology*