• Decrease font size
  • Return font size to normal
  • Increase font size
U.S. Department of Health and Human Services

Scientific Publications by FDA Staff

  • Print
  • Share
  • E-mail

Search Publications



Starting Date

Ending Date

Order by

Entry Details

J Infect Dis 2013 Apr;207(8):1328-38

A New Model of Progressive Visceral Leishmaniasis in Hamsters by Natural Transmission via Bites of Vector Sand Flies.

Aslan H, Dey R, Meneses C, Castrovinci P, Jeronimo SM, Oliva G, Fischer L, Duncan RC, Nakhasi HL, Valenzuela JG, Kamhawi S


Background.¿Visceral leishmaniasis (VL) is transmitted by sand flies. Protection of needle-challenged vaccinated mice was abrogated in vector-initiated cutaneous leishmaniasis, highlighting the importance of developing natural transmission models for VL. Methods.¿We used Lutzomyia longipalpis to transmit Leishmania infantum or Leishmania donovani to hamsters. Vector-initiated infections were monitored and compared with intracardiac infections. Body weights were recorded weekly. Organ parasite loads and parasite pick-up by flies were assessed in sick hamsters. Results.¿Vector-transmitted L. infantum and L. donovani caused ¿5-fold increase in spleen weight compared with uninfected organs and had geometric mean parasite loads (GMPL) comparable to intracardiac inoculation of 10(7)-10(8) parasites, although vector-initiated disease progression was slower and weight loss was greater. Only vector-initiated L. infantum infections caused cutaneous lesions at transmission and distal sites. Importantly, 45.6%, 50.0%, and 33.3% of sand flies feeding on ear, mouth, and testicular lesions, respectively, were parasite-positive. Successful transmission was associated with a high mean percent of metacyclics (66%-82%) rather than total GMPL (2.0 × 10(4)-8.0 × 10(4)) per midgut. Conclusions.¿This model provides an improved platform to study initial immune events at the bite site, parasite tropism, and pathogenesis and to test drugs and vaccines against naturally acquired VL.

Category: Journal Article
PubMed ID: #23288926 DOI: 10.1093/infdis/jis932
Includes FDA Authors from Scientific Area(s): Biologics
Entry Created: 2012-05-11 Entry Last Modified: 2013-04-29